/* =============================================
   CSS Variables & Themes
   ============================================= */
:root {
    --primary: #4F46E5;
    --primary-hover: #4338CA;
    --bg-color: #F3F4F6;
    --card-bg: #FFFFFF;
    --text-main: #111827;
    --text-muted: #6B7280;
    --border-color: #E5E7EB;
    --success: #10B981;
    --danger: #EF4444;
    --warning: #F59E0B;
    --hover-bg: rgba(0,0,0,0.04);
    --body-bg: var(--bg-color);

    /* spacing tokens */
    --stat-box-padding: 8px;
    --stat-grid-mb: 10px;
    --setup-panel-padding: 10px;
    --setup-panel-mb: 10px;
    --form-input-padding: 8px;
    --form-input-fs: 0.85rem;
    --form-group-mb: 8px;
    --title-mb: 10px;

    /* quiz tokens */
    --q-question-mb: 15px;
    --q-option-padding: 14px;
    --q-option-mb: 10px;
    --q-result-padding: 8px;
    --q-result-mb: 10px;
    --q-btn-gap: 10px;
    --q-btn-sec-padding: 11px 5px;
    --q-btn-pri-padding: 12px;
}

.eye-care {
    --primary: #388E3C; --primary-hover: #2E7D32;
    --bg-color: #C7EDCC; --card-bg: #E8F5E9;
    --text-main: #1B3320; --text-muted: #546E5A;
    --border-color: #A5D6A7; --success: #2E7D32;
}
/* 强力覆盖用户在设置中选择的 bgColor 等自定义属性，确保护眼模式绝无刺眼白底 */
body.eye-care { background-color: var(--bg-color); }
body.eye-care .card { background-color: var(--card-bg); }
body.eye-care .question-text { color: var(--text-main); }

/* =============================================
   Reset & Base
   ============================================= */
*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; -webkit-tap-highlight-color: transparent; }

img, table { max-width: 100%; height: auto; }
table { display: block; overflow-x: auto; word-break: normal; }

body {
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
    background-color: var(--bg-color);
    color: var(--text-main);
    line-height: 1.6;
    min-height: 100vh;
    min-height: 100dvh;
    overscroll-behavior-y: none;
    display: flex;
    flex-direction: column;
}

/* 0ms 极致交互锁定：处于 loading 准备期或加载中时，拦截全页一切点击与交互，防连击 */
body.loading-pending {
    pointer-events: none;
}

.container {
    max-width: 600px;
    margin: 0 auto;
    padding: 10px;
    width: 100%;
    flex: 1;
    display: flex;
    flex-direction: column;
}

/* =============================================
   View System
   ============================================= */
.view-section { display: none; flex: 1; flex-direction: column; }
.view-section.active { display: flex; }

/* =============================================
   Card
   ============================================= */
.card {
    background-color: var(--q-bg-color, var(--card-bg));
    border-radius: 12px;
    padding: 20px;
    box-shadow: 0 4px 6px -1px rgba(0,0,0,0.1), 0 2px 4px -1px rgba(0,0,0,0.06);
    margin-bottom: 20px;
}

h1 { font-size: 1.5rem; text-align: center; margin-bottom: var(--title-mb); color: var(--primary); }
h2 { font-size: 1.2rem; text-align: center; margin-bottom: 15px; color: var(--text-main); }

/* =============================================
   Stats Grid
   ============================================= */
.stats-grid {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 12px;
    margin-bottom: var(--stat-grid-mb);
}
#dashboard-title {
    margin-top: 12px;
    margin-bottom: 15px;
}
.stat-box {
    background: var(--card-bg);
    border: 1px solid var(--border-color);
    padding: var(--stat-box-padding);
    border-radius: 8px;
    text-align: center;
    display: flex;
    flex-direction: column;
    justify-content: center;
    height: 100%;
    box-sizing: border-box;
}
.stat-box .value { font-size: 1.5rem; font-weight: bold; color: var(--primary); line-height: 1.2; }
.stat-box .label { font-size: 0.875rem; color: var(--text-muted); }
.stat-box .prog  { font-size: 0.72rem; color: var(--success); line-height: 1.4; margin-top: 2px; }
.stat-box .prev  { font-size: 0.72rem; color: var(--primary);  line-height: 1.4; }

/* =============================================
   Setup Panel
   ============================================= */
.setup-panel {
    background-color: var(--card-bg);
    border: 1px solid var(--border-color);
    padding: var(--setup-panel-padding);
    border-radius: 8px;
    margin-bottom: var(--setup-panel-mb);
    border: 1px solid var(--border-color);
}
.setup-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 8px;
    margin-bottom: 8px;
}
.form-group {
    display: flex;
    align-items: center;
    gap: 5px;
    margin-bottom: var(--form-group-mb);
}
.form-group label { font-weight: bold; min-width: 42px; font-size: 0.85rem; color: var(--text-main); }
.setup-grid .form-group { margin-bottom: 0; }
.form-control {
    flex: 1; min-width: 0; width: 100%;
    padding: var(--form-input-padding);
    border: 1px solid var(--border-color);
    border-radius: 6px;
    font-size: var(--form-input-fs);
    outline: none;
    background: var(--card-bg);
    color: var(--text-main);
}
/* =============================================
   自定义下拉组件（替代原生 select，彻底控制字体和护眼主题）
   ============================================= */
.custom-select {
    flex: 1; min-width: 0;
    position: relative;
    user-select: none; -webkit-user-select: none;
}
.cs-trigger {
    display: flex; align-items: center; justify-content: space-between;
    padding: var(--form-input-padding);
    padding-right: 10px;
    border: 1px solid var(--border-color);
    border-radius: 6px;
    font-size: var(--form-input-fs);
    background: var(--card-bg);
    color: var(--text-main);
    cursor: pointer;
    transition: border-color 0.18s;
    min-height: 36px;
}
.cs-trigger:active { border-color: var(--primary); }
.custom-select.open .cs-trigger { border-color: var(--primary); border-radius: 6px 6px 0 0; }
.cs-value { flex: 1; font-size: 0.82rem; line-height: 1.3; }
.cs-arrow  { font-size: 0.7rem; color: var(--text-muted); margin-left: 4px; transition: transform 0.2s; }
.custom-select.open .cs-arrow { transform: rotate(180deg); }

.cs-dropdown {
    display: none;
    position: absolute; top: 100%; left: 0; right: 0;
    background: var(--card-bg);
    border: 1px solid var(--primary);
    border-top: none;
    border-radius: 0 0 8px 8px;
    list-style: none;
    z-index: 200;
    box-shadow: 0 6px 16px rgba(0,0,0,0.12);
    max-height: 220px; overflow-y: auto;
    animation: cs-slide-down 0.15s ease-out;
}
@keyframes cs-slide-down {
    from { opacity: 0; transform: translateY(-4px); }
    to   { opacity: 1; transform: translateY(0); }
}
.custom-select.open .cs-dropdown { display: block; }

