/**
 * EdenAbacus V2 Theme - Playful Sunny Edition
 * 视觉风格：奶油黄背景 + 糖果色 3D 按钮 + 绘本风粗边框
 * 目标人群：儿童与学生，强调亲和力与快乐感。
 */

/* ══════════════════════════════════════════════
   V2 DYNAMIC THEME SYSTEM
   ═══════════════════════════════════════════════ */

:root {
    /* ── COLOUR ──────────────────────────────── */
    --v2-bg-main:       #FFF9E6;   /* page background */
    --v2-surface:       #FFFFFF;   /* card surface */
    --v2-primary:       #FF8A00;   /* orange — main accent */
    --v2-primary-dark:  #E67E00;
    --v2-secondary:     #4CAF50;   /* green — success */
    --v2-secondary-dark:#388E3C;
    --v2-accent:        #2196F3;   /* blue */
    --v2-danger:        #FF5252;   /* red */
    --v2-danger-dark:   #C62828;
    --v2-text:          #4A4A4A;   /* body text */
    --v2-text-dark:     #333333;   /* strong text */
    --v2-muted:         #9A9A9A;   /* secondary / hint text */
    --v2-green:         #4CAF50;
    --v2-green-dark:    #2E7D32;
    --v2-red:           #FF5252;
    --v2-red-dark:      #C62828;

    /* ── BORDER ──────────────────────────────── */
    --v2-border-main:   #E0D0B0;
    --v2-border-width:  3px;
    --v2-card-border:   var(--v2-border-width) solid var(--v2-border-main);

    /* ── SHADOW ──────────────────────────────── */
    --v2-shadow-depth:  4px;
    --v2-shadow-soft:   0 var(--v2-shadow-depth) 0 var(--v2-border-main);
    --v2-shadow-inner:  inset 0 2px 5px rgba(0, 0, 0, 0.08);
    --v2-shadow-flat:   none;

    /* ── RADIUS ──────────────────────────────── */
    --v2-radius-card:   24px;   /* large cards */
    --v2-radius-chip:   12px;   /* chips, small cards, setting cards */
    --v2-radius-btn:    20px;   /* buttons */
    --v2-radius-icon:   20px;   /* icon containers */

    /* ── TYPOGRAPHY ──────────────────────────── */
    --v2-font-main:     'Outfit', sans-serif;
    --v2-font-num:      'Outfit', sans-serif;
    --v2-size-xs:       10px;
    --v2-size-sm:       12px;
    --v2-size-md:       14px;
    --v2-size-body:     16px;
    --v2-size-lg:       18px;
    --v2-size-xl:       20px;
    --v2-size-title:    24px;
    --v2-weight-normal: 600;
    --v2-weight-bold:   800;
    --v2-weight-heavy:  900;

    /* ── INTERACTION ─────────────────────────── */
    --v2-transition:    all 0.2s cubic-bezier(0.175, 0.885, 0.32, 1.275);
    --v2-transition-fast: all 0.1s ease;
    --v2-transition-pop:  all 0.4s cubic-bezier(0.34, 1.56, 0.64, 1);

    /* ── BUTTON ──────────────────────────────── */
    --v2-btn-height:    52px;
    --v2-btn-font-size: var(--v2-size-lg);
    --v2-btn-radius:    var(--v2-radius-btn);
    --v2-btn-shadow:    0 8px 0 var(--v2-primary-dark);

    /* ── LAYOUT ──────────────────────────────── */
    --v2-gap-screen:    20px;   /* gap between cards on screen */
    --v2-gap-card:       8px;   /* gap inside a card */
    --v2-pad-card:      20px 15px;
    --v2-pad-screen:    10px 6px;
    --v2-header-height: 90px;

    /* ── LEGACY ALIASES (keep for backwards compat) ── */
    --v2-text-main:     var(--v2-text);
    --v2-card-bg:       var(--v2-surface);
    --v2-bg:            var(--v2-bg-main);
    --v2-shadow-raised: var(--v2-shadow-soft);
    --v2-glass:         none;
}

/* 1. Playful Sunny (Default) */
.v2-theme-sunny {
    --v2-bg-main: #FFF9E6;
    --v2-primary: #FF8A00;
    --v2-border-main: #E0D0B0;
    --v2-font-num: 'Outfit', sans-serif;
}

/* 2. Modern Premium (Apple Style) */
.v2-theme-modern {
    --v2-bg-main: #F2F2F7;
    --v2-primary: #007AFF;
    --v2-secondary: #34C759;
    --v2-border-main: rgba(0,0,0,0.1);
    --v2-card-bg: rgba(255, 255, 255, 0.85);
    --v2-text-main: #1C1C1E;
    --v2-card-border: 1px solid rgba(0,0,0,0.1);
    --v2-shadow-soft: 0 10px 30px rgba(0, 0, 0, 0.08);
    --v2-glass: blur(20px);
    --v2-font-num: 'Montserrat', sans-serif; /* 现代感字体 */
}

/* 3. Space Adventure (Neon Style) */
.v2-theme-space {
    --v2-bg-main: #0B0E14;
    --v2-primary: #BB86FC;
    --v2-secondary: #03DAC6;
    --v2-border-main: #BB86FC;
    --v2-card-bg: #1E1E1E;
    --v2-text-main: #E0E0E0;
    --v2-card-border: 2px solid var(--v2-primary);
    --v2-shadow-soft: 0 0 20px rgba(187, 134, 252, 0.3);
    --v2-font-num: 'Space Mono', monospace; /* 科技感等宽字体 */
}

#app {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: var(--v2-bg-main);
    display: flex;
    flex-direction: column;
    color: var(--v2-text);
    font-family: 'Outfit', 'Montserrat', sans-serif;
    overflow: hidden;
}

/* Dot pattern background */
#app::before {
    content: '';
    position: absolute;
    inset: 0;
    background-image: radial-gradient(rgba(224, 208, 176, 0.3) 2px, transparent 2px);
    background-size: 30px 30px;
    z-index: -1;
}

/* ══════════════════════════════════════════════
   SCREEN & CONTENT
   ═══════════════════════════════════════════════ */

.v2-screen {
    display: none;
    flex: 1;
    height: 100%;
    flex-direction: column;
    overflow: hidden;
    position: relative;
    animation: v2PopIn 0.4s cubic-bezier(0.34, 1.56, 0.64, 1);
    width: 100%;
    max-width: 100%;
}

.v2-screen.active {
    display: flex;
}

@keyframes v2PopIn {
    from { opacity: 0; transform: scale(0.9); }
    to { opacity: 1; transform: scale(1); }
}

.v2-header {
    font-size: var(--v2-size-title);
    font-weight: var(--v2-weight-heavy);
    text-align: center;
    padding: 15px 10px;
    color: var(--v2-primary);
    text-shadow: 2px 2px 0 var(--v2-surface);
    position: relative;
    display: flex;
    justify-content: center;
    align-items: center;
}

.v2-header-gear {
    position: absolute;
    right: 20px;
    font-size: 20px;
    color: var(--v2-primary);
    cursor: pointer;
    transition: transform 0.3s;
    width: 40px;
    height: 40px;
    display: flex;
    align-items: center;
    justify-content: center;
    background: white;
    border-radius: 12px;
    box-shadow: 2px 2px 0 var(--v2-border-main);
}

.v2-header-gear:active {
    transform: scale(0.9) rotate(45deg);
}

.v2-content {
    flex: 1;
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 16px;
    padding: 12px 10px;
    overflow-y: auto;
    -webkit-overflow-scrolling: touch;
    width: 100%;
    box-sizing: border-box;
}

.v2-footer {
    padding: 16px 20px 24px;
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 12px;
    background: white;
    border-top: var(--v2-card-border);
    border-radius: 40px 40px 0 0;
    box-shadow: 0 -8px 24px rgba(0,0,0,0.04);
    width: 100%;
    box-sizing: border-box;
}

/* ══════════════════════════════════════════════
   UNIFIED BUTTON SYSTEM
   ═══════════════════════════════════════════════ */

/* Base button — all footer / content buttons inherit this */
.v2-footer button,
.v2-content button:not(.v2-neu-key):not(.v2-step-btn) {
    width: 95%;
    max-width: 1000px;
    height: var(--v2-btn-height);
    padding: 0 24px;
    border-radius: var(--v2-btn-radius);
    border: none;
    outline: none;
    background: var(--v2-primary);
    color: var(--v2-surface);
    font-family: var(--v2-font-main);
    font-size: var(--v2-btn-font-size);
    font-weight: var(--v2-weight-heavy);
    cursor: pointer;
    position: relative;
    box-shadow: var(--v2-btn-shadow);
    transition: var(--v2-transition-fast);
    margin: 0 auto;
    display: flex;
    align-items: center;
    justify-content: center;
}

.v2-footer button:active,
.v2-content button:not(.v2-neu-key):not(.v2-step-btn):active {
    transform: translateY(var(--v2-shadow-depth));
    box-shadow: none;
}

/* Primary action button (Start / Generate) */
.v2-start-btn {
    background: var(--v2-primary);
    color: var(--v2-surface);
    box-shadow: var(--v2-btn-shadow);
    width: 100%;
    max-width: 1000px;
}

.v2-start-btn:active {
    transform: translateY(var(--v2-shadow-depth));
    box-shadow: none;
}

.v2-start-btn.disabled {
    background: #BDC3C7 !important;
    color: #ECF0F1 !important;
    box-shadow: none !important;
    opacity: 0.6 !important;
    cursor: not-allowed !important;
    pointer-events: none !important;
}

/* Secondary button (last in footer = cancel/back) */
.v2-footer button:last-child:not(.v2-start-btn) {
    background: #F0F0F0;
    color: var(--v2-muted);
    box-shadow: 0 var(--v2-shadow-depth) 0 #D0D0D0;
}

.v2-footer button:last-child:not(.v2-start-btn):active {
    transform: translateY(var(--v2-shadow-depth));
    box-shadow: none;
}

/* Back button (neumorphic style) */
.v2-back-btn {
    background: #EDF1F5;
    color: var(--v2-text);
    box-shadow: 3px 3px 6px #d1d9e6, -3px -3px 6px var(--v2-surface);
}

.v2-back-btn:active {
    box-shadow: var(--v2-shadow-inner);
}

/* ══════════════════════════════════════════════
   PLAYFUL CARDS (MODE SELECT)
   ═══════════════════════════════════════════════ */

.v2-neu-grid {
    display: grid;
    grid-template-columns: repeat(6, 1fr);
    gap: 12px;
    width: 100%;
    max-width: 1000px; /* 提升至 1000px，兼顾视觉中心与大气感 */
    margin: 0 auto;
    box-sizing: border-box;
    padding: 5px;
}

