@import url('https://fonts.googleapis.com/css2?family=Inter:wght@400;800&family=Lexend:wght@700&family=JetBrains+Mono:ital,wght@1,800&display=swap');

/* ========================================
   CSS Variables - Dark Theme (Default)
   ======================================== */
:root {
    --bg: #030712;
    --bg-secondary: #0f172a;
    --glass: rgba(17, 24, 39, 0.85);
    --accent: #6366f1;
    --accent-hover: #818cf8;
    --accent-glow: rgba(99, 102, 241, 0.5);
    --accent-subtle: rgba(99, 102, 241, 0.1);
    --text-main: #f9fafb;
    --text-muted: #94a3b8;
    --text-dim: #4b5563;
    --sidebar-w: 300px;
    --card-bg: rgba(30, 41, 59, 0.3);
    --border-subtle: rgba(255, 255, 255, 0.05);
    --border-light: rgba(255, 255, 255, 0.08);
    --input-bg: #0f172a;
    --success: #10b981;
    --success-subtle: rgba(16, 185, 129, 0.1);
    --warning: #f59e0b;
    --danger: #ef4444;
    --danger-subtle: rgba(239, 68, 68, 0.1);
    --shadow-lg: 0 25px 50px -12px rgba(0, 0, 0, 0.5);
    --transition-smooth: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
}

/* ========================================
   Light Theme
   ======================================== */
[data-theme="light"] {
    --bg: #f1f5f9;
    --bg-secondary: #e2e8f0;
    --glass: rgba(255, 255, 255, 0.85);
    --accent: #4f46e5;
    --accent-hover: #6366f1;
    --accent-glow: rgba(79, 70, 229, 0.3);
    --accent-subtle: rgba(79, 70, 229, 0.08);
    --text-main: #0f172a;
    --text-muted: #475569;
    --text-dim: #94a3b8;
    --card-bg: rgba(255, 255, 255, 0.7);
    --border-subtle: rgba(0, 0, 0, 0.06);
    --border-light: rgba(0, 0, 0, 0.1);
    --input-bg: #f8fafc;
    --success: #059669;
    --success-subtle: rgba(5, 150, 105, 0.08);
    --warning: #d97706;
    --danger: #dc2626;
    --danger-subtle: rgba(220, 38, 38, 0.08);
    --shadow-lg: 0 25px 50px -12px rgba(0, 0, 0, 0.15);
}

/* ========================================
   Global Reset & Base
   ======================================== */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

#app {
    display: flex;
    width: 100%;
    height: 100vh;
}

body {
    background: var(--bg);
    background-image:
        radial-gradient(at 0% 0%, rgba(99, 102, 241, 0.15) 0%, transparent 50%),
        radial-gradient(at 100% 100%, rgba(168, 85, 247, 0.12) 0%, transparent 50%);
    color: var(--text-main);
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
    height: 100vh;
    display: flex;
    overflow: auto;
    transition: background 0.4s ease, color 0.4s ease;
}

[data-theme="light"] #app {
    display: flex;
    width: 100%;
    height: 100vh;
}

body {
    background-image:
        radial-gradient(at 0% 0%, rgba(99, 102, 241, 0.08) 0%, transparent 50%),
        radial-gradient(at 100% 100%, rgba(168, 85, 247, 0.06) 0%, transparent 50%);
}

/* ========================================
   Scrollbar Styling
   ======================================== */
::-webkit-scrollbar {
    width: 6px;
    height: 6px;
}
::-webkit-scrollbar-track {
    background: transparent;
}
::-webkit-scrollbar-thumb {
    background: rgba(99, 102, 241, 0.3);
    border-radius: 3px;
}
::-webkit-scrollbar-thumb:hover {
    background: rgba(99, 102, 241, 0.5);
}

/* ========================================
   Sidebar
   ======================================== */
.sidebar {
    width: var(--sidebar-w);
    height: 100%;
    background: var(--glass);
    backdrop-filter: blur(25px);
    border-right: 1px solid var(--border-subtle);
    display: flex;
    flex-direction: column;
    transition: all 0.5s cubic-bezier(0.4, 0, 0.2, 1);
    position: fixed;
    left: 0;
    top: 0;
    z-index: 1000;
}

.sidebar.collapsed {
    width: 0;
    transform: translateX(calc(var(--sidebar-w) * -1));
}

.sidebar-inner {
    width: var(--sidebar-w);
    height: 100%;
    overflow-y: auto;
    padding: 25px 15px;
    transition: 0.3s;
}

.sidebar.collapsed .sidebar-inner {
    opacity: 0;
    pointer-events: none;
}

.toggle-tab {
    position: absolute;
    right: -32px;
    top: 30px;
    width: 32px;
    height: 60px;
    background: var(--accent);
    color: white;
    cursor: pointer;
    border-radius: 0 12px 12px 0;
    display: flex;
    align-items: center;
    justify-content: center;
    box-shadow: 5px 0 15px var(--accent-glow);
    transition: 0.3s;
}

.sidebar.collapsed .toggle-tab {
    transform: translateX(var(--sidebar-w));
}

/* ========================================
   Main Container
   ======================================== */
.main-container {
    flex: 1;
    display: flex;
    flex-direction: column;
    padding: 20px 30px;
    position: relative;
    overflow: auto;
    margin-left: var(--sidebar-w);
    z-index: 1;
    height: 100vh;
}

