/* ============================================================
    CSS 变量
    ============================================================ */
:root {
    --bg: #0b0918;
    --bg-card: rgba(255, 255, 255, 0.04);
    --primary: #7c4dff;
    --primary-light: #b388ff;
    --accent: #00e5ff;
    --accent-glow: rgba(0, 229, 255, 0.5);
    --purple: #d500f9;
    --text: #ffffff;
    --text-secondary: rgba(255, 255, 255, 0.72);
    --text-muted: rgba(255, 255, 255, 0.75);
    --border: rgba(255, 255, 255, 0.06);
    --border-glow: rgba(255, 255, 255, 0.12);
    --radius: 20px;
    --radius-sm: 12px;
    --radius-lg: 28px;
    --transition: 0.35s cubic-bezier(0.4, 0, 0.2, 1);
    --shadow-card: 0 8px 40px rgba(0, 0, 0, 0.5);
    --shadow-glow: 0 0 80px rgba(124, 77, 255, 0.25);
    --gradient-accent: linear-gradient(135deg, #7c4dff, #d500f9);
    --gradient-text: linear-gradient(90deg, #b388ff, #7c4dff, #00e5ff);
}

/* ============================================================
    全局重置
    ============================================================ */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}
html {
    scroll-behavior: smooth;
    font-size: 16px;
}
body {
    font-family: 'Inter', 'Segoe UI', 'PingFang SC', 'Microsoft YaHei', system-ui, sans-serif;
    background: var(--bg);
    color: var(--text);
    line-height: 1.7;
    overflow-x: hidden;
    -webkit-font-smoothing: antialiased;
    min-height: 100vh;
    display: flex;
    flex-direction: column;
}

/* ============================================================
    粒子背景
    ============================================================ */
#particleCanvas {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    z-index: 0;
    pointer-events: none;
}

/* ============================================================
    环境光晕
    ============================================================ */
.ambient-glow {
    position: fixed;
    border-radius: 50%;
    filter: blur(120px);
    opacity: 0.3;
    pointer-events: none;
    z-index: 0;
    animation: ambientFloat 12s ease-in-out infinite;
}
.ambient-glow.glow-1 {
    width: 500px;
    height: 500px;
    background: var(--primary);
    top: -15%;
    left: -15%;
    animation-delay: 0s;
}
.ambient-glow.glow-2 {
    width: 400px;
    height: 400px;
    background: var(--purple);
    bottom: -20%;
    right: -15%;
    animation-delay: -5s;
    animation-duration: 15s;
}
.ambient-glow.glow-3 {
    width: 300px;
    height: 300px;
    background: var(--accent);
    top: 50%;
    left: 55%;
    animation-delay: -9s;
    animation-duration: 18s;
    opacity: 0.15;
}

@keyframes ambientFloat {
    0%, 100% { transform: translate(0, 0) scale(1); }
    25% { transform: translate(40px, -50px) scale(1.15); }
    50% { transform: translate(-30px, 30px) scale(0.9); }
    75% { transform: translate(-50px, -20px) scale(1.1); }
}

/* ============================================================
    主容器
    ============================================================ */
.main-container {
    position: relative;
    z-index: 1;
    flex: 1;
    display: flex;
    flex-direction: column;
}

/* ===== 导航栏（统一） ===== */
.navbar {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    z-index: 1000;
    background: rgba(11, 9, 24, 0.75);
    backdrop-filter: blur(16px);
    -webkit-backdrop-filter: blur(16px);
    border-bottom: 1px solid var(--border);
    padding: 0 20px;
    display: flex;
    align-items: center;
    justify-content: space-between;
    height: 60px;
}

.navbar .brand {
    display: flex;
    align-items: center;
    gap: 8px;
    font-weight: 700;
    font-size: 1.2rem;
    color: #fff;
    text-decoration: none;
    flex-shrink: 0;
}

.navbar .brand .dot {
    width: 10px;
    height: 10px;
    border-radius: 50%;
    background: var(--accent);
    box-shadow: 0 0 16px var(--accent-glow);
    animation: logoPulse 2s ease-in-out infinite;
}

/* 桌面导航链接 */
.nav-links {
    display: flex;
    gap: 8px;
    list-style: none;
    align-items: center;
    margin: 0;
    padding: 0;
}