/* 网格内的卡片应该不受 max-width 限制 */
.v2-neu-grid .v2-neu-card {
    max-width: none;
    margin: 0;
}

.v2-neu-card {
    background: white;
    border: var(--v2-card-border);
    border-radius: var(--v2-radius-card);
    padding: 20px 15px;
    text-align: center;
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    gap: 8px;
    cursor: pointer;
    box-shadow: var(--v2-shadow-soft);
    transition: var(--v2-transition);
    width: 100%;
    max-width: 1000px;
    margin: 0 auto;
    box-sizing: border-box;
}

.v2-neu-card:active {
    transform: translateY(var(--v2-shadow-depth));
    box-shadow: none;
}

.v2-neu-icon {
    font-size: 36px;
    width: 80px;
    height: 80px;
    background: var(--v2-bg-main);
    border-radius: 20px;
    display: flex;
    align-items: center;
    justify-content: center;
    margin-bottom: 5px;
    background-size: cover;
    background-position: center;
}

/* 各模式图标背景色差异化 */
.v2-neu-card:nth-child(1) .v2-neu-icon { background: #FFEBEE; color: #E91E63; }
.v2-neu-card:nth-child(2) .v2-neu-icon { background: #E3F2FD; color: #2196F3; }
.v2-neu-card:nth-child(3) .v2-neu-icon { background: #E8F5E9; color: #4CAF50; }
.v2-neu-card:nth-child(4) .v2-neu-icon { background: #FFF3E0; color: #FF9800; }

.v2-neu-title {
    font-weight: 900;
    font-size: 19px;
    color: var(--v2-text);
}

.v2-neu-desc {
    font-size: 11px;
    color: var(--v2-muted);
    font-weight: 700;
    text-align: center;
}

/* ══════════════════════════════════════════════
   SETTINGS UI (PLAYFUL LIST)
   ═══════════════════════════════════════════════ */

.v2-settings-grid {
    width: 100%;
    max-width: 1000px;
}

.v2-setting-item {
    background: white;
    border: 3px solid var(--v2-border-main);
    border-radius: 28px;
    padding: 20px;
    margin-bottom: 16px;
    box-shadow: 0 6px 0 var(--v2-border-main);
}

.v2-setting-item label {
    font-weight: 900;
    font-size: 15px;
    color: var(--v2-muted);
    display: flex;
    justify-content: space-between;
    margin-bottom: 15px;
}

/* Range Input Chunky */
input[type="range"] {
    -webkit-appearance: none;
    appearance: none;
    width: 100%;
    height: 12px;
    background: #EEE;
    border-radius: 10px;
    outline: none;
}

input[type="range"]::-webkit-slider-thumb {
    -webkit-appearance: none;
    appearance: none;
    width: 32px;
    height: 32px;
    background: white;
    border: 4px solid var(--v2-primary);
    border-radius: 50%;
    cursor: pointer;
    box-shadow: 0 4px 0 rgba(0,0,0,0.1);
}

.v2-range-value {
    background: var(--v2-primary);
    color: white;
    padding: 4px 12px;
    border-radius: 12px;
    font-weight: 900;
    font-family: 'Outfit', sans-serif;
}


/* ══════════════════════════════════════════════
   PLAYER & ENGINE (SUNNY STYLE)
   ═══════════════════════════════════════════════ */

.v2-speed-card {
    background: white;
    border: 5px solid var(--v2-primary);
    border-radius: 50px;
    padding: 50px 30px;
    text-align: center;
    box-shadow: 0 15px 0 rgba(255, 138, 0, 0.2);
    width: 90%;
    max-width: 1000px;
    position: relative;
}

.v2-speed-card::after {
    content: '⭐';
    position: absolute;
    top: -20px;
    right: -20px;
    font-size: 40px;
    transform: rotate(15deg);
}

.v2-num-display {
    font-size: 100px;
    font-weight: 900;
    font-family: var(--v2-font-num);
    color: var(--v2-text-dark);
    margin-bottom: 10px;
    text-align: center;
    width: 100%;
}

.v2-feedback-card {
    background: white;
    border: 6px solid var(--v2-primary);
    border-radius: 40px;
    padding: 30px 20px;
    text-align: center;
    width: 85%;
    max-width: 1000px;
    box-shadow: 0 12px 0 rgba(0,0,0,0.05);
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    animation: v2PopIn 0.3s cubic-bezier(0.34, 1.56, 0.64, 1);
}

.v2-feedback-icon {
    font-size: 64px;
    margin-bottom: 15px;
}

.v2-feedback-msg {
    font-size: 20px;
    font-weight: 900;
    color: var(--v2-text);
    line-height: 1.4;
}

.v2-num-pos { color: #2196F3; } /* 蓝色 */
.v2-num-neg { color: #FF5252; } /* 红色 */

/* ⚠️ REMARK: 乘除法横向显示（闪算 + 看算模式共用） — 样式由 FlashEngineV2.js 和 LookEngineV2.js 引用 */
.v2-num-multi {
    white-space: nowrap;
    letter-spacing: 1px;
    /* 调整为更平衡的比例，让 3x2/3x3 依然醒目但能装下 */
    font-size: clamp(50px, 12vw, 100px) !important;
    font-weight: 900;
    font-family: var(--v2-font-num);
    width: 100%;
    text-align: center;
    color: var(--v2-text-dark);
}

.v2-step-info {
    display: inline-block;
    padding: 8px 20px;
    background: #F5F5F5;
    border-radius: 25px;
    font-size: 14px;
    font-weight: 900;
    color: var(--v2-muted);
}

/* ══════════════════════════════════════════════
   FLASH MODE SPECIFIC
   ═══════════════════════════════════════════════ */

/* ══════════════════════════════════════════════
   FLASH MODE V2 REFINED LAYOUT
   ═══════════════════════════════════════════════ */

.v2-flash-container {
    width: 100%;
    height: 100%;
    display: flex;
    flex-direction: column;
    align-items: center;
    position: relative;
}

.v2-flash-controls {
    width: 100%;
    display: flex;
    justify-content: space-between;
    padding: 10px 0;
}

.v2-mini-btn {
    background: white !important;
    color: #666 !important;
    padding: 8px 15px !important;
    font-size: 14px !important;
    border-radius: 12px !important;
    box-shadow: 0 4px 0 #DDD !important;
    width: auto !important;
    max-width: none !important;
    margin: 0 !important;
}

.v2-mini-btn:active {
    transform: translateY(2px) !important;
    box-shadow: 0 2px 0 #DDD !important;
}

/* Mouth Progress Bar */
.v2-mouth-progress-wrap {
    width: 100%;
    height: 12px;
    background: rgba(0,0,0,0.05);
    border-radius: 6px;
    overflow: hidden;
    margin: 20px 0;
}

.v2-mouth-progress-bar {
    height: 100%;
    background: var(--v2-secondary);
    border-radius: 6px;
    transition: width 0.2s ease;
}


.v2-mouth-info {
    font-size: 18px;
    font-weight: 900;
    color: var(--v2-muted);
    background: white;
    padding: 5px 20px;
    border-radius: 20px;
    border: 2px solid var(--v2-border-main);
}

@keyframes v2PulseQuick {
    0% { transform: scale(0.8); opacity: 0.5; }
    100% { transform: scale(1); opacity: 1; }
}

/* ══════════════════════════════════════════════
   PLAYER & ENGINE (SUNNY STYLE)
   ═══════════════════════════════════════════════ */

.v2-player-stage {
    flex: 1;
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    width: 100%;
    position: relative;
    overflow: hidden;
}

.v2-flash-stage {
    display: flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;
    gap: 30px;
    width: 100%;
    height: 100%;
}

/* ⚠️ REMARK: 题目显示（闪算 + 听算模式） — 样式由 FlashEngineV2.js 和 ListenEngineV2.js 引用 */
.v2-flash-display {
    font-size: 160px;
    font-weight: 900;
    font-family: var(--v2-font-num);
    color: var(--v2-text-dark);
    animation: v2PulseQuick 0.15s ease-out;
}

.v2-input-area {
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    gap: 20px;
    width: 100%;
    height: 100%;
}

/* ══════════════════════════════════════════════
   NUMPAD V2 (PLAYFUL & RESPONSIVE)
   ═══════════════════════════════════════════════ */

.v2-input-area .v2-input-label {
    font-size: 16px;
    font-weight: 800;
    color: var(--v2-text);
    margin: 0;
    opacity: 1;
}

.v2-neu-input-box {
    width: 90%;
    max-width: 300px;
    height: 80px;
    background: var(--v2-bg);
    border: none;
    border-radius: 18px;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 48px;
    font-weight: 900;
    color: var(--v2-accent);
    box-shadow: var(--v2-shadow-inner);
    position: relative; /* 为绝对定位光标做准备 */
}

/* 确保数字展示区域可以容纳绝对定位的光标 */
#v2-input-val, #v2-answer-display {
    position: relative;
    display: inline-flex;
    align-items: center;
    justify-content: center;
}

/* 确保光标不占位，且不重叠 */
.v2-cursor { 
    display: none !important;
}

.v2-neu-numpad {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 12px;
    width: 90%;
    max-width: 300px;
    justify-items: center;
}

.v2-neu-key {
    width: 100%;
    max-width: 85px;
    aspect-ratio: 1 / 1;
    height: auto;
    min-height: 60px;
    background: var(--v2-surface);
    border: var(--v2-card-border);
    border-radius: var(--v2-radius-card);
    font-size: 26px;
    font-weight: var(--v2-weight-heavy);
    color: var(--v2-text);
    cursor: pointer;
    box-shadow: var(--v2-shadow-soft);
    transition: var(--v2-transition-fast);
    display: flex;
    align-items: center;
    justify-content: center;
}

.v2-neu-key:active {
    transform: translateY(var(--v2-shadow-depth));
    box-shadow: none;
    background: var(--v2-bg-main);
}

@keyframes v2Blink { 50% { opacity: 0; } }

/* ══════════════════════════════════════════════
   NEU-STICKER CARDS (拟物贴纸风 - 还原版)
   ═══════════════════════════════════════════════ */




.v2-neu-card .v2-neu-title {
    font-size: 18px; /* 调大标题 */
    font-weight: 900;
    color: var(--v2-text);
}

.v2-neu-card .v2-neu-desc {
    font-size: 12px;
    opacity: 0.6;
    font-weight: 600;
    margin-top: 4px;
}