.main-container.full-width {
    margin-left: 0;
}

.main-title {
    text-align: center;
    font-size: 2.2rem;
    font-weight: 800;
    margin-bottom: 15px;
    text-transform: uppercase;
    letter-spacing: -2px;
    background: linear-gradient(180deg, #fff 0%, #a5b4fc 100%);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    filter: drop-shadow(0 0 20px rgba(99, 102, 241, 0.4));
}

[data-theme="light"] .main-title {
    background: linear-gradient(180deg, #1e293b 0%, #4f46e5 100%);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    filter: drop-shadow(0 0 10px rgba(79, 70, 229, 0.2));
}

/* ========================================
   Top Info Bar
   ======================================== */
.top-info-bar {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 20px;
    padding: 12px 20px;
    background: var(--glass);
    border-radius: 16px;
    border: 1px solid var(--border-subtle);
    backdrop-filter: blur(15px);
}

.date-time {
    font-size: 0.95rem;
    color: var(--text-muted);
}

.weather-location {
    display: flex;
    align-items: center;
    gap: 10px;
    font-size: 0.95rem;
}

.user-status {
    font-size: 0.9rem;
    color: #a5b4fc;
    display: flex;
    align-items: center;
    gap: 10px;
}

.logout-btn {
    background: var(--danger-subtle);
    color: var(--danger);
    border: none;
    padding: 5px 12px;
    border-radius: 8px;
    cursor: pointer;
    font-size: 0.85rem;
    transition: var(--transition-smooth);
}
.logout-btn:hover {
    background: var(--danger);
    color: white;
}

/* ========================================
   Stats Bar (Enhanced)
   ======================================== */
.stats-bar {
    display: flex;
    justify-content: space-around;
    background: var(--glass);
    padding: 16px 20px;
    border-radius: 18px;
    margin-bottom: 20px;
    border: 1px solid var(--border-light);
    backdrop-filter: blur(15px);
    flex-wrap: wrap;
    gap: 12px;
}

.stat-item {
    font-size: 14px;
    color: var(--text-muted);
    font-weight: 500;
    display: flex;
    align-items: center;
    gap: 6px;
    background: var(--accent-subtle);
    padding: 8px 16px;
    border-radius: 10px;
    border: 1px solid transparent;
    transition: var(--transition-smooth);
}
.stat-item:hover {
    border-color: var(--accent);
    transform: translateY(-2px);
}
.stat-item span {
    color: #a5b4fc;
    font-weight: bold;
    font-size: 1.1rem;
}

/* ========================================
   Study Tip Box
   ======================================== */
.tip-box {
    background: var(--accent-subtle);
    border-left: 3px solid var(--accent);
    padding: 15px 20px;
    margin: 20px 0;
    border-radius: 0 12px 12px 0;
    font-size: 1rem;
    color: var(--text-muted);
    transition: var(--transition-smooth);
}

.tip-title {
    font-weight: 700;
    color: var(--accent);
    margin-bottom: 5px;
}

/* ========================================
   Study Card (Main Word Display)
   ======================================== */
.study-card {
    background: var(--card-bg);
    border-radius: 25px;
    border: 1px solid var(--border-light);
    flex: 1;
    display: flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;
    position: relative;
    padding: 40px;
    box-shadow: 0 50px 100px rgba(0, 0, 0, 0.5);
    backdrop-filter: blur(15px);
    transition: 0.4s cubic-bezier(0.175, 0.885, 0.32, 1.275);
    min-height: 400px;
}

[data-theme="light"] .study-card {
    box-shadow: 0 50px 100px rgba(0, 0, 0, 0.1);
}

.card-anim {
    transform: scale(0.96);
    opacity: 0;
    filter: blur(10px);
}

.top-meta {
    position: absolute;
    top: 40px;
    left: 55px;
    right: 55px;
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.word-badge {
    background: var(--accent);
    color: white;
    padding: 5px 22px;
    border-radius: 12px;
    font-family: 'JetBrains Mono', monospace;
    font-size: 1.3rem;
    font-style: italic;
    font-weight: 800;
    box-shadow: 0 5px 20px var(--accent-glow);
}

.star-btn {
    position: absolute;
    top: 20px;
    right: 25px;
    font-size: 1.8rem;
    cursor: pointer;
    color: rgba(255, 255, 255, 0.05);
    transition: 0.3s;
    z-index: 10;
}
.star-btn.active {
    color: #fbbf24;
    filter: drop-shadow(0 0 15px rgba(251, 191, 36, 0.6));
}
[data-theme="light"] .star-btn {
    color: rgba(0, 0, 0, 0.08);
}

.indo-box {
    font-size: 6rem;
    font-weight: 900;
    margin-bottom: 10px;
    text-align: center;
    background: linear-gradient(to bottom, #fff, #94a3b8);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
}

[data-theme="light"] .indo-box {
    background: linear-gradient(to bottom, #1e293b, #6366f1);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
}

.zh-box {
    font-size: 2.6rem;
    color: var(--text-muted);
    font-weight: 300;
    letter-spacing: 5px;
    transition: var(--transition-smooth);
}

/* ========================================
   Navigation Buttons
   ======================================== */
.nav-row {
    display: flex;
    gap: 40px;
    margin-top: 50px;
}