.nav-links a {
    color: var(--text-secondary);
    text-decoration: none;
    font-size: 0.9rem;
    font-weight: 500;
    padding: 6px 14px;
    border-radius: 20px;
    transition: var(--transition);
    white-space: nowrap;
}

.nav-links a:hover {
    color: #fff;
    background: rgba(255, 255, 255, 0.05);
}

.nav-links a.active {
    color: #fff;
    background: rgba(124, 77, 255, 0.15);
    border: 1px solid rgba(124, 77, 255, 0.3);
}

/* 汉堡按钮（桌面隐藏） */
.hamburger {
    display: none;
    flex-direction: column;
    gap: 5px;
    background: none;
    border: none;
    cursor: pointer;
    padding: 4px;
    z-index: 1001;
}

.hamburger span {
    display: block;
    width: 25px;
    height: 2.5px;
    background: #fff;
    border-radius: 2px;
    transition: var(--transition);
    transform-origin: center;
}

/* 移动端导航菜单（初始隐藏） */
.mobile-menu {
    display: none;
    position: fixed;
    top: 60px;
    left: 0;
    width: 100%;
    background: rgba(11, 9, 24, 0.95);
    backdrop-filter: blur(16px);
    -webkit-backdrop-filter: blur(16px);
    border-bottom: 1px solid var(--border);
    padding: 16px 20px;
    flex-direction: column;
    gap: 12px;
    z-index: 999;
    animation: slideDown 0.3s ease forwards;
}

.mobile-menu a {
    color: var(--text-secondary);
    text-decoration: none;
    font-size: 1rem;
    font-weight: 500;
    padding: 8px 0;
    border-bottom: 1px solid var(--border);
    transition: var(--transition);
}

.mobile-menu a:last-child {
    border-bottom: none;
}

.mobile-menu a:hover,
.mobile-menu a.active {
    color: #fff;
}

.mobile-menu.open {
    display: flex;
}

@keyframes slideDown {
    from { opacity: 0; transform: translateY(-10px); }
    to { opacity: 1; transform: translateY(0); }
}

/* 亮色主题适配 */
@media (prefers-color-scheme: light) {
    .navbar {
        background: rgba(255, 255, 255, 0.85);
        border-color: var(--border);
    }
    .navbar .brand {
        color: var(--text);
    }
    .nav-links a {
        color: var(--text-secondary);
    }
    .nav-links a:hover {
        color: var(--text);
        background: rgba(124, 77, 255, 0.04);
    }
    .nav-links a.active {
        color: #fff;
        background: var(--gradient-accent);
    }
    .hamburger span {
        background: var(--text);
    }
    .mobile-menu {
        background: rgba(255, 255, 255, 0.95);
    }
    .mobile-menu a {
        color: var(--text-secondary);
        border-color: var(--border);
    }
    .mobile-menu a:hover,
    .mobile-menu a.active {
        color: var(--text);
    }
}

/* 响应式 */
@media (max-width: 768px) {
    .nav-links {
        display: none;
    }
    .hamburger {
        display: flex;
    }
    .navbar {
        padding: 0 16px;
        height: 56px;
    }
    .navbar .brand {
        font-size: 1rem;
    }
}

/* ============================================================
    页面标题
    ============================================================ */
.page-header {
    text-align: center;
    padding: 100px 24px 20px;
}
.page-header .badge {
    display: inline-block;
    font-size: 0.75rem;
    font-weight: 700;
    text-transform: uppercase;
    letter-spacing: 2px;
    color: var(--primary-light);
    background: rgba(124, 77, 255, 0.1);
    padding: 6px 18px;
    border-radius: 20px;
    margin-bottom: 12px;
}
.page-header h1 {
    font-size: clamp(2rem, 4.5vw, 3rem);
    font-weight: 800;
    letter-spacing: -0.8px;
    color: #fff;
}
.page-header h1 .highlight {
    background: var(--gradient-text);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
    color: transparent;
}
.page-header p {
    color: var(--text-secondary);
    max-width: 550px;
    margin: 8px auto 0;
    font-size: 1rem;
}