/* 只有在星空主题下才把图标换成星球 */
.v2-theme-space .v2-neu-icon { color: transparent; }
.v2-theme-space .v2-icon-flash  { background-image: url('../assets/v2/flash.png'); }
.v2-theme-space .v2-icon-listen { background-image: url('../assets/v2/listen.png'); }
.v2-theme-space .v2-icon-look   { background-image: url('../assets/v2/look.png'); }
.v2-theme-space .v2-icon-speed  { background-image: url('../assets/v2/speed.png'); }

/* 其他主题下的背景色 */
.v2-theme-sunny .v2-card-flash  { background-color: #FFF9C4; border-color: #FBC02D; box-shadow: 0 8px 0 #FBC02D; }
.v2-theme-sunny .v2-card-look   { background-color: #E1F5FE; border-color: #03A9F4; box-shadow: 0 8px 0 #03A9F4; }
.v2-theme-sunny .v2-card-listen { background-color: #F3E5F5; border-color: #9C27B0; box-shadow: 0 8px 0 #9C27B0; }
.v2-theme-sunny .v2-card-speed  { background-color: #E8F5E9; border-color: #4CAF50; box-shadow: 0 8px 0 #4CAF50; }

.v2-mode-card.sticker .v2-mode-name {
    font-size: 24px;
    color: white;
    text-shadow: 0 2px 10px rgba(0,0,0,0.5);
    margin: 0;
}

.v2-mode-card.sticker .v2-mode-desc {
    font-size: 10px;
    color: rgba(255,255,255,0.8);
    font-weight: normal;
    text-shadow: 0 1px 3px rgba(0,0,0,0.5);
    margin-top: 2px;
}

/* 动效：星球缩放 */
.v2-mode-card.sticker:active {
    transform: scale(0.95) translateY(4px);
    box-shadow: 0 5px 15px rgba(0,0,0,0.1), 0 1px 0 #DDD;
}

.v2-mode-card.sticker:hover {
    filter: brightness(1.1);
}

/* 只有在星空主题下才显示星球图片 */
.v2-theme-space .v2-card-flash  { background-image: url('../assets/v2/flash.png'); }
.v2-theme-space .v2-card-listen { background-image: url('../assets/v2/listen.png'); }
.v2-theme-space .v2-card-look   { background-image: url('../assets/v2/look.png'); }
.v2-theme-space .v2-card-speed  { background-image: url('../assets/v2/speed.png'); }

/* 其他主题下的默认颜色（保持贴纸外形，但换成纯色） */
.v2-theme-sunny .v2-card-flash  { background-color: #FFF9C4; border-color: #FBC02D; }
.v2-theme-sunny .v2-card-listen { background-color: #F3E5F5; border-color: #9C27B0; }
.v2-theme-sunny .v2-card-look   { background-color: #E1F5FE; border-color: #03A9F4; }
.v2-theme-sunny .v2-card-speed  { background-color: #E8F5E9; border-color: #4CAF50; }

.v2-theme-modern .v2-card-flash  { background-color: #E0F7FA; border-color: #4DD0E1; }
.v2-theme-modern .v2-card-listen { background-color: #E8EAF6; border-color: #7986CB; }
.v2-theme-modern .v2-card-look   { background-color: #F3E5F5; border-color: #BA68C8; }
.v2-theme-modern .v2-card-speed  { background-color: #F1F8E9; border-color: #AED581; }

/* 调整：非星空主题下文字颜色改为深色 */
.v2-theme-sunny .v2-mode-name, .v2-theme-modern .v2-mode-name { color: var(--v2-text-dark); text-shadow: none; }
.v2-theme-sunny .v2-mode-desc, .v2-theme-modern .v2-mode-desc { color: var(--v2-muted); text-shadow: none; }
.v2-theme-sunny .v2-mode-content, .v2-theme-modern .v2-mode-content { background: none; backdrop-filter: none; border: none; }

#v2-screen-player .screen-header {
    padding: 0 20px;
    display: flex;
    align-items: center;
    justify-content: center;
    background: var(--v2-bg-main);
    z-index: 100;
    position: relative;
    border-bottom: 2px solid rgba(0,0,0,0.05);
    height: 90px;
}

.v2-header-side {
    flex: 1;
    display: flex;
    justify-content: flex-start;
}

.v2-global-progress {
    flex: 2;
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 8px;
    margin: 0;
}

.v2-progress-stats {
    display: flex;
    gap: 8px;
}

.progress-pill {
    background: var(--v2-primary);
    color: white;
    font-size: 11px;
    font-weight: 900;
    padding: 4px 12px;
    border-radius: 50px;
    box-shadow: 0 3px 0 rgba(0,0,0,0.1);
    white-space: nowrap;
}

.v2-progress-bar-wrap {
    width: 100%;
    max-width: 180px;
    height: 8px;
    background: rgba(0,0,0,0.1);
    border-radius: 12px;
    overflow: hidden;
    border: none;
}

.v2-progress-bar {
    height: 100%;
    background: linear-gradient(90deg, var(--v2-secondary), var(--v2-primary));
    width: 0%;
    transition: width 0.1s linear, background-color 0.2s ease;
    border-radius: 12px;
    box-shadow: 0 0 8px rgba(108, 99, 255, 0.4);
}

.v2-header-controls {
    flex: 1;
    display: flex;
    justify-content: flex-end;
    gap: 12px;
}

/* 强力锁定：确保训练界面顶部的三个按钮风格完全一致（白底、粗边、3D投影） */
#v2-screen-player .screen-header button.back-btn,
#v2-screen-player .screen-header button.pause-btn,
#v2-screen-player .screen-header button.skip-btn {
    width: 48px !important;
    height: 48px !important;
    background: white !important;
    border: 3px solid var(--v2-border-main) !important;
    border-radius: 15px !important;
    color: var(--v2-primary) !important;
    box-shadow: 0 4px 0 var(--v2-border-main) !important;
    display: flex !important;
    align-items: center !important;
    justify-content: center !important;
    font-size: 18px !important;
    cursor: pointer !important;
    transition: all 0.1s !important;
    padding: 0 !important;
    margin: 0 !important;
    outline: none !important;
}

#v2-screen-player .screen-header button:active {
    transform: translateY(2px) !important;
    box-shadow: 0 2px 0 var(--v2-border-main) !important;
}

/* ══════════════════════════════════════════════
   RESULT PAGE V2
   ═══════════════════════════════════════════════ */

.v2-result-card {
    background: white;
    border: var(--v2-card-border);
    border-radius: var(--v2-radius-card);
    padding: 30px 20px;
    width: 90%;
    max-width: 1000px;
    box-shadow: var(--v2-shadow-soft);
    text-align: center;
    margin: 0 auto;
    animation: v2PopIn 0.4s cubic-bezier(0.175, 0.885, 0.32, 1.275);
    max-height: 80vh;
    display: flex;
    flex-direction: column;
}

.v2-result-details-header {
    margin-top: 25px;
    font-size: 14px;
    font-weight: 900;
    color: var(--v2-muted);
    text-transform: uppercase;
    border-top: 2px dashed #EEE;
    padding-top: 15px;
    margin-bottom: 10px;
}

.v2-result-details-list {
    flex: 1;
    overflow-y: auto;
    padding-right: 5px;
    margin-bottom: 10px;
}

.v2-detail-item {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 12px 15px;
    background: #F9F9F9;
    border-radius: 15px;
    margin-bottom: 8px;
    border: 2px solid transparent;
}

.v2-detail-item.correct {
    background: rgba(76, 175, 80, 0.05);
    border-color: rgba(76, 175, 80, 0.1);
}

.v2-detail-item.wrong {
    background: rgba(255, 82, 82, 0.05);
    border-color: rgba(255, 82, 82, 0.1);
}

.v2-detail-item .idx {
    font-weight: 900;
    color: var(--v2-muted);
    width: 30px;
}

.v2-detail-item .detail-body {
    flex: 1;
    display: flex;
    flex-direction: column;
    align-items: flex-start;
    padding-left: 10px;
}

.v2-detail-item .q-text {
    font-size: 15px;
    font-weight: 900;
    color: #555;
    margin-bottom: 4px;
}

.v2-detail-item .ans-group {
    display: flex;
    gap: 12px;
    font-size: 13px;
    font-weight: 900;
}

.v2-detail-item .correct-ans {
    color: var(--v2-secondary);
}

.v2-detail-item .user-ans {
    color: var(--v2-danger);
    text-decoration: none; /* 移除中划线，改为文字对比更清晰 */
    opacity: 0.8;
}

/* Custom Scrollbar for details */
.v2-result-details-list::-webkit-scrollbar {
    width: 6px;
}
.v2-result-details-list::-webkit-scrollbar-thumb {
    background: #DDD;
    border-radius: 10px;
}

.v2-score-header {
    margin-bottom: 30px;
}

.v2-stars {
    font-size: 40px;
    margin-bottom: 20px;
    filter: drop-shadow(0 4px 0 rgba(0,0,0,0.1));
}

.v2-score-circle {
    width: 140px;
    height: 140px;
    background: var(--v2-bg-main);
    border: 8px solid var(--v2-secondary);
    border-radius: 50%;
    margin: 0 auto;
    display: flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;
    box-shadow: inset 0 6px 0 rgba(0,0,0,0.05);
}

.v2-score-num {
    font-size: 38px;
    font-weight: 900;
    color: var(--v2-secondary);
}

.v2-score-label {
    font-size: 14px;
    font-weight: 900;
    color: var(--v2-muted);
}

.v2-stats-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 12px;
    margin-bottom: 30px;
}

.v2-stat-item {
    background: #FDFDFD;
    padding: 15px 5px;
    border-radius: var(--v2-radius-chip);
    border: var(--v2-card-border);
    box-shadow: var(--v2-shadow-soft);
}

.v2-stat-item .label {
    display: block;
    font-size: 11px;
    color: var(--v2-muted);
    font-weight: 900;
    margin-bottom: 5px;
}

.v2-stat-item .val {
    display: block;
    font-size: 18px;
    font-weight: 900;
    color: var(--v2-text-dark);
}

.v2-result-message {
    font-size: 18px;
    font-weight: 900;
    color: var(--v2-primary);
    padding: 0 10px;
}

/* Bento Grid Layout for Homework Results */
.v2-bento-grid {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 14px;
    margin: 20px 0;
    text-align: left;
    width: 100%;
    box-sizing: border-box;
}

.v2-bento-card {
    background: #F8FAFC;
    border: 3px solid var(--v2-border-main);
    border-radius: 18px;
    padding: 14px 18px;
    box-shadow: 3px 3px 0 var(--v2-border-main);
    transition: all 0.2s ease;
    box-sizing: border-box;
}