.circle-btn {
    width: 80px;
    height: 80px;
    border-radius: 50%;
    border: none;
    background: rgba(255, 255, 255, 0.03);
    color: white;
    font-size: 2rem;
    cursor: pointer;
    transition: 0.3s;
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    border: 1px solid var(--border-subtle);
}

.circle-btn:hover {
    background: var(--accent);
    transform: translateY(-5px);
    box-shadow: 0 10px 20px var(--accent-glow);
}

[data-theme="light"] .circle-btn {
    background: var(--card-bg);
    color: var(--text-main);
    border: 1px solid var(--border-light);
}

.play-btn {
    width: 100px;
    height: 100px;
    background: var(--accent);
    box-shadow: 0 0 40px var(--accent-glow);
}

/* ========================================
   Control Panel
   ======================================== */
.control-panel {
    width: 100%;
    margin: 35px auto 0;
    background: var(--glass);
    padding: 30px 50px;
    border-radius: 35px;
    border: 1px solid var(--border-light);
    display: flex;
    flex-direction: column;
    gap: 25px;
    backdrop-filter: blur(15px);
}

.ctrl-row {
    display: flex;
    align-items: center;
    justify-content: space-between;
}

.ctrl-label {
    font-size: 1.05rem;
    color: var(--text-muted);
    font-weight: 600;
    letter-spacing: 1px;
}

.ctrl-value {
    min-width: 80px;
    text-align: right;
    font-family: 'Lexend', sans-serif;
    color: var(--accent);
    font-weight: 700;
    font-size: 1.3rem;
    text-shadow: 0 0 12px var(--accent-glow);
}

[data-theme="light"] .ctrl-value {
    text-shadow: none;
}

.switch {
    position: relative;
    width: 52px;
    height: 28px;
}

.switch input {
    opacity: 0;
    width: 0;
    height: 0;
}

.slider {
    position: absolute;
    cursor: pointer;
    inset: 0;
    background: #1e293b;
    transition: .4s;
    border-radius: 34px;
    border: 1px solid var(--border-subtle);
}

[data-theme="light"] .slider {
    background: #cbd5e1;
}

.slider:before {
    position: absolute;
    content: "";
    height: 20px;
    width: 20px;
    left: 4px;
    bottom: 3px;
    background: white;
    transition: .4s;
    border-radius: 50%;
    box-shadow: 0 2px 4px rgba(0,0,0,0.2);
}

input:checked + .slider {
    background: var(--accent);
}

input:checked + .slider:before {
    transform: translateX(24px);
}

/* ========================================
   Copyright & Footer
   ======================================== */
.copyright {
    font-size: 0.9rem;
    text-align: center;
    color: var(--text-dim);
    margin-top: 35px;
    letter-spacing: 0.5px;
}

.clickable {
    color: var(--accent);
    cursor: pointer;
    font-weight: 700;
    transition: 0.2s;
}

.clickable:hover {
    text-shadow: 0 0 10px var(--accent-glow);
    text-decoration: underline;
}

/* ========================================
   Modals
   ======================================== */
.modal-overlay {
    display: none;
    position: fixed;
    inset: 0;
    background: rgba(0, 0, 0, 0.9);
    z-index: 2000;
    justify-content: center;
    align-items: center;
    backdrop-filter: blur(15px);
}

[data-theme="light"] .modal-overlay {
    background: rgba(0, 0, 0, 0.5);
}

.modal-content {
    background: var(--bg-secondary);
    padding: 40px;
    border-radius: 30px;
    border: 1px solid var(--accent);
    text-align: center;
    color: var(--text-main);
    transition: var(--transition-smooth);
}

[data-theme="light"] .modal-content {
    background: #ffffff;
}

/* ========================================
   Sidebar Menu Items
   ======================================== */
.cat-item {
    margin-bottom: 12px;
    border-radius: 14px;
    background: rgba(255, 255, 255, 0.03);
    transition: var(--transition-smooth);
}
.cat-item:hover {
    background: rgba(255, 255, 255, 0.06);
}

[data-theme="light"] .cat-item {
    background: rgba(0, 0, 0, 0.03);
}
[data-theme="light"] .cat-item:hover {
    background: rgba(0, 0, 0, 0.06);
}

.cat-head {
    padding: 12px 15px;
    cursor: pointer;
    font-weight: 600;
    display: flex;
    justify-content: space-between;
    color: var(--text-main);
}

.sub-menu {
    display: none;
    padding: 10px;
}

.sub-menu.active {
    display: block;
}

/* Word list in sidebar */
.sub-word-list {
    display: none;
    border-left: 1px solid var(--border-subtle);
    margin-left: 10px;
}
.sub-word-list.active {
    display: block;
}
.sub-word-list div {
    padding: 4px 8px;
    border-radius: 6px;
    transition: var(--transition-smooth);
    cursor: pointer;
}
.sub-word-list div:hover {
    background: var(--accent-subtle);
    color: #a5b4fc;
}

/* ========================================
   Study Record
   ======================================== */
.study-record-box {
    background: var(--glass);
    border-radius: 20px;
    padding: 20px;
    margin: 20px 0;
    border: 1px solid var(--border-subtle);
    backdrop-filter: blur(15px);
}

.record-title {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 15px;
    font-size: 1.2rem;
    font-weight: 700;
    color: var(--text-main);
}

.clear-record-btn {
    background: var(--danger-subtle);
    color: var(--danger);
    border: none;
    padding: 5px 12px;
    border-radius: 8px;
    cursor: pointer;
    font-size: 0.85rem;
    transition: var(--transition-smooth);
}
.clear-record-btn:hover {
    background: var(--danger);
    color: white;
}