.cs-option {
    padding: 10px 12px;
    font-size: 0.82rem;
    color: var(--text-main);
    cursor: pointer;
    border-bottom: 1px solid var(--border-color);
    transition: background 0.15s;
}
.cs-option:last-child { border-bottom: none; }
.cs-option:active,
.cs-option:hover { background: var(--bg-color); }
.cs-option.cs-selected {
    color: var(--primary);
    font-weight: 700;
    background: rgba(79,70,229,0.06);
}
/* 护眼模式 */
body.eye-care .cs-option.cs-selected {
    color: var(--primary);
    background: rgba(56,142,60,0.08);
}

.setup-hint { font-size: 0.7rem; color: var(--text-muted); margin-bottom: 8px; margin-top: -2px; }

/* =============================================
   Buttons
   ============================================= */
.btn {
    display: block; width: 100%; padding: 13px;
    border: none; border-radius: 8px;
    font-size: 0.95rem; font-weight: 600;
    cursor: pointer; text-align: center;
    margin-bottom: 12px; transition: opacity 0.2s;
    color: white;
}
.btn:active  { opacity: 0.8; }
.btn:disabled { opacity: 0.45; cursor: not-allowed; }

.btn-primary  { background-color: var(--primary); }
.btn-success  { background-color: var(--success); }
.btn-danger   { background-color: var(--danger); }
.btn-warning  { background-color: var(--warning); color: #fff; }
.btn-outline  { background-color: transparent; border: 2px solid var(--primary); color: var(--primary); }

.btn-row { display: flex; justify-content: center; gap: 16px; }
.btn-row-special {
    display: flex;
    justify-content: center;
    gap: 12px;
    max-width: 320px; /* 宽度稍微窄一点 */
    margin: 0 auto 16px; /* 水平居中，底部外边距 16px */
    width: 100%;
}
.btn-row-special .btn-action {
    flex: 1; /* 撑满剩余空间，两侧自动对齐 */
    width: auto;
    max-width: 150px;
    height: 42px;
    padding: 0; font-size: 0.88rem; margin-bottom: 0;
    display: flex; align-items: center; justify-content: center;
}
.btn-action {
    flex: 0 0 auto; width: 120px; height: 42px;
    padding: 0; font-size: 0.88rem; margin-bottom: 0;
    display: flex; align-items: center; justify-content: center;
}
@media (max-width: 440px) {
    .btn-action {
        flex: 1 1 0%;
        min-width: 0;
        width: auto;
        font-size: 0.8rem;
        padding: 0 4px;
    }
    .btn-row { gap: 8px; }
}
@media (max-width: 340px) {
    .btn-action { font-size: 0.72rem; }
}

/* 护眼按钮 */
#btn-eyecare {
    background-color: transparent;
    border: 1px solid var(--border-color);
    color: var(--text-main);
    padding: 4px 10px; border-radius: 20px;
    font-weight: normal; cursor: pointer;
    transition: all 0.3s ease; font-size: 0.85rem;
    user-select: none; -webkit-user-select: none;
}
#btn-eyecare:active { transform: scale(0.92); }
body.eye-care #btn-eyecare { background-color: rgba(227,242,228,0.85); }

/* =============================================
   微信口令快捷入口
   ============================================= */
.wx-code-box {
    background: linear-gradient(135deg, rgba(16,185,129,0.07) 0%, rgba(16,185,129,0.03) 100%);
    border: 1.5px solid var(--success);
    border-radius: 10px;
    padding: 14px;
    margin-bottom: 16px;
}
.wx-code-title {
    font-size: 1rem; font-weight: 700;
    color: var(--success); margin-bottom: 4px;
}
.wx-code-hint {
    font-size: 0.78rem; color: var(--text-muted);
    margin-bottom: 10px; line-height: 1.4;
}
.wx-code-input {
    font-size: 1.2rem; font-weight: 700;
    letter-spacing: 0.2em; text-align: center;
    border-color: var(--success);
}
.wx-code-btn {
    flex-shrink: 0; width: 80px; margin-bottom: 0;
    padding: 9px 0; font-size: 0.9rem;
}

/* 分割线 */
.login-divider {
    display: flex; align-items: center;
    margin: 14px 0; color: var(--text-muted); font-size: 0.8rem;
}
.login-divider::before,
.login-divider::after {
    content: ''; flex: 1;
    border-top: 1px solid var(--border-color);
}
.login-divider span { padding: 0 10px; white-space: nowrap; }

/* =============================================
   Bank List (login view)
   ============================================= */
.bank-list { display: flex; flex-direction: column; gap: 10px; }
.bank-item {
    padding: 14px; border: 1px solid var(--border-color);
    border-radius: 8px; cursor: pointer;
    transition: background 0.2s;
    display: flex; justify-content: space-between; align-items: center;
}
.bank-item:hover { background: var(--bg-color); }
.bank-title { font-weight: bold; font-size: 1.05rem; }
.bank-meta  { font-size: 0.8rem; color: var(--text-muted); margin-top: 4px; }
.bank-badge { padding: 2px 6px; border-radius: 4px; font-size: 0.7rem; color: white; margin-left: 4px; }
.badge-public   { background: var(--success); }
.badge-private  { background: var(--warning); }
.badge-pending  { background: var(--warning); }
.badge-rejected { background: var(--danger); }

/* Admin filter bar */
.btn-filter {
    padding: 5px 12px; border-radius: 20px;
    border: 1px solid var(--border-color);
    background: var(--card-bg); color: var(--text-muted);
    cursor: pointer; font-size: 0.82rem; transition: all 0.2s;
}
.btn-filter.active { background: var(--primary); color: #fff; border-color: var(--primary); }
#admin-filter-bar { display: none; flex-wrap: wrap; gap: 8px; margin-bottom: 12px; }
#admin-filter-bar.visible { display: flex; }

/* Review action buttons */
.review-actions { display: flex; gap: 6px; margin-top: 8px; flex-wrap: wrap; }
.btn-review {
    padding: 4px 10px; border-radius: 6px; border: none;
    cursor: pointer; font-size: 0.78rem; font-weight: 600;
    transition: opacity 0.2s;
}
.btn-review:active { opacity: 0.7; }
.btn-approve { background: var(--success); color: #fff; }
.btn-reject  { background: var(--danger);  color: #fff; }
.btn-delete  { background: var(--text-muted); color: #fff; }
.btn-rename  { background: var(--primary); color: #fff; }