.v2-bento-card:hover {
    transform: translateY(-2px);
    box-shadow: 5px 5px 0 var(--v2-border-main);
}

.v2-bento-card .bento-title {
    font-size: 11px;
    font-weight: 900;
    color: var(--v2-muted);
    text-transform: uppercase;
    letter-spacing: 0.5px;
}

.v2-bento-card .bento-value {
    font-size: 24px;
    font-weight: 900;
    color: var(--v2-text-dark);
    margin-top: 6px;
}

/* Ceremony header customisation */
.v2-homework-ceremony {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 10px;
    margin-bottom: 20px;
}

.v2-score-circle.active-hw {
    border-color: #6366F1;
    background: linear-gradient(135deg, #EEF2FF, white);
}

.mood-item {
    transition: all 0.2s ease;
}

.mood-item:hover {
    transform: scale(1.1);
}

#v2-teacher-sub-content {
    width: 100%;
    display: flex;
    flex-direction: column;
    align-items: stretch;
    gap: 16px;
    box-sizing: border-box;
}

/* ══════════════════════════════════════════════
   THEME SELECTOR (SKIN STORE)
   ═══════════════════════════════════════════════ */

.v2-theme-selector-wrap {
    margin-bottom: 20px;
    background: white;
    padding: 20px;
    border-radius: var(--v2-radius-card);
    border: var(--v2-card-border);
    box-shadow: var(--v2-shadow-soft);
    width: 100%;
    max-width: 1000px;
    margin-left: auto;
    margin-right: auto;
    box-sizing: border-box;
}

.v2-section-label {
    display: block;
    font-size: 14px;
    font-weight: 900;
    color: var(--v2-muted);
    margin-bottom: 15px;
    text-transform: uppercase;
    letter-spacing: 1px;
}

.v2-theme-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 15px;
}

.v2-theme-chip {
    background: white;
    border: var(--v2-card-border);
    border-radius: var(--v2-radius-chip);
    padding: 15px 10px;
    text-align: center;
    position: relative;
    cursor: pointer;
    transition: var(--v2-transition);
    box-shadow: var(--v2-shadow-soft);
}

.v2-theme-chip.active {
    border-color: var(--v2-primary);
    background: var(--v2-bg-main);
    transform: translateY(-5px);
    box-shadow: 0 8px 0 var(--v2-primary);
}

.v2-theme-chip.locked {
    opacity: 0.6;
    filter: grayscale(0.8);
    background: #F5F5F5;
}

.v2-theme-preview {
    font-size: 32px;
    margin-bottom: 8px;
}

.v2-theme-name {
    font-size: 13px;
    font-weight: 900;
    color: var(--v2-muted);
}

.v2-theme-lock {
    position: absolute;
    top: -5px;
    right: -5px;
    background: #ef4444;
    color: white;
    width: 24px;
    height: 24px;
    border-radius: 50%;
    font-size: 12px;
    display: flex;
    align-items: center;
    justify-content: center;
    border: 2px solid white;
}

/* ══════════════════════════════════════════════
   SETTINGS V2 (OPTIMIZED)
   ═══════════════════════════════════════════════ */

.v2-settings-list {
    width: 100%;
    max-width: 1000px;
    padding: 0;
    display: flex;
    flex-direction: column;
    gap: 12px;
    transition: all 0.3s ease;
    align-items: center;
    margin: 0 auto;
}

.v2-setting-card {
    background: white;
    border-radius: var(--v2-radius-card);
    padding: 20px 15px;
    border: var(--v2-card-border);
    box-shadow: var(--v2-shadow-soft);
    transition: transform 0.2s, opacity 0.2s;
    box-sizing: border-box;
    width: 100%;
    max-width: 1000px;
    margin: 0 auto;
}

.v2-card-header {
    display: flex;
    align-items: center;
    gap: 12px;
    margin-bottom: 16px;
}

.v2-card-icon {
    font-size: 20px;
    color: var(--v2-primary);
    opacity: 0.85;
    flex-shrink: 0;
}

.v2-card-label {
    font-size: 17px;
    font-weight: 900;
    color: var(--v2-text-dark);
    letter-spacing: 0.3px;
    flex: 1;
}

.v2-card-body {
    width: 100%;
    display: flex;
    flex-direction: column;
    gap: 12px;
}

/* 高级拟物步进器 (Premium Neumorphic Stepper) */
.v2-stepper {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 0;
    background: #F0F2F5;
    padding: 4px;
    border-radius: 14px;
    box-shadow: inset 0 1px 3px rgba(0,0,0,0.08);
    width: 100%;
    max-width: 240px;
    margin: 0 auto;
    box-sizing: border-box;
}

.v2-step-btn {
    width: 32px;
    height: 32px;
    border: none;
    outline: none;
    border-radius: 50%;
    background: var(--v2-primary);
    color: var(--v2-surface);
    box-shadow: none;
    display: flex;
    align-items: center;
    justify-content: center;
    cursor: pointer;
    font-size: var(--v2-size-body);
    font-weight: var(--v2-weight-heavy);
    transition: var(--v2-transition-fast);
    flex-shrink: 0;
}

.v2-step-btn:active {
    transform: scale(0.88);
    background: var(--v2-primary-dark);
}

.v2-step-value {
    flex: 1;
    text-align: center;
    font-size: var(--v2-size-lg);
    font-weight: var(--v2-weight-heavy);
    color: var(--v2-text);
    padding: 8px 12px;
    min-width: 40px;
    cursor: pointer;
    transition: var(--v2-transition-fast);
    background: transparent;
    border-radius: 14px;
    box-shadow: none;
    display: flex;
    align-items: center;
    justify-content: center;
}

.v2-step-value:hover {
    color: var(--v2-primary);
}

.v2-step-input {
    width: 100%;
    height: 100%;
    background: transparent;
    border: none;
    outline: none;
    text-align: center;
    font-size: var(--v2-size-lg);
    font-weight: var(--v2-weight-heavy);
    color: var(--v2-text);
    font-family: inherit;
    -moz-appearance: textfield !important;
    appearance: textfield !important;
    padding: 0 !important;
    margin: 0 !important;
}

.v2-step-input::-webkit-outer-spin-button,
.v2-step-input::-webkit-inner-spin-button {
    display: none !important;
    -webkit-appearance: none !important;
    margin: 0 !important;
}

/* Level Chips (自适应网格版) */
.v2-level-mini-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(75px, 1fr));
    gap: 12px;
    width: 100%;
    box-sizing: border-box;
}

.v2-level-chip {
    background: #FAFAFA;
    border-radius: 14px;
    padding: 10px 4px;
    min-height: 85px;
    text-align: center;
    border: var(--v2-card-border);
    box-shadow: var(--v2-shadow-soft);
    transition: var(--v2-transition);
    display: flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;
    box-sizing: border-box;
    overflow: hidden;
    min-width: 0;
}

.v2-level-chip.active {
    background: white;
    border-color: var(--v2-secondary);
    color: var(--v2-secondary);
    box-shadow: 0 var(--v2-shadow-depth) 0 var(--v2-secondary);
    transform: translateY(-2px);
}

.v2-level-chip:active {
    transform: scale(0.95);
    box-shadow: inset 0 2px 5px rgba(0,0,0,0.1);
}

.v2-level-chip .icon { font-size: 18px; display: block; transition: transform 0.2s; }
.v2-level-chip.active .icon { transform: scale(1.2); }
.v2-level-chip .name { font-size: 12px; font-weight: 900; }

/* Chip Group Settings (通用) */
.v2-chip-group {
    display: flex;
    flex-direction: row;
    flex-wrap: nowrap;
    gap: 6px;
    width: 100%;
    padding: 5px 0;
    box-sizing: border-box;
}

.v2-setting-chip {
    flex: 1;
    min-width: 0; /* 允许弹性压缩，彻底防止横向溢出 */
    background: #F5F5F5;
    border-radius: 12px;
    padding: 8px 2px; /* 压缩内边距，释放横向宽度 */
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 4px;
    border: var(--v2-border-width) solid #F5F5F5;
    transition: var(--v2-transition);
    cursor: pointer;
    box-sizing: border-box;
}

.v2-setting-chip.active {
    background: white;
    border-color: var(--v2-primary);
    box-shadow: 0 var(--v2-shadow-depth) 0 var(--v2-primary);
    transform: translateY(-2px);
}

.v2-setting-chip:active {
    transform: scale(0.95);
    box-shadow: inset 0 2px 5px rgba(0,0,0,0.1);
}

.v2-setting-chip .icon { 
    font-size: 18px; /* 优化图标字号，避免过于拥挤 */
    transition: transform 0.2s; 
}
.v2-setting-chip.active .icon { transform: scale(1.15); }
.v2-setting-chip .label { 
    font-size: 13px; /* 优化文字字号至 13px，在极窄屏幕上也能完美展示 */
    font-weight: 900; 
    color: var(--v2-muted); 
    transition: var(--v2-transition); 
}
.v2-setting-chip.active .label { 
    color: var(--v2-primary);
    transform: scale(1.03); /* 激活时微调放大，保证排版平滑 */
}

/* Multi-Chip Group (数字矩阵全景版 - 分行优化) */
/* 紧凑型三联排卡片 (题数、口数、位数) */
.v2-stepper-group-row {
    display: flex;
    flex-direction: column;
    gap: 8px;
    width: 100%;
}

.v2-multi-layout {
    display: flex;
    flex-direction: column;
    gap: 8px;
    width: 100%;
}

/* Stepper Group/Pair Styling (Horizontal) */
.v2-stepper-pair-horizontal {
    display: flex;
    justify-content: center;
    align-items: flex-end;
    width: 100%;
    gap: 24px;
    padding: 16px 0;
}

.v2-stepper-row {
    display: flex;
    flex-wrap: nowrap;
    justify-content: space-between;
    align-items: flex-end;
    width: 100%;
    gap: 12px;
    padding: 16px 0;
}

.v2-stepper-mini-item {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 10px;
    flex: 1;
    min-width: 0;
}

.v2-mixed-row {
    display: flex;
    flex-wrap: nowrap;
    justify-content: space-between;
    align-items: center;
    width: 100%;
    gap: 12px;
    padding: 16px 0;
}

.v2-mixed-item {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 10px;
    flex: 1;
    min-width: 0;
}

.v2-mixed-item.stepper-item {
    justify-content: center;
}

.v2-mixed-item.toggle-item {
    justify-content: center;
}

.v2-mixed-item.stepper-item .v2-stepper {
    min-width: 120px;
}

.v2-mixed-item.toggle-item .v2-toggle-inline-container {
    display: flex;
    align-items: center;
    justify-content: center;
}