/* ============================================================
    单元切换 Tab
    ============================================================ */
.unit-tabs {
    display: flex;
    flex-wrap: wrap;
    justify-content: center;
    gap: 8px;
    padding: 16px 24px 8px;
    max-width: 1100px;
    margin: 0 auto;
    width: 100%;
}
.unit-tabs .tab-btn {
    padding: 8px 12px;
    border-radius: 30px;
    border: 1px solid var(--border);
    background: transparent;
    color: var(--text-secondary);
    font-size: 0.82rem;
    font-weight: 500;
    cursor: pointer;
    transition: var(--transition);
    font-family: inherit;
    white-space: nowrap;
}
.unit-tabs .tab-btn:hover {
    border-color: var(--border-glow);
    color: #fff;
    background: rgba(255, 255, 255, 0.04);
}
.unit-tabs .tab-btn.active {
    background: var(--gradient-accent);
    color: #fff;
    border-color: transparent;
    box-shadow: 0 4px 20px rgba(124, 77, 255, 0.3);
}

/* ============================================================
    知识清单内容区
    ============================================================ */
.content-area {
    max-width: 1100px;
    margin: 0 auto;
    padding: 20px 24px 60px;
    width: 100%;
    flex: 1;
}

.unit-content {
    display: none;
    animation: fadeInUp 0.4s ease forwards;
}
.unit-content.active {
    display: block;
}

@keyframes fadeInUp {
    from { opacity: 0; transform: translateY(16px); }
    to { opacity: 1; transform: translateY(0); }
}

/* ============================================================
    课题卡片
    ============================================================ */
.topic-card {
    background: var(--bg-card);
    border: 1px solid var(--border);
    border-radius: var(--radius);
    padding: 28px 30px;
    margin-bottom: 24px;
    backdrop-filter: blur(8px);
    -webkit-backdrop-filter: blur(8px);
    box-shadow: var(--shadow-card);
    transition: var(--transition);
}
.topic-card:hover {
    border-color: var(--border-glow);
    box-shadow: var(--shadow-card), var(--shadow-glow);
}
.topic-card .topic-title {
    font-size: 1.3rem;
    font-weight: 700;
    color: #fff;
    margin-bottom: 6px;
    display: flex;
    align-items: center;
    gap: 12px;
}
.topic-card .topic-title .num {
    color: var(--primary-light);
    font-size: 1rem;
    font-weight: 600;
    background: rgba(124, 77, 255, 0.15);
    padding: 2px 12px;
    border-radius: 20px;
}
.topic-card .topic-sub {
    color: var(--text-muted);
    font-size: 0.85rem;
    margin-bottom: 16px;
    border-bottom: 1px solid var(--border);
    padding-bottom: 12px;
}

.topic-card .knowledge-item {
    padding: 10px 0;
    border-bottom: 1px solid rgba(255, 255, 255, 0.04);
}
.topic-card .knowledge-item:last-child {
    border-bottom: none;
}
.topic-card .knowledge-item .label {
    display: inline-block;
    font-size: 0.9rem;          /* 原来是 0.7rem，增大到 0.9rem */
    font-weight: 700;           /* 可加粗，原没有明确设置，可添加 */
    padding: 4px 14px;          /* 原来可能是 2px 12px，适当增加内边距 */
    text-transform: uppercase;
    letter-spacing: 0.5px;
    color: var(--accent);
    background: rgba(0, 229, 255, 0.08);
    padding: 2px 12px;
    border-radius: 12px;
    margin-right: 8px;
}
.topic-card .knowledge-item .label.important {
    color: #ffa657;
    background: rgba(255, 166, 87, 0.12);
}
.topic-card .knowledge-item .label.formula {
    color: #a5d6ff;
    background: rgba(165, 214, 255, 0.1);
}
.topic-card .knowledge-item .label.experiment {
    color: #69db7c;
    background: rgba(105, 219, 124, 0.1);
}
.topic-card .knowledge-item p {
    color: var(--text-secondary);
    font-size: 0.95rem;
    line-height: 1.7;
    margin-top: 4px;
    padding-left: 4px;
}
.topic-card .knowledge-item p strong {
    color: #fff;
    font-weight: 600;
}
.topic-card .knowledge-item p .highlight-text {
    color: var(--primary-light);
}
.topic-card .knowledge-item p .eq-text {
    color: #a5d6ff;
    font-family: 'Times New Roman', serif;
    font-size: 1.05rem;
}
.topic-card .knowledge-item ul {
    list-style: none;
    padding-left: 8px;
    margin-top: 4px;
}
.topic-card .knowledge-item ul li {
    color: var(--text-secondary);
    font-size: 0.93rem;
    line-height: 1.7;
    padding: 2px 0 2px 20px;
    position: relative;
}
.topic-card .knowledge-item ul li::before {
    content: '›';
    position: absolute;
    left: 4px;
    color: var(--primary-light);
    font-weight: 700;
}
/* 修复 ul li 内部 highlight-text 被覆盖的问题 */
.topic-card .knowledge-item ul li .highlight-text {
    color: var(--primary-light) !important;
}