/* =============================================
   Quiz View
   ============================================= */
.quiz-header {
    display: flex; justify-content: space-between;
    align-items: center; margin-bottom: 16px;
    font-size: 0.88rem; color: var(--text-muted);
}
.tag {
    background: var(--primary); color: white;
    padding: 3px 8px; border-radius: 4px;
    font-size: 0.78rem; font-weight: bold;
}
.tag-mistakes  { background: var(--danger); }
.tag-favorites { background: var(--warning); }

.question-text {
    font-size: var(--q-font-size, 1.15rem);
    color: var(--q-text-color, var(--text-main));
    font-weight: 600;
    margin-bottom: var(--q-question-mb);
    line-height: 1.55; word-break: break-all;
}
.options-list { list-style: none; margin-bottom: 0; }
.option-item {
    display: flex; align-items: flex-start;
    font-size: calc(var(--q-font-size, 1.15rem) * 0.9);
    color: var(--q-text-color, var(--text-main));
    padding: var(--q-option-padding);
    border: 2px solid var(--border-color);
    border-radius: 8px; margin-bottom: var(--q-option-mb);
    cursor: pointer; transition: all 0.18s; word-break: break-all;
}
.option-item:active  { background-color: var(--bg-color); }
.option-item.selected { border-color: var(--primary); background-color: rgba(79,70,229,0.05); }
.option-item.correct  { border-color: var(--success); background-color: rgba(16,185,129,0.1); }
.option-item.wrong    { border-color: var(--danger);  background-color: rgba(239,68,68,0.1); }
.option-prefix { font-weight: bold; margin-right: 10px; min-width: 22px; }

/* 判断题专用：A正确/B错误 横排大按钮 */
.judge-option {
    font-size: 1.05rem; font-weight: 700;
    justify-content: center;
    border-width: 2px;
    transition: all 0.18s;
}
.judge-option.judge-selected {
    border-color: var(--primary);
    background-color: rgba(79,70,229,0.08);
    box-shadow: 0 0 0 2px rgba(79,70,229,0.18);
}
.judge-option.correct.judge-selected {
    border-color: var(--success);
    background-color: rgba(16,185,129,0.12);
    box-shadow: 0 0 0 2px rgba(16,185,129,0.22);
}
.judge-option.wrong.judge-selected {
    border-color: var(--danger);
    background-color: rgba(239,68,68,0.08);
    box-shadow: 0 0 0 2px rgba(239,68,68,0.18);
}

#result-area {
    display: none;
    padding: var(--q-result-padding);
    border-radius: 8px;
    /* 与最后一个选项的间距加倍，与操作栏间距减半 */
    margin-top: calc(var(--q-option-mb) * 2);
    margin-bottom: calc(var(--q-result-mb) / 2);
    font-weight: bold; text-align: center;
}
.result-correct { background-color: rgba(16,185,129,0.1); color: var(--success); }
.result-wrong   { background-color: rgba(239,68,68,0.1);  color: var(--danger); }

/* 解析展示区 */
#explanation-area {
    display: none;
    margin: 0 0 8px 0;
    padding: 10px 14px;
    border-radius: 10px;
    border-left: 4px solid var(--warning);
    background: linear-gradient(135deg, rgba(245,158,11,0.1) 0%, rgba(245,158,11,0.04) 100%);
    font-size: 0.88rem;
    line-height: 1.6;
    color: var(--text-main);
    word-break: break-word;
    box-shadow: 0 2px 8px rgba(245,158,11,0.12);
    opacity: 1;
}
/* 动画单独通过 class 触发，避免与 display:none 冲突 */
#explanation-area.expl-show {
    animation: expl-slide-in 0.28s ease-out forwards;
}
@keyframes expl-slide-in {
    from { opacity: 0; transform: translateY(-6px); }
    to   { opacity: 1; transform: translateY(0); }
}
#explanation-area .expl-header {
    display: flex;
    align-items: center;
    gap: 6px;
    margin-bottom: 6px;
}
#explanation-area .expl-label {
    display: inline-block;
    font-size: 0.72rem;
    font-weight: 700;
    color: #fff;
    background: var(--warning);
    padding: 2px 9px;
    border-radius: 20px;
    letter-spacing: 0.04em;
    flex-shrink: 0;
}
#explanation-area .expl-content {
    font-size: 0.88rem;
    color: var(--text-main);
    line-height: 1.65;
}
/* 护眼模式下解析框色调和谐 */
body.eye-care #explanation-area {
    border-left-color: var(--primary);
    background: linear-gradient(135deg, rgba(56,142,60,0.1) 0%, rgba(56,142,60,0.03) 100%);
    box-shadow: 0 2px 8px rgba(56,142,60,0.12);
}
body.eye-care #explanation-area .expl-label {
    background: var(--primary);
}

/* Action bar (sticky bottom in quiz) */
.action-bars {
    position: sticky; bottom: 0;
    background: var(--card-bg); padding-top: 8px; z-index: 10;
    display: flex; flex-direction: column; gap: 8px;
    margin-top: 5px;
    border-top: 1px solid transparent;
    transition: border-color 0.2s;
}
.action-bars.has-explanation {
    border-top-color: rgba(245,158,11,0.2);
}
body.eye-care .action-bars.has-explanation {
    border-top-color: rgba(56,142,60,0.2);
}

/* 副操作行：移除 / 收藏 / 答案 */
.quiz-sec-row {
    display: flex; gap: 8px;
}
.quiz-sec-btn {
    flex: 1; margin-bottom: 0;
    padding: 11px 6px; font-size: 0.85rem;
}

/* 主操作行：[← 上一题] [提交答案] [下一题 →]
   三按钮全部 flex:1 = 等宽；padding 统一 = 等高
   预习模式只有两个导航按钮，各占 50%，高度与副行按钮相同 */
.quiz-main-row {
    display: flex; gap: 8px; align-items: stretch;
}
.quiz-nav-btn,
.quiz-submit-btn {
    flex: 1; margin-bottom: 0;
    padding: 11px 6px; font-size: 0.9rem;
}
.quiz-nav-btn {
    color: var(--text-muted); border-color: var(--border-color);
}

/* 手机端滑动提示 */
.swipe-hint {
    text-align: center; font-size: 0.75rem;
    color: var(--text-muted); margin: 0; padding-bottom: 2px;
    letter-spacing: 0.02em;
}

/* ── 设备自适应 ──────────────────────────────── */

/* 触控设备（手机/平板）：隐藏导航按钮，显示滑动提示 */
@media (pointer: coarse) {
    .quiz-nav-btn { display: none; }
    .exam-mode .quiz-nav-btn { display: block; }
    .swipe-hint   { display: block; }