.v2-stepper-mini {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 10px;
}

.v2-stepper-mini .mini-label,
.v2-stepper-mini-item .mini-label {
    font-size: 12px;
    font-weight: 900;
    color: var(--v2-muted);
    text-transform: uppercase;
    letter-spacing: 0.3px;
}

.v2-stepper-sep {
    font-size: 28px;
    font-weight: 900;
    color: var(--v2-primary);
    display: flex;
    align-items: center;
    justify-content: center;
    height: 40px;
    opacity: 0.8;
}

/* 📱 Mobile Responsive Scale down for Steppers to prevent button overlap on narrow screens */
@media (max-width: 480px) {
    .v2-setting-card {
        padding: 16px 10px;
    }
    .v2-stepper-row {
        gap: 6px;
    }
    .v2-stepper-pair-horizontal {
        gap: 12px;
    }
    .v2-mixed-row {
        gap: 8px;
    }
    .v2-stepper {
        padding: 2px;
        border-radius: 10px;
        max-width: 180px;
    }
    .v2-step-btn {
        width: 26px;
        height: 26px;
        font-size: 13px;
    }
    .v2-step-value {
        padding: 5px 6px;
        font-size: 13px;
        min-width: 32px;
        border-radius: 10px;
    }
    .v2-step-input {
        font-size: 13px;
    }
    .v2-stepper-mini {
        gap: 6px;
    }
    .v2-stepper-mini-item {
        gap: 6px;
    }
    .v2-stepper-mini .mini-label,
    .v2-stepper-mini-item .mini-label {
        font-size: 11px;
    }
    .v2-stepper-sep {
        font-size: 18px;
        height: 36px;
    }
}

/* 📱 Super Narrow Mobile viewports (e.g., screen width <= 360px) */
@media (max-width: 360px) {
    .v2-stepper-row {
        gap: 4px;
    }
    .v2-stepper {
        padding: 1px;
    }
    .v2-step-btn {
        width: 22px;
        height: 22px;
        font-size: 11px;
    }
    .v2-step-value {
        padding: 4px 4px;
        font-size: 11px;
        min-width: 26px;
    }
    .v2-step-input {
        font-size: 11px;
    }
    .v2-stepper-mini .mini-label,
    .v2-stepper-mini-item .mini-label {
        font-size: 10px;
    }
}


.v2-stepper-sample {
    width: 100%;
    text-align: center;
    font-size: 15px;
    font-weight: 900;
    color: #3498DB;
    margin-top: 12px;
    padding: 10px 12px;
    background: rgba(52, 152, 219, 0.06);
    border-radius: 12px;
    border: 1px solid rgba(52, 152, 219, 0.15);
    font-family: var(--v2-font-num);
    letter-spacing: 0.5px;
}

.v2-chip-row {
    display: flex;
    flex-wrap: wrap;
    gap: 10px;
    width: 100%;
}

.v2-chip-grid {
    display: flex;
    flex-wrap: wrap;
    gap: 10px;
    width: 100%;
}

.v2-desc-mini-title {
    font-size: 11px;
    color: var(--v2-muted);
    margin: 12px 0 8px 0;
    font-weight: 900;
    text-transform: uppercase;
    letter-spacing: 0.5px;
}

.v2-chip-row .v2-setting-chip,
.v2-chip-grid .v2-setting-chip {
    flex: 1 1 calc(25% - 10px);
    min-width: 80px;
    height: 36px;
    padding: 0 12px;
    display: flex;
    align-items: center;
    justify-content: center;
    border-radius: var(--v2-radius-chip);
    font-size: 13px;
    font-weight: 900;
    background: #F8F9FA;
    border: var(--v2-card-border);
    transition: var(--v2-transition);
    white-space: nowrap;
}

.v2-chip-row .v2-setting-chip.active {
    background: white;
    border-color: var(--v2-primary);
    color: var(--v2-primary);
    box-shadow: 0 4px 12px rgba(0,0,0,0.05);
}

/* Description Panel (新面板样式) */
.v2-desc-panel {
    margin-top: 8px;
    padding: 14px 16px;
    background: #F5F7FB;
    border-radius: 14px;
    border-left: 4px solid var(--v2-primary);
    animation: v2-fade-in-up 0.3s ease;
    width: 100%;
    box-sizing: border-box;
}

.v2-desc-title {
    font-size: 11px;
    font-weight: 900;
    color: var(--v2-primary);
    opacity: 0.75;
    margin-bottom: 6px;
    letter-spacing: 1px;
    text-transform: uppercase;
}

.v2-desc-body {
    font-size: 14px;
    font-weight: 700;
    color: #555;
    line-height: 1.5;
}

@keyframes v2-fade-in-up {
    from { opacity: 0; transform: translateY(5px); }
    to { opacity: 1; transform: translateY(0); }
}

.v2-chip-row.all-row {
    width: 100%;
}

.v2-chip-row.all-row .v2-setting-chip {
    background: #E0E0E0;
    height: 36px;
    margin-bottom: 4px;
}

.v2-chip-row .v2-setting-chip.active,
.v2-chip-grid .v2-setting-chip.plus-chip.active {
    background: white;
    border-color: var(--v2-primary);
    color: var(--v2-primary);
    box-shadow: 0 4px 0 rgba(0,0,0,0.05);
    transform: translateY(-2px);
}

.v2-chip-grid .v2-setting-chip.minus-chip.active {
    background: white;
    border-color: var(--v2-secondary);
    color: var(--v2-secondary);
    box-shadow: 0 4px 0 rgba(0,0,0,0.05);
    transform: translateY(-2px);
}

.v2-chip-grid .v2-setting-chip.minus-chip.active .label {
    color: var(--v2-secondary);
}

/* ══════════════════════════════════════════════
   LOOK & LISTEN SIMPLE STYLE (统一中心化)
   ═══════════════════════════════════════════════ */
.v2-look-simple-container, .v2-listen-stage {
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    width: 100%;
    flex: 1;
}

.v2-look-list {
    display: flex;
    flex-direction: column;
    align-items: center; /* 容器居中 */
    padding: 30px;
    min-width: 200px;
}

/* ⚠️ REMARK: 加减法竖排显示（看算模式）— 样式由 LookEngineV2.js renderQuestion() 引用 */
.v2-look-item {
    font-size: clamp(45px, 15vw, 90px);
    font-weight: 900;
    font-family: var(--v2-font-num);
    line-height: 1.1;
    display: grid;
    grid-template-columns: 0.5fr 1.5fr; /* 符号占位，数字占位 */
    align-items: center;
    width: 100%;
    font-variant-numeric: tabular-nums;
}

.v2-look-item .symbol {
    text-align: left;
    opacity: 0.8;
}

.v2-look-item .val {
    text-align: right;
}

/* ⚠️ REMARK: 加减法分割线（看算模式）— 样式由 LookEngineV2.js renderQuestion() 引用 */
.v2-look-divider {
    width: 100%;
    height: 4px;
    background: #333;
    margin: 15px 0;
    border-radius: 2px;
}


.v2-look-numpad-wrap {
    transform: scale(0.9);
    margin-top: -10px;
}

/* 迷你反馈动画 */
.v2-mini-feedback {
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    background: white;
    border: 4px solid currentColor;
    padding: 20px 40px;
    border-radius: 30px;
    text-align: center;
    z-index: 200;
    box-shadow: 0 10px 30px rgba(0,0,0,0.1);
    animation: v2MiniPop 1.2s forwards;
}

@keyframes v2MiniPop {
    0% { opacity: 0; transform: translate(-50%, -40%) scale(0.8); }
    20% { opacity: 1; transform: translate(-50%, -50%) scale(1); }
    80% { opacity: 1; transform: translate(-50%, -50%) scale(1); }
    100% { opacity: 0; transform: translate(-50%, -60%) scale(0.9); }
}

/* ══════════════════════════════════════════════
   LISTEN MODE V2 (听算)
   ═══════════════════════════════════════════════ */

.v2-listen-stage {
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    min-height: 300px;
    height: auto;
}

.v2-listen-visualizer {
    display: flex;
    align-items: center;
    gap: 8px;
    height: 60px;
    margin-bottom: 20px;
}

.v2-wave {
    width: 12px;
    height: 40px;
    background: var(--v2-primary);
    border-radius: 10px;
    animation: v2Wave 1s ease-in-out infinite;
}

.v2-wave:nth-child(2) { animation-delay: 0.2s; height: 60px; }
.v2-wave:nth-child(3) { animation-delay: 0.4s; }

@keyframes v2Wave {
    0%, 100% { transform: scaleY(0.5); opacity: 0.5; }
    50% { transform: scaleY(1.2); opacity: 1; }
}

.v2-listen-msg {
    font-size: clamp(40px, 15vw, 80px);
    font-weight: 900;
    color: var(--v2-muted);
    letter-spacing: 2px;
}

/* ══════════════════════════════════════════════
   READY SCREEN & COUNTDOWN
   ══════════════════════════════════════════════ */

.v2-ready-card {
    background: white;
    padding: 40px 30px;
    border-radius: var(--v2-radius-card);
    border: var(--v2-card-border);
    box-shadow: var(--v2-shadow-soft);
    text-align: center;
    max-width: 1000px;
    width: 90%;
    margin: 40px auto;
    animation: v2-pop-in 0.5s cubic-bezier(0.175, 0.885, 0.32, 1.275);
}

.v2-ready-icon {
    font-size: 60px;
    margin-bottom: 15px;
}

.v2-ready-title {
    font-size: 28px;
    font-weight: 900;
    color: var(--v2-primary);
    margin-bottom: 10px;
}

.v2-ready-detail {
    display: flex;
    justify-content: center;
    gap: 10px;
    flex-wrap: wrap;
    margin-bottom: 30px;
    font-size: 14px;
    color: var(--v2-muted);
}

.v2-ready-btn {
    background: var(--v2-secondary);
    color: white;
    border: none;
    padding: 18px 40px;
    border-radius: 25px;
    font-size: 20px;
    font-weight: 900;
    box-shadow: 0 8px 0 #388E3C;
    cursor: pointer;
    transition: var(--v2-transition-fast);
    width: 100%;
}

.v2-ready-btn:active {
    transform: translateY(4px);
    box-shadow: 0 4px 0 #388E3C;
}

.v2-countdown-circle {
    font-size: 120px;
    font-weight: 900;
    color: var(--v2-primary);
    text-shadow: 0 10px 0 rgba(0,0,0,0.1);
    animation: v2-pulse 0.8s infinite alternate;
    flex: 1;
    display: flex;
    align-items: center;
    justify-content: center;
    width: 100%;
}