.record-list {
    max-height: 150px;
    overflow-y: auto;
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 10px;
}

.record-item {
    padding: 8px 12px;
    background: var(--card-bg);
    border-radius: 10px;
    font-size: 0.9rem;
    border: 1px solid var(--border-subtle);
    transition: var(--transition-smooth);
}
.record-item:hover {
    border-color: var(--accent);
    transform: translateY(-1px);
}

.record-indo {
    color: #a5b4fc;
    font-weight: 600;
}

.record-zh {
    color: var(--text-muted);
    font-size: 0.85rem;
}

/* ========================================
   Share Modal
   ======================================== */
.share-modal-content {
    width: 500px;
    padding: 30px;
}

.share-card {
    background: linear-gradient(135deg, #1e293b 0%, #0f172a 100%);
    border-radius: 20px;
    padding: 30px;
    margin-bottom: 20px;
    text-align: left;
}

[data-theme="light"] .share-card {
    background: linear-gradient(135deg, #e0e7ff 0%, #c7d2fe 100%);
}

.share-header {
    font-size: 1.5rem;
    font-weight: 800;
    margin-bottom: 15px;
}

.share-stats {
    margin: 12px 0;
    line-height: 1.6;
    color: #cbd5e1;
}

.share-tip {
    font-size: 0.95rem;
    color: #a5b4fc;
    margin-bottom: 15px;
}

.share-record {
    font-size: 0.9rem;
    color: var(--text-muted);
    margin-bottom: 10px;
}

.share-copy-btn, .share-save-btn {
    background: var(--accent);
    color: white;
    border: none;
    padding: 10px 20px;
    border-radius: 10px;
    cursor: pointer;
    margin: 0 5px;
    transition: var(--transition-smooth);
}
.share-copy-btn:hover, .share-save-btn:hover {
    background: var(--accent-hover);
    transform: translateY(-2px);
}

/* ========================================
   Theme Toggle Button
   ======================================== */
.theme-toggle {
    position: fixed;
    bottom: 25px;
    right: 25px;
    width: 48px;
    height: 48px;
    border-radius: 50%;
    background: var(--accent);
    color: white;
    border: none;
    cursor: pointer;
    font-size: 1.2rem;
    display: flex;
    align-items: center;
    justify-content: center;
    box-shadow: 0 5px 20px var(--accent-glow);
    z-index: 999;
    transition: var(--transition-smooth);
}
.theme-toggle:hover {
    transform: translateY(-3px) rotate(15deg);
    box-shadow: 0 8px 25px var(--accent-glow);
}

/* ========================================
   Practice Mode Styles
   ======================================== */
.practice-container {
    background: var(--glass);
    border-radius: 25px;
    border: 1px solid var(--border-light);
    padding: 30px;
    backdrop-filter: blur(15px);
    margin: 0;
}

.practice-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 25px;
    padding-bottom: 15px;
    border-bottom: 1px solid var(--border-subtle);
}

.practice-title {
    font-size: 1.4rem;
    font-weight: 700;
    color: var(--text-main);
}

.practice-type-selector {
    display: flex;
    gap: 8px;
}

.practice-type-btn {
    padding: 8px 16px;
    border-radius: 10px;
    border: 1px solid var(--border-light);
    background: transparent;
    color: var(--text-muted);
    cursor: pointer;
    font-size: 0.85rem;
    transition: var(--transition-smooth);
}
.practice-type-btn:hover, .practice-type-btn.active {
    background: var(--accent-subtle);
    color: #a5b4fc;
    border-color: var(--accent);
}

.practice-score-bar {
    display: flex;
    justify-content: space-around;
    margin-bottom: 25px;
    padding: 12px;
    background: var(--accent-subtle);
    border-radius: 12px;
}

.practice-score-item {
    text-align: center;
    color: var(--text-muted);
    font-size: 0.85rem;
}
.practice-score-item .score-value {
    font-size: 1.4rem;
    font-weight: 700;
    color: #a5b4fc;
    display: block;
    margin-bottom: 2px;
}

.practice-question-box {
    background: var(--card-bg);
    border-radius: 20px;
    padding: 40px 30px;
    text-align: center;
    margin-bottom: 25px;
    border: 1px solid var(--border-subtle);
}

.practice-question-label {
    font-size: 0.85rem;
    color: var(--text-muted);
    margin-bottom: 10px;
}

.practice-question-word {
    font-size: 3rem;
    font-weight: 800;
    margin-bottom: 8px;
    background: linear-gradient(to bottom, #fff, #a5b4fc);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
}

[data-theme="light"] .practice-question-word {
    background: linear-gradient(to bottom, #1e293b, #4f46e5);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
}

.practice-question-hint {
    font-size: 0.9rem;
    color: var(--text-dim);
}

.practice-options {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 12px;
    margin-bottom: 20px;
}

.practice-option {
    padding: 16px 20px;
    border-radius: 14px;
    border: 2px solid var(--border-light);
    background: var(--card-bg);
    color: var(--text-main);
    cursor: pointer;
    font-size: 1rem;
    transition: var(--transition-smooth);
    text-align: center;
}
.practice-option:hover {
    border-color: var(--accent);
    background: var(--accent-subtle);
    transform: translateY(-2px);
}
.practice-option.correct {
    border-color: var(--success);
    background: var(--success-subtle);
    color: var(--success);
    font-weight: 700;
}
.practice-option.wrong {
    border-color: var(--danger);
    background: var(--danger-subtle);
    color: var(--danger);
}
.practice-option.disabled {
    pointer-events: none;
    opacity: 0.6;
}