    /* 答题卡填满可用高度，内容过长时卡片内滚动 */
    #quiz-card {
        flex: 1;
        overflow-y: auto;
        margin-bottom: 0;
    }
    /* 操作栏自动推到底部：内容短时贴屏幕底，内容长时随滚动保持可见 */
    .action-bars {
        margin-top: auto;
        position: sticky;
        bottom: 0;
    }
}

/* 鼠标设备（桌面）：显示导航按钮，隐藏提示文字 */
@media (pointer: fine) {
    .quiz-nav-btn { display: block; }
    .swipe-hint   { display: none; }
}

.back-link {
    text-align: center; display: block;
    margin-top: 6px; color: var(--text-muted);
    text-decoration: none; font-size: 0.82rem;
}
.back-link:active { color: var(--primary); }

/* Quiz content wrapper — animated */
#quiz-content { will-change: transform, opacity; }

/* =============================================
   Loading overlay
   ============================================= */
#loading {
    position: fixed; top: 0; left: 0; width: 100%; height: 100%;
    background: rgba(255,255,255,0.85); display: none;
    justify-content: center; align-items: center; z-index: 999;
    font-size: 1.1rem; font-weight: bold; color: var(--primary);
}

/* =============================================
   Mobile Specific Adjustments (< 600px)
   ============================================= */
@media (max-width: 599px) {
    /* --- 预习模式 --- */
    body[data-mode="preview"] .quiz-sec-row {
        display: flex;
        justify-content: center;
        gap: 16px;
        margin-top: 48px; /* 下移一个按钮的高度 */
        margin-bottom: 0px; /* 彻底移除下边距，防止导致底部区域产生空隙或遮挡 */
    }
    body[data-mode="preview"] .quiz-main-row {
        display: none; /* 彻底隐藏空闲的第二排，消灭父容器自带的 8px flex gap */
    }
    body[data-mode="preview"] #btn-mark,
    body[data-mode="preview"] #btn-correction {
        display: inline-flex;
        flex: 0 0 130px; /* 强制按钮宽度撑开，相较默认显著增加 */
        width: 130px;
        justify-content: center;
    }
    body[data-mode="preview"] .swipe-hint {
        margin-top: -12px; /* 深度负外边距，实现极限上提 */
        position: relative;
        z-index: 20; /* 提升渲染层级，确保文字不论怎么上移都不会被上方可能存在的背景遮挡 */
    }
    body[data-mode="preview"] .back-link {
        position: relative;
        z-index: 20;
    }

    /* --- 练习、错题重刷、收藏练习模式 --- */
    /* 第一行：移除、收藏、纠错（视模式自动隐藏其一，保留恰好2个） */
    body[data-mode="practice"] .quiz-sec-row,
    body[data-mode="mistakes"] .quiz-sec-row,
    body[data-mode="favorites"] .quiz-sec-row {
        display: grid;
        grid-template-columns: 1fr 1fr;
        gap: 12px;
        margin-top: 6px;    /* 下移两排按钮间隔的二分之一 */
        margin-bottom: 6px; /* 减小间距，保持整体结构紧凑 */
        width: 100%;
    }
    body[data-mode="practice"] #btn-remove-item,
    body[data-mode="favorites"] #btn-mark,
    body[data-mode="mistakes"] #btn-correction {
        display: none; /* 强制隐藏不属于本模式的按钮 */
    }
    body[data-mode="practice"] #btn-mark,
    body[data-mode="practice"] #btn-correction,
    body[data-mode="mistakes"] #btn-remove-item,
    body[data-mode="mistakes"] #btn-mark,
    body[data-mode="favorites"] #btn-remove-item,
    body[data-mode="favorites"] #btn-correction {
        width: 100%;
        margin: 0;
    }

    /* === 实践题 (主观题) 专属移动端布局覆盖 === */
    
    /* 1. 隐藏滑动文字中间的纠错图标（针对所有实践题页面） */
    body[data-category="practical"] #mobile-sub-correction,
    body[data-category="practical"] #mobile-sub-corr-sep {
        display: none;
    }

    /* 2. 预习页面的滑动文字距离恢复（抵消之前的负外边距），使其与练习页面一致 */
    body[data-category="practical"][data-mode="preview"] .swipe-hint {
        margin-top: 8px;
    }

    /* 3. 预习和练习页面：移除答题卡，强制显示纠错，且收藏与纠错等宽平分 */
    body[data-category="practical"][data-mode="preview"] #btn-exam-card,
    body[data-category="practical"][data-mode="practice"] #btn-exam-card {
        display: none; /* 实践题移除答题卡 */
    }
    
    body[data-category="practical"][data-mode="preview"] #btn-correction,
    body[data-category="practical"][data-mode="practice"] #btn-correction {
        display: inline-flex; /* 强制显示纠错 */
        justify-content: center;
        align-items: center;
    }

    body[data-category="practical"][data-mode="preview"] .quiz-sec-row,
    body[data-category="practical"][data-mode="practice"] .quiz-sec-row {
        display: grid;
        grid-template-columns: 1fr 1fr;
        gap: 12px;
        width: 100%;
    }
    
    body[data-category="practical"][data-mode="preview"] .quiz-sec-row > button,
    body[data-category="practical"][data-mode="practice"] .quiz-sec-row > button {
        flex: none;
        width: 100%;
        max-width: none;
        margin: 0;
    }

    /* 4. 隐藏预习和练习页面的答案按钮，调整练习页面主操作行 */
    body[data-category="practical"][data-mode="preview"] #btn-show-answer,
    body[data-category="practical"][data-mode="practice"] #btn-show-answer {
        display: none; /* 隐藏答案按钮 */
    }
    body[data-category="practical"][data-mode="practice"] .quiz-main-row {
        grid-template-columns: 1fr; /* 答案隐藏后，确保如果有按钮(如提交)能独占自适应 */
    }

    /* 5. 待复习页面 (review) 专属调整：纠错按钮和答案按钮并排显示，宽度一致 */
    body[data-category="practical"][data-mode="review"] .quiz-main-row {
        display: grid;
        grid-template-columns: 1fr 1fr;
        gap: 12px;
        width: 100%;
    }
    body[data-category="practical"][data-mode="review"] #btn-sub-correction,
    body[data-category="practical"][data-mode="review"] #btn-show-answer {
        display: inline-flex;
        flex: none;
        width: 100%;
        max-width: none;
        margin: 0;
        justify-content: center;
        align-items: center;
    }