@keyframes v2-pop-in {
    from { transform: scale(0.8); opacity: 0; }
    to { transform: scale(1); opacity: 1; }
}

@keyframes v2-pulse {
    from { transform: scale(0.9); }
    to { transform: scale(1.1); }
}

.v2-round-splash {
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    flex: 1;
    width: 100%;
}

.v2-round-splash .label {
    font-size: 20px;
    font-weight: 900;
    color: var(--v2-muted);
    letter-spacing: 4px;
    margin-bottom: 5px;
}

.v2-round-splash .num {
    font-size: 70px;
    font-weight: 900;
    color: var(--v2-primary);
    line-height: 1;
}

/* Toggle Switch */
.v2-toggle-container { display: flex; align-items: center; gap: 12px; cursor: pointer; background: #F8F9FA; padding: 8px 16px; border-radius: 20px; border: 2px solid #EEE; transition: var(--v2-transition); }
.v2-toggle-container:active { transform: scale(0.95); }
.v2-toggle-inline-container { display: flex; align-items: center; justify-content: center; cursor: pointer; transition: var(--v2-transition); }
.v2-toggle-inline-container:active { transform: scale(0.95); }
.v2-toggle { width: 44px; height: 24px; background: #DDD; border-radius: 12px; position: relative; transition: all 0.3s; }
.v2-toggle.active { background: var(--v2-secondary); }
.v2-toggle-thumb { width: 18px; height: 18px; background: white; border-radius: 50%; position: absolute; top: 3px; left: 3px; transition: all 0.3s; box-shadow: 0 2px 4px rgba(0,0,0,0.1); }
.v2-toggle.active .v2-toggle-thumb { left: 23px; }
.v2-toggle-label-text { font-size: 14px; font-weight: 900; color: var(--v2-muted); }

/* ══════════════════════════════════════════════
   V2 AUTH & PROFILE (Neumorphism & Bento)
   ═══════════════════════════════════════════════ */

/* Profile Bento Card */
.v2-profile-trigger.v2-card-profile {
    background: linear-gradient(135deg, #f5f3ff, #ede9fe) !important;
    border: var(--v2-card-border) !important;
    box-shadow: var(--v2-shadow-soft) !important;
    display: flex !important;
}

.v2-profile-trigger.v2-card-profile .v2-avatar-mini {
    background: linear-gradient(135deg, #8b5cf6, #7c3aed) !important;
    color: white !important;
}

/* Profile Trigger on Main Menu */
.v2-profile-trigger {
    grid-column: span 2;
    display: flex;
    align-items: center;
    gap: 15px;
    padding: 15px 25px;
    background: var(--v2-bg);
    box-shadow: var(--v2-shadow-flat);
    border-radius: 20px;
    cursor: pointer;
    margin-bottom: 10px;
    transition: all 0.2s ease;
}

.v2-profile-trigger:active {
    box-shadow: var(--v2-shadow-inner);
    transform: scale(0.98);
}

.v2-avatar-mini {
    width: 40px;
    height: 40px;
    background: var(--v2-surface);
    box-shadow: var(--v2-shadow-raised);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 20px;
}

#v2-username-main {
    font-weight: 800;
    font-size: 16px;
    color: var(--v2-text);
}

/* Auth Form & Inputs */
.v2-neu-form {
    padding: 10px;
}

.v2-input-label {
    display: block;
    font-size: 13px;
    font-weight: 800;
    color: var(--v2-text);
    margin-bottom: 10px;
    margin-left: 5px;
    opacity: 0.8;
}

.v2-neu-input-wrap {
    background: var(--v2-bg);
    box-shadow: var(--v2-shadow-inner);
    border-radius: 18px;
    padding: 5px 15px;
    display: flex;
    align-items: center;
}

.v2-neu-input {
    width: 100%;
    height: 50px;
    background: transparent;
    border: none;
    outline: none;
    font-family: inherit;
    font-size: 16px;
    font-weight: 700;
    color: var(--v2-text-main, var(--v2-text));
}

.v2-neu-btn-primary {
    background: var(--v2-primary);
    color: white;
    border: none;
    border-radius: 20px;
    padding: 18px;
    font-size: 16px;
    font-weight: 900;
    box-shadow: 6px 6px 12px rgba(108, 99, 255, 0.3);
    cursor: pointer;
    transition: var(--v2-transition);
}

.v2-neu-btn-primary:active {
    transform: scale(0.96);
    filter: brightness(0.9);
}

/* Loading Spinner inside Buttons */
.v2-btn-loading-spinner {
    display: inline-block;
    width: 18px;
    height: 18px;
    border: 3px solid rgba(255, 255, 255, 0.35);
    border-radius: 50%;
    border-top-color: #FFF;
    animation: v2SpinnerRotate 0.8s linear infinite;
    margin-right: 10px;
    vertical-align: middle;
}

@keyframes v2SpinnerRotate {
    to { transform: rotate(360deg); }
}

/* Profile Specific */
.v2-profile-avatar {
    width: 70px;
    height: 70px;
    background: var(--v2-surface);
    box-shadow: var(--v2-shadow-raised);
    border-radius: 25px;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 35px;
}

.v2-badge-gold {
    background: linear-gradient(135deg, #f59e0b, #d97706);
    color: white;
    font-size: 10px;
    font-weight: 900;
    padding: 3px 10px;
    border-radius: 8px;
    text-transform: uppercase;
    box-shadow: 0 4px 10px rgba(217, 119, 6, 0.3);
}

.v2-badge-silver {
    background: #E2E8F0;
    color: #475569;
    font-size: 10px;
    font-weight: 900;
    padding: 3px 10px;
    border-radius: 8px;
    text-transform: uppercase;
}

.v2-card-mini-title {
    font-size: 14px;
    font-weight: 800;
    opacity: 0.7;
    width: 100%;
    max-width: 1000px;
    margin: 0 auto;
    box-sizing: border-box;
    padding: 0 15px;
}

.v2-neu-btn-action {
    background: var(--v2-secondary);
    color: white;
    border: none;
    border-radius: 15px;
    padding: 0 20px;
    font-weight: 800;
    box-shadow: var(--v2-shadow-raised);
    cursor: pointer;
}

.v2-neu-btn-action:active {
    box-shadow: var(--v2-shadow-inner);
    transform: translateY(2px);
}

.v2-menu-item {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 18px 15px;
    border-radius: 15px;
    cursor: pointer;
    transition: var(--v2-transition);
}

.v2-menu-item:hover {
    background: rgba(0,0,0,0.03);
}

.v2-menu-item:active {
    background: rgba(0,0,0,0.06);
    transform: translateX(5px);
}

.v2-menu-item span {
    font-weight: 700;
    font-size: 15px;
}

.v2-menu-item i {
    opacity: 0.4;
    font-size: 12px;
}

/* V2 Teacher Console Specifics */
.v2-neu-select {
    background: var(--v2-bg);
    box-shadow: var(--v2-shadow-inner);
    border: none;
    border-radius: 12px;
    padding: 8px 12px;
    font-family: inherit;
    font-weight: 800;
    color: var(--v2-text);
    outline: none;
    appearance: none;
    cursor: pointer;
}

.v2-neu-btn-mini {
    background: var(--v2-bg);
    box-shadow: var(--v2-shadow-raised);
    border: none;
    border-radius: 12px;
    padding: 8px 15px;
    font-size: 12px;
    font-weight: 900;
    color: var(--v2-text);
    cursor: pointer;
    transition: var(--v2-transition);
}

.v2-neu-btn-mini:active {
    box-shadow: var(--v2-shadow-inner);
    transform: translateY(2px);
}

.v2-stat-num {
    font-family: 'Outfit', sans-serif;
    font-weight: 900;
}

/* Teacher Center Bento Card - Main Menu Version */
.v2-card-teacher {
    background: linear-gradient(135deg, #fffbeb, #fef3c7) !important;
    border: var(--v2-card-border) !important;
    box-shadow: var(--v2-shadow-soft) !important;
    transition: all 0.2s ease;
}

.v2-card-teacher:active {
    transform: translateY(var(--v2-shadow-depth));
    box-shadow: none !important;
}

.v2-card-teacher .v2-neu-icon {
    background: #fbbf24 !important;
    color: white !important;
    box-shadow: 0 4px 10px rgba(217, 119, 6, 0.2);
}

/* Profile Bento Card */
.v2-card-profile {
    background: var(--v2-bg) !important;
    border: var(--v2-card-border) !important;
    box-shadow: var(--v2-shadow-soft) !important;
    transition: all 0.2s ease;
}

.v2-card-profile:active {
    transform: translateY(var(--v2-shadow-depth));
    box-shadow: none !important;
}

.v2-card-profile .v2-avatar-mini {
    background: linear-gradient(135deg, #3b82f6, #2563eb) !important;
    box-shadow: 0 4px 10px rgba(37, 99, 235, 0.3);
}

/* V2 GRADER & SCORING STATION */
.v2-grader-dashboard {
  background: white;
  border: var(--v2-card-border);
  border-radius: var(--v2-radius-card);
  padding: 16px 20px;
  box-shadow: var(--v2-shadow-soft);
  animation: v2GraderPop 0.4s cubic-bezier(0.34, 1.56, 0.64, 1) both;
}
.v2-grader-board-card {
  width: 100%;
}
.v2-board-main {
  display: flex;
  align-items: center;
  justify-content: space-between;
}
.v2-board-score {
  font-size: 42px;
  font-weight: 900;
  color: var(--v2-primary);
  font-family: 'Outfit', sans-serif;
  display: flex;
  align-items: baseline;
  line-height: 1;
}
.v2-score-unit {
  font-size: 14px;
  font-weight: 800;
  color: var(--v2-muted);
  margin-left: 4px;
}
.v2-board-divider {
  width: 2px;
  height: 44px;
  background: var(--v2-border-main);
  margin: 0 20px;
  opacity: 0.6;
}
.v2-board-stats {
  display: flex;
  gap: 20px;
  flex: 1;
  justify-content: space-around;
}
.v2-board-stat-item {
  display: flex;
  flex-direction: column;
  align-items: center;
}
.v2-stat-label {
  font-size: 11px;
  font-weight: 900;
  color: var(--v2-muted);
  text-transform: uppercase;
  letter-spacing: 0.5px;
  margin-bottom: 4px;
}
.v2-stat-val {
  font-size: 18px;
  font-weight: 900;
  color: var(--v2-text-dark);
}