.practice-input-box {
    display: none;
    margin-bottom: 20px;
    text-align: center;
}
.practice-input-box.active {
    display: block;
}
.practice-input {
    width: 100%;
    max-width: 400px;
    padding: 14px 20px;
    border-radius: 14px;
    border: 2px solid var(--border-light);
    background: var(--input-bg);
    color: var(--text-main);
    font-size: 1.1rem;
    text-align: center;
    outline: none;
    transition: var(--transition-smooth);
}
.practice-input:focus {
    border-color: var(--accent);
    box-shadow: 0 0 0 4px var(--accent-subtle);
}
.practice-input.correct {
    border-color: var(--success);
    box-shadow: 0 0 0 4px var(--success-subtle);
}
.practice-input.wrong {
    border-color: var(--danger);
    box-shadow: 0 0 0 4px var(--danger-subtle);
}

.practice-feedback {
    text-align: center;
    padding: 12px;
    border-radius: 12px;
    margin-bottom: 15px;
    font-size: 1rem;
    font-weight: 600;
    display: none;
}
.practice-feedback.show {
    display: block;
}
.practice-feedback.correct {
    background: var(--success-subtle);
    color: var(--success);
}
.practice-feedback.wrong {
    background: var(--danger-subtle);
    color: var(--danger);
}

.practice-actions {
    display: flex;
    gap: 12px;
    justify-content: center;
}

.practice-btn {
    padding: 12px 28px;
    border-radius: 12px;
    border: none;
    font-size: 0.95rem;
    font-weight: 600;
    cursor: pointer;
    transition: var(--transition-smooth);
}
.practice-btn:hover {
    transform: translateY(-2px);
}
.practice-btn-primary {
    background: var(--accent);
    color: white;
    box-shadow: 0 5px 15px var(--accent-glow);
}
.practice-btn-secondary {
    background: var(--card-bg);
    color: var(--text-muted);
    border: 1px solid var(--border-light);
}

/* Practice result summary */
.practice-result {
    text-align: center;
    padding: 30px;
}
.practice-result-score {
    font-size: 4rem;
    font-weight: 900;
    background: linear-gradient(135deg, var(--accent), #a78bfa);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    margin-bottom: 10px;
}
.practice-result-text {
    font-size: 1.2rem;
    color: var(--text-muted);
    margin-bottom: 20px;
}
.practice-result-details {
    display: flex;
    justify-content: center;
    gap: 30px;
    margin-bottom: 25px;
}
.practice-result-detail {
    text-align: center;
}
.practice-result-detail .detail-value {
    font-size: 1.5rem;
    font-weight: 700;
    display: block;
}
.practice-result-detail .detail-label {
    font-size: 0.85rem;
    color: var(--text-muted);
}
.practice-result-detail.correct .detail-value { color: var(--success); }
.practice-result-detail.wrong .detail-value { color: var(--danger); }
.practice-result-detail.total .detail-value { color: #a5b4fc; }


/* ========================================
   Navigation Tabs
   ======================================== */
.nav-tabs {
    display: flex;
    gap: 4px;
    margin-bottom: 20px;
    background: var(--glass);
    padding: 5px;
    border-radius: 14px;
    border: 1px solid var(--border-subtle);
    backdrop-filter: blur(15px);
}

.nav-tab {
    flex: 1;
    padding: 10px 16px;
    border: none;
    border-radius: 10px;
    background: transparent;
    color: var(--text-muted);
    font-size: 0.9rem;
    font-weight: 600;
    cursor: pointer;
    transition: var(--transition-smooth);
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 6px;
}
.nav-tab:hover {
    color: var(--text-main);
    background: var(--accent-subtle);
}
.nav-tab.active {
    background: var(--accent);
    color: white;
    box-shadow: 0 4px 12px var(--accent-glow);
}

/* ========================================
   Dashboard Cards
   ======================================== */
.dash-card {
    background: var(--glass);
    border-radius: 16px;
    padding: 20px;
    border: 1px solid var(--border-subtle);
    backdrop-filter: blur(15px);
    transition: var(--transition-smooth);
    text-align: center;
}
.dash-card:hover {
    transform: translateY(-3px);
    box-shadow: 0 8px 25px rgba(0, 0, 0, 0.2);
}

.dash-card-icon {
    font-size: 1.8rem;
    margin-bottom: 10px;
}

.dash-card-value {
    font-size: 2rem;
    font-weight: 900;
    color: var(--text-main);
    margin-bottom: 4px;
    letter-spacing: -0.5px;
}

.dash-card-label {
    font-size: 0.9rem;
    color: var(--text-muted);
    font-weight: 600;
}

.dash-card-sub {
    font-size: 0.75rem;
    color: var(--text-dim);
    margin-top: 4px;
}

.dash-mini-card {
    background: var(--card-bg);
    padding: 15px;
    border-radius: 12px;
    border: 1px solid var(--border-subtle);
    text-align: center;
}

.dash-mini-value {
    font-size: 1.5rem;
    font-weight: 800;
    color: #a5b4fc;
}