    /* 第二行：答案与提交答案 */
    body[data-mode="practice"] .quiz-main-row,
    body[data-mode="mistakes"] .quiz-main-row,
    body[data-mode="favorites"] .quiz-main-row {
        display: grid;
        grid-template-columns: 1fr 1fr;
        gap: 12px;
        width: 100%;
    }
    body[data-mode="practice"] #btn-prev,
    body[data-mode="practice"] #btn-next,
    body[data-mode="practice"] #btn-sub-correction,
    body[data-mode="mistakes"] #btn-prev,
    body[data-mode="mistakes"] #btn-next,
    body[data-mode="mistakes"] #btn-sub-correction,
    body[data-mode="favorites"] #btn-prev,
    body[data-mode="favorites"] #btn-next,
    body[data-mode="favorites"] #btn-sub-correction { 
        display: none; 
    }
    body[data-mode="practice"] #btn-show-answer,
    body[data-mode="practice"] #btn-submit,
    body[data-mode="mistakes"] #btn-show-answer,
    body[data-mode="mistakes"] #btn-submit,
    body[data-mode="favorites"] #btn-show-answer,
    body[data-mode="favorites"] #btn-submit {
        width: 100%;
        margin: 0;
    }

    /* --- 考试界面 --- */
    body[data-mode="exam"] #btn-sub-correction,
    body[data-mode="exam"] #mobile-sub-correction { 
        display: none; 
    }
    body[data-mode="exam"] .swipe-hint {
        display: none; /* 隐藏底部居中的整段提示，改分布两侧 */
    }
    body[data-mode="exam"] .quiz-sec-row {
        display: flex;
        justify-content: center;
        gap: 12px;
        transform: translateY(6px); /* 强制位移，防止外边距塌陷导致无效 */
        margin-bottom: 6px; /* 并与下排按钮拉近距离 */
        width: 100%;
    }
    body[data-mode="exam"] .quiz-main-row {
        display: flex;
        justify-content: center;
        gap: 12px;
        margin-bottom: 12px;
        width: 100%;
    }
    body[data-mode="exam"] .quiz-main-row > button {
        flex: 0 0 calc((100% - 24px) / 3); /* 精确计算，与第一排的中间按钮(答题卡)等宽对齐 */
        width: calc((100% - 24px) / 3);
        max-width: none;
    }
    body[data-mode="exam"] .quiz-sec-row > button {
        flex: 1;
        max-width: 33%; /* 第一排有3个按钮，让它们匀称三等分 */
    }
    
    /* 第二排：分布滑动提示在两侧，交卷居中严格对齐第一排的中间 */
    body[data-mode="exam"] .quiz-main-row {
        display: grid;
        /* 第一排结构: W + gap + W + gap + W。让中间列恰为 W，两侧 1fr 刚好等于 W+gap，实现完美居中对齐 */
        grid-template-columns: 1fr calc((100% - 24px) / 3) 1fr;
        align-items: center;
        gap: 12px;
    }
    body[data-mode="exam"] #btn-prev,
    body[data-mode="exam"] #btn-next {
        display: block;
        background: transparent;
        border: none;
        box-shadow: none;
        color: var(--text-muted);
        font-size: 0; /* 隐藏原生文字 */
        width: 100%;
        padding: 0;
        margin: 0;
        text-align: center;
        pointer-events: none; /* 作为纯文本提示，禁止点击 */
    }
    body[data-mode="exam"] #btn-prev::before {
        content: "← 左滑下一题";
        font-size: 0.85rem; /* 与练习页面文字大小一致 */
        white-space: nowrap;
    }
    body[data-mode="exam"] #btn-next::before {
        content: "右滑上一题 →";
        font-size: 0.85rem;
        white-space: nowrap;
    }
    body[data-mode="exam"] #btn-submit {
        width: 100%;
        max-width: 100%;
        margin: 0;
    }
}

/* =============================================
   Desktop Layout (≥ 600px)
   ============================================= */
@media (min-width: 600px) {
    .container { max-width: 800px; padding: 40px 20px; }
    .card { padding: 36px; border-radius: 16px; }

    :root {
        --stat-box-padding: 18px;
        --stat-grid-mb: 22px;
        --setup-panel-padding: 22px;
        --setup-panel-mb: 22px;
        --form-input-padding: 11px;
        --form-input-fs: 0.95rem;
        --form-group-mb: 14px;
        --title-mb: 28px;
        --q-question-mb: 28px;
        --q-option-padding: 18px;
        --q-option-mb: 14px;
        --q-result-padding: 14px;
        --q-btn-gap: 14px;
    }

    h1 { font-size: 2rem; }
    h2 { font-size: 1.4rem; }
    .question-text { font-size: 1.35rem; }
    .btn { font-size: 1.05rem; padding: 15px; }
    .btn-action { width: 140px; height: 48px; padding: 0; display: flex; align-items: center; justify-content: center; }
    #btn-eyecare { padding: 6px 14px; font-size: 0.95rem; }

    .stat-box .value { font-size: 2rem; }
    .stat-box .label { font-size: 0.95rem; }
    .stat-box .prog, .stat-box .prev { font-size: 0.82rem; }

    #stat-single, #stat-multi, #stat-judge { font-size: 1.5rem; }
    .form-group label { font-size: 0.95rem; min-width: 50px; }
    .form-control { font-size: 0.95rem; }
}

/* =============================================
   纠错功能样式
   ============================================= */
.correction-tag-chk {
    display: inline-flex;
    align-items: center;
    gap: 5px;
    padding: 5px 12px;
    border: 1.5px solid var(--border-color);
    border-radius: 20px;
    font-size: 0.82rem;
    color: var(--text-main);
    cursor: pointer;
    transition: all 0.18s;
    user-select: none;
    -webkit-user-select: none;
}
.correction-tag-chk:active { opacity: 0.8; }
.correction-tag-chk input[type=checkbox] {
    accent-color: var(--danger);
    width: 14px; height: 14px;
}
.correction-tag-chk:has(input:checked) {
    border-color: var(--danger);
    background: rgba(239,68,68,0.08);
    color: var(--danger);
    font-weight: 600;
}
body.eye-care .correction-tag-chk:has(input:checked) {
    border-color: var(--primary);
    background: rgba(56,142,60,0.08);
    color: var(--primary);
}
#btn-correction { transition: background 0.15s; }
#btn-correction:hover { background: rgba(239,68,68,0.06); }

/* =============================================
   考试模式专用布局与响应式覆盖
   ============================================= */
.exam-mode .quiz-nav-btn {
    display: block;
}
.exam-mode .swipe-hint {
    display: none;
}

/* =============================================
   考试模式：仿真答题卡模态框网格系统
   ============================================= */
#exam-card-grid {
    display: grid;
    grid-template-columns: repeat(6, 1fr);
    gap: 8px;
    padding: 4px;
}
@media (min-width: 360px) {
    #exam-card-grid {
        grid-template-columns: repeat(7, 1fr);
    }
}
@media (min-width: 420px) {
    #exam-card-grid {
        grid-template-columns: repeat(8, 1fr);
    }
}
@media (min-width: 500px) {
    #exam-card-grid {
        grid-template-columns: repeat(10, 1fr);
        gap: 10px;
    }
}