.v2-grader-grid {
  column-count: 4;
  column-gap: 12px;
  padding: 10px 0;
  width: 100%;
  box-sizing: border-box;
}
@media (max-width: 600px) {
  .v2-grader-grid {
    column-count: 3;
    column-gap: 8px;
  }
}
@media (max-width: 380px) {
  .v2-grader-grid {
    column-count: 2;
  }
}

.v2-grader-card {
  background: #FDFDFD;
  border-radius: var(--v2-radius-chip);
  padding: 8px 10px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  border: var(--v2-card-border);
  box-shadow: var(--v2-shadow-soft);
  transition: all 0.2s cubic-bezier(0.175, 0.885, 0.32, 1.275);
  cursor: pointer;
  user-select: none;
  box-sizing: border-box;
  animation: v2GraderPop 0.4s ease backwards;
  break-inside: avoid;
  margin-bottom: 10px;
}
.v2-grader-card:active {
  transform: scale(0.95);
}
.v2-grader-card.is-correct {
  background: #E8F5E9 !important;
  border-color: #4CAF50 !important;
  box-shadow: 0 4px 0 #388E3C !important;
}
.v2-grader-card.is-correct .v2-grader-val {
  color: #2E7D32 !important;
}
.v2-grader-card.is-correct .v2-grader-idx {
  background: rgba(76, 175, 80, 0.15) !important;
  color: #2E7D32 !important;
}
.v2-grader-card.is-correct .v2-grader-status-icon {
  color: #2E7D32 !important;
}

.v2-grader-card.is-wrong {
  background: #FFEBEE !important;
  border-color: #FF5252 !important;
  box-shadow: 0 4px 0 #C62828 !important;
}
.v2-grader-card.is-wrong .v2-grader-val {
  color: #C62828 !important;
  text-decoration: line-through;
}
.v2-grader-card.is-wrong .v2-grader-idx {
  background: rgba(255, 82, 82, 0.15) !important;
  color: #C62828 !important;
}
.v2-grader-card.is-wrong .v2-grader-status-icon {
  color: #C62828 !important;
}

.v2-grader-card-left {
  display: flex;
  align-items: center;
  gap: 8px;
  min-width: 0;
  flex: 1;
}
.v2-grader-idx {
  width: 20px;
  height: 20px;
  background: rgba(0,0,0,0.05);
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 10px;
  font-weight: 900;
  color: #7A8B99;
  flex-shrink: 0;
  transition: all 0.2s ease;
}
.v2-grader-val {
  font-family: 'Outfit', sans-serif;
  font-size: 16px;
  font-weight: 900;
  color: var(--v2-text-dark);
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
  transition: all 0.2s ease;
}
.v2-grader-status-icon {
  font-size: 12px;
  font-weight: 900;
  margin-left: 4px;
  flex-shrink: 0;
  transition: all 0.2s ease;
}

@keyframes v2GraderPop {
  0% { transform: scale(0.9) translateY(10px); opacity: 0; }
  100% { transform: scale(1) translateY(0); opacity: 1; }
}

@media (max-width: 600px) {
  .v2-grader-grid {
    grid-template-columns: repeat(3, 1fr);
    gap: 8px;
    padding: 6px 0;
  }
  .v2-board-score {
    font-size: 34px;
  }
  .v2-board-divider {
    margin: 0 10px;
  }
  .v2-board-stats {
    gap: 10px;
  }
  .v2-stat-val {
    font-size: 15px;
  }
}
@media (max-width: 380px) {
  .v2-grader-grid {
    grid-template-columns: repeat(2, 1fr);
  }
}

/* ══════════════════════════════════════════════
   LEGACY COMPONENTS — migrated & updated to V2 tokens
   ═══════════════════════════════════════════════ */

/* ── TOAST ──────────────────────────────────── */
#toast {
  position: fixed;
  bottom: 32px;
  left: 50%;
  transform: translateX(-50%) translateY(100px);
  background: var(--v2-bg-main);
  border: var(--v2-card-border);
  color: var(--v2-text);
  padding: 12px 20px;
  border-radius: 999px;
  font-size: var(--v2-size-sm);
  font-weight: var(--v2-weight-normal);
  z-index: 99999;
  transition: transform 0.3s cubic-bezier(0.34, 1.56, 0.64, 1);
  white-space: nowrap;
  box-shadow: var(--v2-shadow-soft);
}
#toast.show { transform: translateX(-50%) translateY(0); }

/* ── SCROLLABLE CONTENT ─────────────────────── */
.scroll-content {
  flex: 1;
  min-height: 0;
  overflow-y: auto;
  overflow-x: hidden;
  -webkit-overflow-scrolling: touch;
  display: flex;
  flex-direction: column;
}
.scroll-content::-webkit-scrollbar { width: 4px; }
.scroll-content::-webkit-scrollbar-thumb { background: var(--v2-border-main); border-radius: 2px; }

/* ── STATUS COLOURS ─────────────────────────── */
.correct       { color: var(--v2-green); }
.wrong         { color: var(--v2-red); }
.wrong-user    { background: rgba(239,68,68,0.1);  color: var(--v2-red); }
.correct-user  { background: rgba(34,197,94,0.1);  color: var(--v2-green); }

/* ── ANSWER FEEDBACK POPUP ──────────────────── */
.feedback-overlay {
  position: fixed;
  inset: 0;
  background: rgba(255,249,230,0.7);
  backdrop-filter: blur(6px);
  display: none;
  align-items: center;
  justify-content: center;
  z-index: 2000;
  opacity: 0;
  transition: opacity 0.2s;
}
.feedback-overlay.active { display: flex; opacity: 1; }

.feedback-card {
  background: var(--v2-surface);
  border: var(--v2-card-border);
  border-radius: var(--v2-radius-card);
  padding: 40px;
  width: 280px;
  max-width: 90vw;
  text-align: center;
  transform: scale(0.5);
  transition: var(--v2-transition-pop);
  box-shadow: 0 20px 0 var(--v2-border-main);
}
.feedback-overlay.active .feedback-card { transform: scale(1); }
.feedback-icon  { font-size: 80px; line-height: 1; margin-bottom: 20px; display: block; }
.feedback-text  { font-size: 32px; font-weight: var(--v2-weight-heavy); margin-bottom: 8px; }
.feedback-sub   { font-size: var(--v2-size-body); color: var(--v2-muted); font-weight: var(--v2-weight-normal); }

.feedback-card.is-correct { border-color: var(--v2-green);     box-shadow: 0 20px 0 var(--v2-green-dark); }
.feedback-card.is-correct .feedback-text { color: var(--v2-green-dark); }
.feedback-card.is-wrong   { border-color: var(--v2-red);       box-shadow: 0 20px 0 var(--v2-red-dark); }
.feedback-card.is-wrong   .feedback-text { color: var(--v2-red-dark); }

/* ── VIRTUAL ABACUS ─────────────────────────── */
.abacus-container {
  background: #fdf6e3;
  border: 8px solid #8b5e3c;
  border-radius: 20px;
  padding: 20px 30px;
  display: inline-flex;
  gap: 32px;
  box-shadow: 0 10px 0 #5d3a24, inset 0 2px 10px rgba(0,0,0,0.1);
  position: relative;
  margin-top: 20px;
  touch-action: none;
}
.abacus-reset-lever {
  position: absolute;
  top: -18px; left: 25px; right: 25px;
  height: 24px;
  background: var(--v2-primary);
  border: 2px solid var(--v2-primary-dark);
  border-radius: 12px;
  box-shadow: 0 5px 0 var(--v2-primary-dark);
  cursor: pointer;
  display: flex; align-items: center; justify-content: center;
  font-size: 11px; letter-spacing: 3px;
  font-weight: var(--v2-weight-heavy);
  color: var(--v2-surface);
  text-transform: uppercase;
  z-index: 30;
  transition: var(--v2-transition-fast);
  user-select: none;
}
.abacus-reset-lever:active { transform: translateY(3px); box-shadow: 0 2px 0 var(--v2-primary-dark); }
.abacus-reset-lever::before {
  content: '';
  position: absolute;
  left: 15px; right: 15px; top: 4px;
  height: 3px;
  background: rgba(255,255,255,0.2);
  border-radius: 2px;
}
.abacus-rod {
  width: 64px; height: 300px;
  position: relative;
  display: flex; flex-direction: column; align-items: center;
}
.abacus-rod::before {
  content: '';
  position: absolute; top: 0; bottom: 0;
  width: 4px;
  background: #d4a574;
  border-radius: 2px;
  box-shadow: inset 1px 0 2px rgba(0,0,0,0.2);
}
.abacus-divider-bar {
  position: absolute;
  top: 85px; left: -15px; right: -15px;
  height: 12px;
  background: #8b5e3c;
  z-index: 10;
  border-radius: 6px;
}
.abacus-divider-bar.has-dot::after {
  content: '';
  position: absolute;
  left: 50%; top: 50%;
  transform: translate(-50%,-50%);
  width: 6px; height: 6px;
  background: var(--v2-surface);
  border-radius: 50%;
}
.bead {
  width: 76px; height: 44px;
  border-radius: 22px;
  position: absolute;
  z-index: 5;
  transition: all 0.15s cubic-bezier(0.18, 0.89, 0.32, 1.28);
  cursor: pointer;
  pointer-events: all;
  touch-action: none;
  user-select: none;
}
.bead:active { filter: brightness(1.3); transform: scale(1.05); }
.bead-up  { background: linear-gradient(to bottom,#ffcc33,#e6b800); box-shadow: 0 4px 0 #b38f00, inset 0 2px 4px rgba(255,255,255,0.6); top: 5px; }
.bead-up.active { top: 38px; }
.bead-down { background: linear-gradient(to bottom,#a0522d,#8b4513); box-shadow: 0 4px 0 #5d2e0a, inset 0 2px 4px rgba(255,255,255,0.3); }
.bead-down-1 { bottom:145px; } .bead-down-2 { bottom:98px; }
.bead-down-3 { bottom:51px;  } .bead-down-4 { bottom:4px;  }
.bead-down-1.active { bottom:162px; } .bead-down-2.active { bottom:115px; }
.bead-down-3.active { bottom:68px;  } .bead-down-4.active { bottom:21px;  }
.abacus-label {
  position: absolute; bottom: -22px;
  font-family: var(--v2-font-main);
  font-size: var(--v2-size-sm);
  font-weight: var(--v2-weight-bold);
  color: #8b5e3c;
}
.abacus-tool-controls { padding: 24px 0; display: flex; flex-direction: column; align-items: center; gap: 16px; }