.dash-mini-label {
    font-size: 0.8rem;
    color: var(--text-muted);
    margin-top: 4px;
}

.dash-section {
    background: var(--glass);
    border-radius: 18px;
    padding: 20px;
    margin-bottom: 20px;
    border: 1px solid var(--border-subtle);
    backdrop-filter: blur(15px);
}

.dash-section-title {
    font-size: 1.05rem;
    font-weight: 700;
    color: var(--text-main);
    margin-bottom: 15px;
    padding-bottom: 10px;
    border-bottom: 1px solid var(--border-subtle);
}

/* Dashboard progress bars */
.dash-progress-container {
    margin-bottom: 10px;
}

.dash-progress-bar {
    height: 10px;
    background: var(--card-bg);
    border-radius: 10px;
    overflow: hidden;
    margin-bottom: 6px;
}

.dash-progress-fill {
    height: 100%;
    background: linear-gradient(90deg, var(--accent), #a78bfa);
    border-radius: 10px;
    transition: width 1s ease;
    position: relative;
}

.dash-progress-fill::after {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: linear-gradient(90deg, transparent, rgba(255,255,255,0.2), transparent);
    animation: shimmer 2s infinite;
}

@keyframes shimmer {
    0% { transform: translateX(-100%); }
    100% { transform: translateX(100%); }
}

.dash-progress-labels {
    display: flex;
    justify-content: space-between;
    font-size: 0.8rem;
    color: var(--text-dim);
}

/* Dashboard history list */
.dash-history-list {
    max-height: 250px;
    overflow-y: auto;
}

.dash-history-item {
    display: flex;
    align-items: center;
    padding: 10px 12px;
    border-bottom: 1px solid var(--border-subtle);
    font-size: 0.85rem;
    transition: var(--transition-smooth);
}
.dash-history-item:hover {
    background: var(--accent-subtle);
}
.dash-history-item:last-child {
    border-bottom: none;
}

.dash-history-date {
    flex: 1;
    color: var(--text-muted);
}
.dash-history-type {
    padding: 3px 8px;
    background: var(--accent-subtle);
    color: #a5b4fc;
    border-radius: 6px;
    font-size: 0.75rem;
    margin: 0 10px;
}
.dash-history-score {
    font-weight: 700;
    font-size: 0.9rem;
    min-width: 80px;
    text-align: right;
}

/* Dashboard words grid */
.dash-words-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(200px, 1fr));
    gap: 8px;
    max-height: 300px;
    overflow-y: auto;
}

.dash-word-chip {
    display: flex;
    align-items: center;
    gap: 8px;
    padding: 8px 12px;
    background: var(--card-bg);
    border-radius: 10px;
    border: 1px solid var(--border-subtle);
    font-size: 0.85rem;
    transition: var(--transition-smooth);
}
.dash-word-chip:hover {
    border-color: var(--accent);
    transform: translateY(-1px);
}

.dash-word-idx {
    color: var(--text-dim);
    font-size: 0.75rem;
    min-width: 18px;
}

.dash-word-indo {
    color: #a5b4fc;
    font-weight: 600;
}

.dash-word-zh {
    color: var(--text-muted);
    font-size: 0.8rem;
}


/* ========================================
   v1.2 Navigation Tabs
   ======================================== */
.nav-tabs {
    display: flex;
    gap: 4px;
    margin-bottom: 20px;
    background: var(--glass);
    padding: 5px;
    border-radius: 14px;
    border: 1px solid var(--border-subtle);
    backdrop-filter: blur(15px);
}
.nav-tab {
    flex: 1;
    padding: 10px 16px;
    border: none;
    border-radius: 10px;
    background: transparent;
    color: var(--text-muted);
    font-size: 0.9rem;
    font-weight: 600;
    cursor: pointer;
    transition: var(--transition-smooth);
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 6px;
}
.nav-tab:hover { color: var(--text-main); background: var(--accent-subtle); }
.nav-tab.active {
    background: var(--accent);
    color: white;
    box-shadow: 0 4px 12px var(--accent-glow);
}

/* ========================================
   v1.2 Theme Toggle Button
   ======================================== */
.theme-toggle {
    position: fixed;
    bottom: 20px;
    right: 20px;
    width: 45px;
    height: 45px;
    border-radius: 50%;
    background: var(--glass);
    border: 1px solid var(--border-subtle);
    color: var(--text-muted);
    font-size: 1.1rem;
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    z-index: 1000;
    transition: var(--transition-smooth);
    backdrop-filter: blur(15px);
}
.theme-toggle:hover {
    background: var(--accent);
    color: white;
    transform: scale(1.1);
}