.exam-grid-item {
    aspect-ratio: 1;
    display: flex;
    justify-content: center;
    align-items: center;
    border-radius: 50%;
    border: 1.5px solid var(--border-color);
    font-size: 0.9rem;
    font-weight: 500;
    cursor: pointer;
    transition: all 0.2s cubic-bezier(0.4, 0, 0.2, 1);
    background: transparent;
    color: var(--text-main);
    user-select: none;
    -webkit-user-select: none;
}
.exam-grid-item:hover {
    background: var(--hover-bg);
    transform: scale(1.08);
}
.exam-grid-item:active {
    transform: scale(0.95);
}

/* 当前做到的题号聚焦（发光粗蓝圈） */
.exam-grid-item.active {
    border-color: var(--primary);
    border-width: 2.5px;
    font-weight: 700;
    box-shadow: 0 0 10px rgba(9, 143, 241, 0.45);
    color: var(--primary);
    background: var(--card-bg);
}

/* 已作答（浅蓝背景主题蓝字） */
.exam-grid-item.answered {
    background-color: rgba(9, 143, 241, 0.12);
    border-color: var(--primary);
    color: var(--primary);
    font-weight: 600;
}

/* 已交卷回溯：答对项（浅绿背景绿字） */
.exam-grid-item.correct {
    background-color: rgba(40, 199, 111, 0.15);
    border-color: var(--success);
    color: var(--success);
    font-weight: 600;
}

/* 已交卷回溯：答错或未答项（浅红背景红字） */
.exam-grid-item.wrong {
    background-color: rgba(234, 84, 85, 0.15);
    border-color: var(--danger);
    color: var(--danger);
    font-weight: 600;
}

/* 护眼模式下的细微色调适配 */
body.eye-care .exam-grid-item.answered {
    background-color: rgba(56, 142, 60, 0.1);
    border-color: var(--primary);
    color: var(--primary);
}
body.eye-care .exam-grid-item.active {
    border-color: var(--primary);
    color: var(--primary);
    box-shadow: 0 0 10px rgba(56, 142, 60, 0.4);
}

/* =============================================
   Premium Modal 现代精致弹窗及其护眼适配
   ============================================= */
.premium-modal {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: rgba(0, 0, 0, 0.45);
    z-index: 1050;
    display: flex;
    justify-content: center;
    align-items: center;
    backdrop-filter: blur(8px);
    -webkit-backdrop-filter: blur(8px);
    opacity: 0;
    pointer-events: none;
    transition: opacity 0.3s cubic-bezier(0.4, 0, 0.2, 1);
}

.premium-modal.show {
    opacity: 1;
    pointer-events: auto;
}

.premium-modal-card {
    background: var(--card-bg);
    width: 90%;
    max-width: 380px;
    border-radius: 18px;
    padding: 32px 24px;
    box-shadow: 0 20px 40px rgba(0, 0, 0, 0.15);
    text-align: center;
    border: 1px solid var(--border-color);
    transform: scale(0.9);
    transition: transform 0.3s cubic-bezier(0.34, 1.56, 0.64, 1);
}

.premium-modal.show .premium-modal-card {
    transform: scale(1);
}

.premium-modal-icon {
    font-size: 2.8rem;
    margin-bottom: 12px;
    animation: premium-pulse 2s infinite ease-in-out;
    display: inline-block;
}

.premium-modal-title {
    margin-bottom: 8px;
    color: var(--text-main);
    font-size: 1.3rem;
    font-weight: 600;
}

.premium-modal-text {
    color: var(--text-muted);
    font-size: 0.95rem;
    line-height: 1.6;
    margin-bottom: 24px;
}

.premium-modal-actions {
    display: flex;
    flex-direction: column;
    gap: 12px;
}

/* 护眼模式高级适配 */
body.eye-care .premium-modal {
    background: rgba(27, 51, 32, 0.35); /* 柔和深绿透明遮罩 */
}

body.eye-care .premium-modal-card {
    box-shadow: 0 15px 30px rgba(27, 51, 32, 0.15);
    border: 1px solid var(--border-color);
}

body.eye-care .premium-modal .btn-danger {
    background-color: #C62828; /* 低饱和度温和红 */
    border-color: #C62828;
}

body.eye-care .premium-modal .btn-danger:hover {
    background-color: #B71C1C;
    border-color: #B71C1C;
}

@keyframes premium-pulse {
    0% { transform: scale(1); }
    50% { transform: scale(1.08); }
    100% { transform: scale(1); }
}

/* ===================== CSS 流光骨架屏样式 ===================== */
@keyframes shimmer-swipe {
    0% { background-position: 200% 0; }
    100% { background-position: -200% 0; }
}

.shimmer-box {
    background: linear-gradient(90deg, #f3f4f6 25%, #e5e7eb 50%, #f3f4f6 75%);
    background-size: 200% 100%;
    animation: shimmer-swipe 1.5s infinite linear;
    border-radius: 8px;
    display: inline-block;
}

body.eye-care .shimmer-box {
    background: linear-gradient(90deg, var(--bg-main) 25%, var(--border-color) 50%, var(--bg-main) 75%);
    background-size: 200% 100%;
}

.skeleton-title {
    width: 85%;
    height: 28px;
    margin-bottom: 24px;
    display: block;
}

.skeleton-option {
    width: 100%;
    height: 52px;
    margin-bottom: 16px;
    display: block;
}

.skeleton-btn {
    width: 120px;
    height: 42px;
    border-radius: 20px;
    display: inline-block;
}

#quiz-actual-content, #quiz-skeleton-content {
    transition: opacity 0.3s cubic-bezier(0.4, 0, 0.2, 1);
    word-break: break-all;
    overflow-wrap: break-word;
}

.fade-hidden {
    opacity: 0;
    pointer-events: none;
}

.fade-visible {
    opacity: 1;
}

/* 手动清除缓存按钮微交互 */
#btn-clear-cache {
    background: transparent;
    border: 1px solid var(--border-color);
    color: var(--text-muted);
    padding: 6px 12px;
    border-radius: 20px;
    font-size: 0.85rem;
    display: inline-flex;
    align-items: center;
    gap: 6px;
    cursor: pointer;
    transition: all 0.2s cubic-bezier(0.4, 0, 0.2, 1);
    margin: 8px auto;
}

#btn-clear-cache:hover {
    color: var(--primary);
    border-color: var(--primary);
    background: var(--hover-bg);
}