/* ── LOOK ENGINE — number display ───────────── */
.look-list {
  display: inline-flex;
  flex-direction: column;
  align-items: flex-end;
  gap: 8px;
  margin: auto;
  padding: 40px 0;
  font-variant-numeric: tabular-nums;
  min-width: 160px;
}
.look-list.dense .look-number       { font-size: 36px; }
.look-list.ultra-dense              { gap: 4px; }
.look-list.ultra-dense .look-number { font-size: 24px; }

.look-number {
  font-family: 'JetBrains Mono', var(--v2-font-num);
  font-size: 64px;
  font-weight: var(--v2-weight-heavy);
  line-height: 1.1;
  color: var(--v2-text);
  text-align: right;
  font-variant-numeric: tabular-nums;
  white-space: nowrap;
  width: 100%;
}
.look-number.negative { color: var(--v2-red-dark); }
.look-number.len-4  { font-size: 42px !important; }
.look-number.len-5  { font-size: 38px !important; }
.look-number.len-6  { font-size: 34px !important; }
.look-number.len-7  { font-size: 31px !important; }
.look-number.len-8, .look-number.len-9  { font-size: 28px !important; }
.look-number.len-10,.look-number.len-11 { font-size: 24px !important; }
.look-number.len-12,.look-number.len-13 { font-size: 20px !important; }

.look-divider-double {
  width: 100%;
  height: 80px;
  border-top: 4px solid var(--v2-text);
  border-bottom: 4px solid var(--v2-text);
  margin-top: 10px;
}
.look-mask {
  position: absolute; inset: 0;
  background: rgba(255,249,230,0.9);
  backdrop-filter: blur(8px);
  display: flex; align-items: center; justify-content: center;
  font-size: 64px;
  font-weight: var(--v2-weight-heavy);
  color: var(--v2-primary);
  opacity: 0; visibility: hidden;
  transition: all 0.3s ease;
  z-index: 10;
}
.look-mask.active { opacity: 1; visibility: visible; }

/* ── RESULT ITEMS (rendered by TrainingCore) ─── */
.result-list        { display: flex; flex-direction: column; gap: 10px; padding: 10px 0; }
.result-list-header { font-size: var(--v2-size-md); font-weight: var(--v2-weight-bold); color: var(--v2-muted); margin-bottom: 10px; padding-left: 5px; }
.result-item {
  background: var(--v2-surface);
  border-radius: var(--v2-radius-chip);
  padding: 12px 16px;
  display: flex; align-items: center; gap: 12px;
  border: var(--v2-card-border);
  box-shadow: var(--v2-shadow-soft);
}
.ri-num  { width:24px; height:24px; background:var(--v2-bg-main); border-radius:50%; display:flex; align-items:center; justify-content:center; font-size:11px; font-weight:var(--v2-weight-bold); color:var(--v2-muted); flex-shrink:0; }
.ri-expr { flex:1; font-family:var(--v2-font-num); font-size:15px; font-weight:700; color:var(--v2-text); white-space:nowrap; overflow:hidden; text-overflow:ellipsis; }
.ri-ans  { font-family:var(--v2-font-num); font-weight:var(--v2-weight-heavy); font-size:var(--v2-size-body); color:var(--v2-green-dark); }
.ri-user { font-family:var(--v2-font-num); font-weight:var(--v2-weight-heavy); font-size:var(--v2-size-body); min-width:40px; text-align:right; }
.ri-user.correct-user { color: var(--v2-green-dark); }
.ri-user.wrong-user   { color: var(--v2-red); text-decoration: line-through; opacity: 0.6; }
.ri-icon { font-size: var(--v2-size-md); flex-shrink: 0; }

/* ── WORKSHEET PRINT ────────────────────────── */
.ws-print-header { border-bottom: 2px solid black; padding-bottom: 10px; margin-bottom: 30px; display: flex; justify-content: space-between; align-items: flex-end; }
.ws-print-grid   { display: grid; grid-template-columns: repeat(10,1fr); gap: 20px 10px; }
.ws-item         { border: 1px solid #eee; padding: 10px 5px; display: flex; flex-direction: column; align-items: center; }
.ws-num-list     { font-family: var(--v2-font-main); font-size: var(--v2-size-body); text-align: right; width: 100%; margin-bottom: 10px; line-height: 1.4; }
.ws-ans-box      { width: 100%; height: 30px; border: 1px solid #000; margin-top: auto; }
.ws-idx          { font-size: var(--v2-size-xs); color: var(--v2-muted); margin-bottom: 5px; }
.ws-select {
  appearance: none;
  background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='24' height='24' viewBox='0 0 24 24' fill='none' stroke='currentColor' stroke-width='2' stroke-linecap='round' stroke-linejoin='round'%3E%3Cpolyline points='6 9 12 15 18 9'%3E%3C/polyline%3E%3C/svg%3E");
  background-repeat: no-repeat;
  background-position: right 12px center;
  background-size: 16px;
}

/* ── DEBUG TOOL ─────────────────────────────── */
.debug-question-card { background: var(--v2-surface); border-radius: var(--v2-radius-chip); padding: 16px; margin-bottom: 20px; box-shadow: var(--v2-shadow-soft); border: var(--v2-card-border); }
.debug-item { transition: var(--v2-transition); }
.debug-item:hover { transform: translateY(-2px); }
#debug-results-list { padding-bottom: 40px; }
#persistent-debug-btn { animation: debug-pulse 2s infinite; transition: var(--v2-transition-fast); }
#persistent-debug-btn:active { transform: scale(0.9); }
@keyframes debug-pulse {
  0%   { box-shadow: 0 0 0 0   rgba(245,158,11,0.7); }
  70%  { box-shadow: 0 0 0 15px rgba(245,158,11,0);   }
  100% { box-shadow: 0 0 0 0   rgba(245,158,11,0);   }
}

/* ── PRINT MEDIA ────────────────────────────── */
@media print {
  body { background: white !important; padding: 0 !important; margin: 0 !important; }
  .no-print, .bg-orb, .v2-header, .v2-footer { display: none !important; }
  #app { overflow: visible !important; min-height: auto !important; }
  .v2-screen { display: none !important; }
  #screen-worksheet-print { display: block !important; }
}

/* ── KEYFRAMES ANIMATIONS ─────────────────────── */
@keyframes popUp {
  from { transform: scale(0.8); opacity: 0; }
  to { transform: scale(1); opacity: 1; }
}

/* ══════════════════════════════════════════════
   QR SCANNER VIEWPORT (V2 Premium Style)
   ═══════════════════════════════════════════════ */
.v2-scanner-overlay {
    position: absolute;
    inset: 0;
    display: flex;
    flex-direction: column;
    justify-content: space-between;
    align-items: center;
    background: rgba(0, 0, 0, 0.45);
    z-index: 10;
    box-sizing: border-box;
    padding: 40px 20px;
}

.v2-scanner-header {
    width: 100%;
    display: flex;
    align-items: center;
    gap: 15px;
    z-index: 20;
    padding: 10px;
}

.v2-scanner-header .v2-round-btn {
    width: 44px;
    height: 44px;
    border-radius: 50%;
    background: rgba(255, 255, 255, 0.2);
    border: 1.5px solid rgba(255, 255, 255, 0.3);
    color: white;
    display: flex;
    align-items: center;
    justify-content: center;
    cursor: pointer;
    backdrop-filter: blur(8px);
    -webkit-backdrop-filter: blur(8px);
    transition: var(--v2-transition-fast);
}

.v2-scanner-header .v2-round-btn:active {
    transform: scale(0.9);
    background: rgba(255, 255, 255, 0.3);
}

.v2-scanner-title {
    font-size: 20px;
    font-weight: 900;
    color: white;
    text-shadow: 0 2px 4px rgba(0,0,0,0.3);
}

.v2-scanner-frame-wrap {
    width: 280px;
    height: 280px;
    position: relative;
    border-radius: 28px;
    overflow: hidden;
    box-shadow: 0 0 0 4000px rgba(0, 0, 0, 0.6); /* Viewport mask */
    border: 2px solid rgba(255, 255, 255, 0.25);
    z-index: 15;
}

/* Viewfinder Corners */
.v2-scanner-corners {
    position: absolute;
    inset: 10px;
    pointer-events: none;
    z-index: 18;
    background: 
        linear-gradient(to right, var(--v2-primary) 4px, transparent 4px) 0 0,
        linear-gradient(to bottom, var(--v2-primary) 4px, transparent 4px) 0 0,
        linear-gradient(to left, var(--v2-primary) 4px, transparent 4px) 100% 0,
        linear-gradient(to bottom, var(--v2-primary) 4px, transparent 4px) 100% 0,
        linear-gradient(to right, var(--v2-primary) 4px, transparent 4px) 0 100%,
        linear-gradient(to top, var(--v2-primary) 4px, transparent 4px) 0 100%,
        linear-gradient(to left, var(--v2-primary) 4px, transparent 4px) 100% 100%,
        linear-gradient(to top, var(--v2-primary) 4px, transparent 4px) 100% 100%;
    background-size: 20px 20px;
    background-repeat: no-repeat;
}

/* Laser scanning horizontal line animation */
.v2-scanner-corners::after {
    content: '';
    position: absolute;
    left: 0;
    width: 100%;
    height: 4px;
    background: linear-gradient(90deg, transparent, var(--v2-primary), transparent);
    box-shadow: 0 0 12px var(--v2-primary), 0 0 4px var(--v2-primary);
    z-index: 17;
    animation: v2ScannerLaser 2.2s cubic-bezier(0.4, 0, 0.2, 1) infinite;
    pointer-events: none;
}

@keyframes v2ScannerLaser {
    0% { top: 0%; opacity: 0; }
    5% { opacity: 1; }
    95% { opacity: 1; }
    100% { top: 100%; opacity: 0; }
}

.v2-scanner-footer {
    width: 100%;
    display: flex;
    justify-content: center;
    z-index: 20;
    padding: 10px;
}

.v2-scanner-hint {
    background: rgba(0, 0, 0, 0.65);
    color: #FFF;
    padding: 10px 20px;
    border-radius: 999px;
    font-size: 13px;
    font-weight: 800;
    letter-spacing: 0.5px;
    backdrop-filter: blur(8px);
    -webkit-backdrop-filter: blur(8px);
    border: 1px solid rgba(255, 255, 255, 0.15);
    text-align: center;
    box-shadow: 0 4px 12px rgba(0,0,0,0.25);
    animation: v2ScannerPulse 1.5s ease-in-out infinite alternate;
}

@keyframes v2ScannerPulse {
    from { transform: scale(1); border-color: rgba(255, 255, 255, 0.15); }
    to { transform: scale(1.02); border-color: var(--v2-primary); }
}