/* ========================================
   v1.2 Practice Mode
   ======================================== */
.practice-container {
    margin: 0 auto;
}
.practice-type-selector {
    display: flex;
    gap: 8px;
    flex-wrap: wrap;
}
.practice-type-btn {
    flex: 1;
    min-width: 100px;
    padding: 12px 16px;
    border-radius: 10px;
    border: 1px solid var(--border-subtle);
    background: var(--card-bg);
    color: var(--text-muted);
    font-size: 0.9rem;
    font-weight: 600;
    cursor: pointer;
    transition: var(--transition-smooth);
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 6px;
}
.practice-type-btn:hover { border-color: var(--accent); color: var(--text-main); }
.practice-type-btn.active {
    background: var(--accent-subtle);
    border-color: var(--accent);
    color: #a5b4fc;
}
.practice-start-btn {
    background: var(--accent);
    color: white;
    border: none;
    padding: 12px 24px;
    border-radius: 10px;
    cursor: pointer;
    font-weight: 700;
    font-size: 1rem;
    transition: var(--transition-smooth);
}
.practice-start-btn:hover { transform: translateY(-2px); box-shadow: 0 4px 12px var(--accent-glow); }
.practice-btn-sec {
    background: var(--card-bg);
    color: var(--text-muted);
    border: 1px solid var(--border-subtle);
    padding: 12px 24px;
    border-radius: 10px;
    cursor: pointer;
    font-weight: 600;
    transition: var(--transition-smooth);
}
.practice-btn-sec:hover { border-color: var(--text-muted); color: var(--text-main); }
.practice-score-bar {
    display: flex;
    gap: 15px;
    margin-bottom: 20px;
    justify-content: center;
}
.practice-score-item {
    background: var(--card-bg);
    padding: 8px 16px;
    border-radius: 10px;
    border: 1px solid var(--border-subtle);
    font-size: 0.85rem;
    color: var(--text-muted);
    text-align: center;
}
.practice-score-item .score-val {
    font-size: 1.2rem;
    font-weight: 800;
    color: #a5b4fc;
    display: block;
}
.practice-question-box {
    background: var(--glass);
    padding: 25px;
    border-radius: 18px;
    border: 1px solid var(--border-subtle);
    text-align: center;
    margin-bottom: 20px;
}
.practice-options {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 10px;
    margin-bottom: 15px;
}
.practice-option {
    padding: 14px 18px;
    background: var(--card-bg);
    border: 2px solid var(--border-subtle);
    border-radius: 12px;
    color: var(--text-main);
    font-size: 0.95rem;
    font-weight: 600;
    cursor: pointer;
    transition: var(--transition-smooth);
    text-align: center;
}
.practice-option:hover:not(.disabled) {
    border-color: var(--accent);
    transform: translateY(-2px);
}
.practice-option.correct {
    background: rgba(16,185,129,0.15);
    border-color: #10b981;
    color: #34d399;
}
.practice-option.wrong {
    background: rgba(248,113,113,0.15);
    border-color: #ef4444;
    color: #f87171;
}
.practice-option.disabled { pointer-events: none; opacity: 0.7; }
.practice-input.correct { border-color: #10b981 !important; outline: none; }
.practice-input.wrong { border-color: #ef4444 !important; outline: none; }
.practice-feedback {
    display: none;
    padding: 12px 18px;
    border-radius: 10px;
    text-align: center;
    font-weight: 700;
    font-size: 0.95rem;
    margin-bottom: 10px;
}
.practice-feedback.show { display: block; }
.practice-feedback.correct { background: rgba(16,185,129,0.1); color: #34d399; border: 1px solid rgba(16,185,129,0.2); }
.practice-feedback.wrong { background: rgba(248,113,113,0.1); color: #f87171; border: 1px solid rgba(248,113,113,0.2); }

/* ========================================
   v1.2 Dashboard
   ======================================== */
.dash-card {
    background: var(--glass);
    border-radius: 16px;
    padding: 20px;
    border: 1px solid var(--border-subtle);
    backdrop-filter: blur(15px);
    transition: var(--transition-smooth);
    text-align: center;
}
.dash-card:hover { transform: translateY(-3px); box-shadow: 0 8px 25px rgba(0,0,0,0.2); }
.dash-card-value {
    font-size: 2rem;
    font-weight: 900;
    color: var(--text-main);
    margin-bottom: 4px;
}
.dash-card-label {
    font-size: 0.9rem;
    color: var(--text-muted);
    font-weight: 600;
}
.dash-card-sub { font-size: 0.75rem; color: var(--text-dim); margin-top: 4px; }
.dash-mini-card {
    background: var(--card-bg);
    padding: 15px;
    border-radius: 12px;
    border: 1px solid var(--border-subtle);
    text-align: center;
}
.dash-mini-value { font-size: 1.5rem; font-weight: 800; color: #a5b4fc; }
.dash-mini-label { font-size: 0.8rem; color: var(--text-muted); margin-top: 4px; }
.dash-section {
    background: var(--glass);
    border-radius: 18px;
    padding: 20px;
    margin-bottom: 20px;
    border: 1px solid var(--border-subtle);
    backdrop-filter: blur(15px);
}
.dash-section-title {
    font-size: 1.05rem;
    font-weight: 700;
    color: var(--text-main);
    margin-bottom: 15px;
    padding-bottom: 10px;
    border-bottom: 1px solid var(--border-subtle);
}
.dash-progress-bar {
    height: 10px;
    background: var(--card-bg);
    border-radius: 10px;
    overflow: hidden;
    margin-bottom: 6px;
}
.dash-progress-fill {
    height: 100%;
    background: linear-gradient(90deg, var(--accent), #a78bfa);
    border-radius: 10px;
    transition: width 1s ease;
    position: relative;
}
.dash-progress-fill::after {
    content: '';
    position: absolute;
    top: 0; left: 0; right: 0; bottom: 0;
    background: linear-gradient(90deg, transparent, rgba(255,255,255,0.2), transparent);
    animation: shimmer 2s infinite;
}
@keyframes shimmer {
    0% { transform: translateX(-100%); }
    100% { transform: translateX(100%); }
}
.dash-progress-labels {
    display: flex;
    justify-content: space-between;
    font-size: 0.8rem;
    color: var(--text-dim);
}
.dash-history-list { max-height: 250px; overflow-y: auto; }
.dash-history-item {
    display: flex;
    align-items: center;
    padding: 10px 12px;
    border-bottom: 1px solid var(--border-subtle);
    font-size: 0.85rem;
}
.dash-history-item:hover { background: var(--accent-subtle); }
.dash-history-item:last-child { border-bottom: none; }
.dash-history-date { flex: 1; color: var(--text-muted); }
.dash-history-type { padding: 3px 8px; background: var(--accent-subtle); color: #a5b4fc; border-radius: 6px; font-size: 0.75rem; margin: 0 10px; }
.dash-history-score { font-weight: 700; font-size: 0.9rem; min-width: 80px; text-align: right; }
.dash-words-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(200px, 1fr));
    gap: 8px;
    max-height: 300px;
    overflow-y: auto;
}
.dash-word-chip {
    display: flex;
    align-items: center;
    gap: 8px;
    padding: 8px 12px;
    background: var(--card-bg);
    border-radius: 10px;
    border: 1px solid var(--border-subtle);
    font-size: 0.85rem;
}
.dash-word-chip:hover { border-color: var(--accent); }
.dash-word-idx { color: var(--text-dim); font-size: 0.75rem; min-width: 18px; }
.dash-word-indo { color: #a5b4fc; font-weight: 600; }
.dash-word-zh { color: var(--text-muted); font-size: 0.8rem; }