#btn-clear-cache:active {
    transform: scale(0.95);
}

/* 主观题遮罩效果 */
.blur-text {
    background-image: radial-gradient(#999 15%, transparent 16%), radial-gradient(#999 15%, transparent 16%);
    background-size: 8px 8px;
    background-position: 0 0, 4px 4px;
    color: transparent;
    text-shadow: none;
    user-select: none;
    cursor: pointer;
    transition: all 0.3s ease;
    border-radius: 4px;
    padding: 2px 4px;
    word-break: break-all;
}

.blur-text:hover {
    background-color: rgba(0, 0, 0, 0.05);
}

.blur-text.revealed {
    background: none;
    color: inherit;
    cursor: default;
    user-select: text;
}

/* 提示模式下的高亮关键词 */
.blur-text.hinted .keyword {
    color: var(--primary);
    background: rgba(24, 144, 255, 0.1);
    text-shadow: none;
}

/* 计算题手风琴 */
.accordion-step {
    border: 1px solid var(--border-color);
    border-radius: 8px;
    margin-bottom: 8px;
    overflow: hidden;
    width: 100%;
    box-sizing: border-box;
}

.accordion-header {
    background: var(--card-bg);
    padding: 12px;
    font-weight: bold;
    cursor: pointer;
    display: flex;
    justify-content: space-between;
    align-items: center;
    word-break: break-all;
}

.accordion-content {
    max-height: 0;
    overflow: hidden;
    transition: max-height 0.4s ease-out;
    background: var(--body-bg);
}

.accordion-content.expanded {
    max-height: 500px; /* 大约的最大高度 */
    border-top: 1px solid var(--border-color);
}

.accordion-content-inner {
    padding: 12px;
    word-break: break-all;
    white-space: pre-wrap;
    overflow-x: hidden;
}

/* 拖拽排序项 */
.draggable-item {
    padding: 12px;
    margin-bottom: 8px;
    background: transparent;
    border: 1px solid var(--border-color);
    border-radius: 6px;
    cursor: grab;
    display: flex;
    align-items: flex-start;
    gap: 10px;
    word-break: break-all;
}

.draggable-item.dragging {
    opacity: 0.5;
}

.draggable-item .drag-handle {
    color: #999;
    font-size: 1.2rem;
    cursor: grab;
}

.draggable-item input[type="number"] {
    width: 50px;
    padding: 4px;
    text-align: center;
    border: 1px solid #ccc;
    border-radius: 4px;
}

/* 答题界面及主观评价按钮自适应 */
@media (max-width: 600px) {
    .btn {
        padding: 3.46vw;
        border-radius: 2.13vw;
        font-size: 4vw;
        margin-bottom: 3.2vw;
    }
    .quiz-sec-btn {
        padding: 2.93vw 1.6vw;
        font-size: 3.6vw;
    }
    .quiz-nav-btn, .quiz-submit-btn {
        padding: 2.93vw 1.6vw;
        font-size: 3.8vw;
    }
    #subjective-eval-btns {
        gap: 2.13vw;
    }
    #subjective-action-row {
        gap: 2.66vw;
    }
}

/* =========================================
   高级互动遮罩外观效果
   ========================================= */

/* 1. 机密涂黑 (Redact) */
.mask-redact {
    position: relative;
    color: transparent;
    display: inline-block;
    cursor: pointer;
    transition: color 0.4s ease;
    user-select: none;
    -webkit-user-select: none;
    border-radius: 4px;
    padding: 2px 4px;
}
.mask-redact::before {
    content: '';
    position: absolute;
    top: 0; left: 0; right: 0; bottom: 0;
    background-color: #1a1a1a;
    border-radius: 4px;
    transform-origin: center;
    transition: transform 0.5s cubic-bezier(0.8, 0, 0.2, 1), opacity 0.5s ease;
    box-shadow: 0 2px 5px rgba(0,0,0,0.4);
    z-index: 1;
}
body.eye-care .mask-redact::before {
    background-color: #2c3e35;
}
.mask-redact::after {
    content: 'CLASSIFIED';
    position: absolute;
    top: 50%; left: 50%;
    transform: translate(-50%, -50%);
    font-size: 0.6rem;
    color: rgba(255,255,255,0.15);
    letter-spacing: 2px;
    font-family: monospace;
    font-weight: bold;
    z-index: 2;
    pointer-events: none;
    transition: opacity 0.3s ease;
}
.mask-redact:hover, .mask-redact.revealed {
    color: var(--text-main);
}
.mask-redact:hover::before, .mask-redact.revealed::before {
    transform: scaleX(0);
    opacity: 0;
}
.mask-redact:hover::after, .mask-redact.revealed::after {
    opacity: 0;
}

/* 2. 赛博解码 (Glitch) */
.mask-glitch {
    position: relative;
    color: transparent;
    display: inline-block;
    cursor: pointer;
    background: repeating-linear-gradient(
        45deg,
        rgba(0,0,0,0.1),
        rgba(0,0,0,0.1) 5px,
        rgba(0,0,0,0.2) 5px,
        rgba(0,0,0,0.2) 10px
    );
    filter: contrast(1.5) brightness(0.8);
    transition: all 0.3s steps(3);
    border-radius: 4px;
    padding: 2px 4px;
}
body.eye-care .mask-glitch {
    background: repeating-linear-gradient(
        45deg,
        rgba(56, 142, 60, 0.1),
        rgba(56, 142, 60, 0.1) 5px,
        rgba(56, 142, 60, 0.2) 5px,
        rgba(56, 142, 60, 0.2) 10px
    );
}
.mask-glitch:hover, .mask-glitch.revealed {
    color: var(--text-main);
    background: transparent;
    filter: none;
    animation: glitch-anim 0.4s cubic-bezier(.25, .46, .45, .94) both;
}
@keyframes glitch-anim {
    0% { transform: translate(0); text-shadow: none; }
    20% { transform: translate(-3px, 2px); text-shadow: 3px 0 #ff00c1, -3px 0 #00fff9; }
    40% { transform: translate(3px, -2px); text-shadow: 3px 0 #00fff9, -3px 0 #ff00c1; }
    60% { transform: translate(-2px, 0); text-shadow: -2px 0 #ff00c1, 2px 0 #00fff9; }
    80% { transform: translate(2px, 2px); text-shadow: 2px 0 #00fff9, -2px 0 #ff00c1; }
    100% { transform: translate(0); text-shadow: none; }
}

/* 3. 银河刮刮乐 (Scratch) */
.mask-scratch {
    position: relative;
    color: transparent;
    display: inline-block;
    cursor: pointer;
    transition: color 0.6s ease 0.2s;
    user-select: none;
    -webkit-user-select: none;
    padding: 2px 4px;
}
.mask-scratch::before {
    content: '';
    position: absolute;
    top: 0; left: -2%; right: -2%; bottom: 0;
    background: linear-gradient(135deg, #e0e0e0 25%, #c0c0c0 50%, #e0e0e0 75%);
    background-size: 200% 200%;
    border-radius: 3px;
    z-index: 1;
    transition: clip-path 0.8s cubic-bezier(0.1, 0.7, 0.1, 1), opacity 0.8s ease;
    clip-path: polygon(0 0, 100% 0, 100% 100%, 0 100%);
    box-shadow: inset 0 0 8px rgba(255,255,255,0.8), 0 2px 4px rgba(0,0,0,0.1);
}
body.eye-care .mask-scratch::before {
    background: linear-gradient(135deg, #a5d6a7 25%, #81c784 50%, #a5d6a7 75%);
}
.mask-scratch::after {
    content: '';
    position: absolute;
    top: 0; left: -2%; right: -2%; bottom: 0;
    background-image: repeating-linear-gradient(45deg, transparent, transparent 4px, rgba(255,255,255,0.4) 4px, rgba(255,255,255,0.4) 8px);
    z-index: 2;
    opacity: 0.7;
    pointer-events: none;
    transition: opacity 0.4s;
}
.mask-scratch:hover, .mask-scratch.revealed {
    color: var(--text-main);
}
.mask-scratch:hover::before, .mask-scratch.revealed::before {
    clip-path: polygon(100% 0, 100% 0, 100% 100%, 100% 100%);
    opacity: 0.2;
}
.mask-scratch:hover::after, .mask-scratch.revealed::after {
    opacity: 0;
}


/* 4. 极光冰霜 (Aurora) */
.mask-aurora {
    position: relative;
    display: inline-block;
    cursor: pointer;
    user-select: none;
    -webkit-user-select: none;
    padding: 4px 8px;
    border-radius: 8px;
    
    /* 核心：文字变成高度模糊 */
    color: transparent;
    text-shadow: 0 0 14px rgba(0, 0, 0, 0.65);
    
    /* 高级外框材质 */
    border: 1px solid rgba(255, 255, 255, 0.4);
    background: linear-gradient(135deg, rgba(255,255,255,0.2) 0%, rgba(255,255,255,0.05) 100%);
    box-shadow: inset 0 1px 1px rgba(255,255,255,0.5), 0 8px 24px rgba(0,0,0,0.08);
    
    overflow: hidden;
    transition: all 0.6s cubic-bezier(0.2, 0.8, 0.2, 1);
}

/* 内部极其微弱的流动极光 */
.mask-aurora::after {
    content: '';
    position: absolute;
    top: -50%; left: -50%; width: 200%; height: 200%;
    background: radial-gradient(circle at 50% 50%, rgba(9, 143, 241, 0.15) 0%, rgba(138, 43, 226, 0.1) 30%, transparent 60%);
    animation: aurora-flow 6s ease-in-out infinite alternate;
    pointer-events: none;
    z-index: -1;
    opacity: 1;
    transition: opacity 0.5s ease;
}

body.eye-care .mask-aurora {
    text-shadow: 0 0 14px rgba(56, 142, 60, 0.85);
    border: 1px solid rgba(165, 214, 167, 0.3);
    background: linear-gradient(135deg, rgba(165,214,167,0.15) 0%, transparent 100%);
}
body.eye-care .mask-aurora::after {
    background: radial-gradient(circle at 50% 50%, rgba(56, 142, 60, 0.2) 0%, rgba(129, 199, 132, 0.1) 30%, transparent 60%);
}

.mask-aurora:hover, .mask-aurora.revealed {
    color: var(--text-main);
    text-shadow: none;
    background: transparent;
    border-color: transparent;
    box-shadow: none;
}
.mask-aurora:hover::after, .mask-aurora.revealed::after {
    opacity: 0;
}

@keyframes aurora-flow {
    0% { transform: translate(0, 0) scale(1); }
    100% { transform: translate(15%, 10%) scale(1.1); }
}

/* ==========================================================================
   Modals & Overlays (Phase 1 Refactoring)
   ========================================================================== */
.modal-overlay {
    display: flex;
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: rgba(0,0,0,0.5);
    z-index: 9999;
    justify-content: center;
    align-items: center;
}
.modal-container {
    background: var(--card-bg);
    border-radius: 12px;
    box-shadow: 0 8px 32px rgba(0,0,0,0.3);
}
.modal-container-lg {
    width: 90%;
    max-width: 440px;
    max-height: 85vh;
    overflow-y: auto;
    padding: 20px 24px;
}
.modal-container-sm {
    width: 85%;
    max-width: 350px;
    padding: 20px;
    text-align: center;
}
.modal-header {
    color: var(--text-main);
    font-size: 1.1rem;
    margin-bottom: 12px;
}
.modal-header-lg {
    color: var(--text-main);
    font-size: 1.2rem;
    margin-top: 0;
    margin-bottom: 20px;
    text-align: center;
}
.modal-msg {
    margin-bottom: 20px;
    color: var(--text-muted);
    font-size: 0.95rem;
}

/* ==========================================================================
   Utility Classes (Phase 2 & 3 Refactoring)
   ========================================================================== */
/* Display Utilities */
.d-flex { display: flex; }
.d-flex-col { display: flex; flex-direction: column; }
.d-grid { display: grid; }

/* Flex alignment utilities */
.justify-between { justify-content: space-between; }
.justify-center { justify-content: center; }
.align-center { align-items: center; }
.align-stretch { align-items: stretch; }

/* Spacing utilities (margin) */
.mb-0 { margin-bottom: 0 !important; }
.mb-10 { margin-bottom: 10px; }
.mb-12 { margin-bottom: 12px; }
.mb-14 { margin-bottom: 14px; }
.mb-20 { margin-bottom: 20px; }
.mb-24 { margin-bottom: 24px; }
.mt-0 { margin-top: 0 !important; }
.mt-4 { margin-top: 4px; }
.mt-5 { margin-top: 5px; }

/* Gap utilities */
.gap-6 { gap: 6px; }
.gap-10 { gap: 10px; }
.gap-12 { gap: 12px; }

/* Typography utilities */
.fs-sm { font-size: 0.9rem; }
.fs-xs { font-size: 0.82rem; font-weight: bold; }
.fs-btn { font-size: 0.88rem; }

/* ==========================================================================
   Utility Classes (Phase 3 Buttons)
   ========================================================================== */
.w-100 { width: 100%; }
.flex-1 { flex: 1; }
.h-40 { height: 40px; }
.mt-15 { margin-top: 15px; }
.btn-flex-center { 
    display: flex; 
    align-items: center; 
    justify-content: center; 
}

.d-none { display: none !important; }