/* ========================================
   Responsive
   ======================================== */
@media (max-width: 1200px) {
    .nav-tabs {
        margin-bottom: 15px;
    }
    .nav-tab {
        padding: 8px 12px;
        font-size: 0.85rem;
    }
    .main-container {
        margin-left: 0;
        padding: 20px;
    }
    .sidebar {
        z-index: 2000;
    }
    .indo-box {
        font-size: 4rem;
    }
    .zh-box {
        font-size: 2rem;
    }
    .practice-question-word {
        font-size: 2.2rem;
    }
    .practice-options {
        grid-template-columns: 1fr;
    }
}


/* ========================================
   大屏适配 - Desktop Optimization (≥1200px)
   ======================================== */

/* 页面内容撑满容器 */
#page-learn,
#page-practice,
#page-dashboard {
    width: 100%;
    flex: 1;
    display: flex;
    flex-direction: column;
}

/* 学习页面：进度和推荐卡片行 */
.learn-cards-row {
    display: flex;
    gap: 20px;
    margin-bottom: 20px;
    flex-wrap: wrap;
}
.learn-cards-row > div {
    flex: 1;
    min-width: 280px;
}

/* 学习卡片最大宽度 */
.study-card {
    min-height: 350px;
    flex: 1;
}

/* 统计页面卡片 - 4列横排 */
.dash-stats-grid {
    display: grid !important;
    grid-template-columns: repeat(4, 1fr) !important;
    gap: 15px !important;
    margin-bottom: 25px;
}

/* 统计页面的练习历史小卡片 - 横排 */
.dash-mini-grid {
    display: grid !important;
    grid-template-columns: repeat(2, 1fr) !important;
    gap: 12px !important;
    margin-bottom: 15px;
}

/* 练习页面容器限制宽度 */
.practice-container {
    width: 100%;
    flex: 1;
    display: flex;
    flex-direction: column;
}

/* 练习设置卡片底部填满 */
.practice-settings-card {
    margin-top: auto;
}

@media (max-width: 768px) {
    .nav-tabs {
        flex-wrap: nowrap;
        overflow-x: auto;
        gap: 2px;
        padding: 4px;
        -webkit-overflow-scrolling: touch;
    }
    .nav-tab {
        padding: 8px 14px;
        font-size: 0.8rem;
        white-space: nowrap;
    }
    .dash-card-value {
        font-size: 1.5rem;
    }
    .dash-words-grid {
        grid-template-columns: 1fr;
    }
    .main-container {
        padding: 15px;
    }
    .main-title {
        font-size: 2rem;
    }
    .indo-box {
        font-size: 3rem;
    }
    .zh-box {
        font-size: 1.5rem;
        letter-spacing: 2px;
    }
    .study-card {
        border-radius: 30px;
        min-height: 300px;
        padding: 30px 20px;
    }
    .top-meta {
        top: 20px;
        left: 25px;
        right: 25px;
    }
    .nav-row {
        gap: 20px;
        margin-top: 30px;
    }
    .circle-btn {
        width: 60px;
        height: 60px;
        font-size: 1.5rem;
    }
    .play-btn {
        width: 80px;
        height: 80px;
    }
    .control-panel {
        padding: 20px 25px;
        border-radius: 20px;
    }
    .stats-bar {
        padding: 10px;
    }
    .stat-item {
        font-size: 12px;
        padding: 6px 10px;
    }
    .theme-toggle {
        bottom: 15px;
        right: 15px;
        width: 40px;
        height: 40px;
        font-size: 1rem;
    }
    .practice-container {
        padding: 20px;
    }
    .practice-question-word {
        font-size: 2rem;
    }
    .practice-type-selector {
        flex-wrap: wrap;
    }
    .top-info-bar {
        flex-wrap: wrap;
        gap: 8px;
    }
}