/* ============================================================
    页脚
    ============================================================ */
.footer {
    text-align: center;
    padding: 24px 24px 32px;
    color: var(--text-muted);
    font-size: 0.8rem;
    border-top: 1px solid var(--border);
    position: relative;
    z-index: 1;
    background: rgba(11, 9, 24, 0.5);
    backdrop-filter: blur(4px);
    -webkit-backdrop-filter: blur(4px);
}
.footer a {
    color: var(--primary-light);
    text-decoration: none;
    transition: var(--transition);
}
.footer a:hover { color: #fff; }

/* ============================================================
    响应式
    ============================================================ */
@media (max-width: 768px) {
    .top-bar {
        padding: 12px 16px;
        flex-wrap: wrap;
        gap: 8px;
    }
    .top-bar .brand {
        font-size: 0.95rem;
        gap: 6px;
    }
    .top-bar .brand .dot {
        width: 8px;
        height: 8px;
    }
    .top-bar .nav-links {
        gap: 6px;
        flex-wrap: wrap;
    }
    .top-bar .nav-links a {
        font-size: 0.75rem;
        padding: 4px 10px;
    }
    .top-bar .back-home {
        font-size: 0.75rem;
        padding: 4px 10px;
    }
    .page-header {
        padding: 80px 16px 12px;
    }
    .page-header h1 {
        font-size: 1.6rem;
    }
    .unit-tabs {
        padding: 12px 12px 4px;
        gap: 6px;
    }
    .unit-tabs .tab-btn {
        font-size: 0.7rem;
        padding: 5px 12px;
    }
    .content-area {
        padding: 12px 14px 40px;
    }
    .topic-card {
        padding: 20px 18px;
    }
    .topic-card .topic-title {
        font-size: 1.1rem;
        flex-wrap: wrap;
    }
    .topic-card .knowledge-item p {
        font-size: 0.88rem;
    }
    .topic-card .knowledge-item ul li {
        font-size: 0.86rem;
    }
}

@media (max-width: 480px) {
    .top-bar {
        padding: 8px 12px;
    }
    .top-bar .brand {
        font-size: 0.8rem;
    }
    .top-bar .nav-links a {
        font-size: 0.65rem;
        padding: 3px 7px;
    }
    .top-bar .back-home {
        font-size: 0.65rem;
        padding: 3px 8px;
    }
    .unit-tabs .tab-btn {
        font-size: 0.6rem;
        padding: 4px 8px;
    }
    .topic-card {
        padding: 16px 14px;
    }
    .topic-card .topic-title {
        font-size: 0.95rem;
    }
    .topic-card .knowledge-item .label {
        font-size: 0.6rem;
        padding: 1px 8px;
    }
    .topic-card .knowledge-item p {
        font-size: 0.82rem;
    }
    .topic-card .knowledge-item ul li {
        font-size: 0.8rem;
        padding: 1px 0 1px 16px;
    }
}

@media (hover: none) {
    .topic-card:hover {
        border-color: var(--border) !important;
        box-shadow: var(--shadow-card) !important;
    }
    .unit-tabs .tab-btn:hover {
        background: transparent !important;
        color: var(--text-secondary) !important;
        border-color: var(--border) !important;
    }
}
/* ============================================================
亮色主题（适配系统浅色模式）
============================================================ */
@media (prefers-color-scheme: light) {
    :root {
        /* 基础背景与文字 */
        --bg: #f5f2ff;
        --bg-card: rgba(255, 255, 255, 0.85);
        --text: #1a1a2e;
        --text-secondary: #3d3d5c;
        --text-muted: #6b6b8a;

        /* 边框与阴影 */
        --border: rgba(124, 77, 255, 0.15);
        --border-glow: rgba(124, 77, 255, 0.25);
        --shadow-card: 0 8px 32px rgba(124, 77, 255, 0.10);
        --shadow-glow: 0 0 60px rgba(124, 77, 255, 0.08);

        /* 高亮颜色（适配亮色，紫色适当加深） */
        --primary-light: #6a3de8;
        --primary: #7c4dff;
        --accent: #0088cc;
        --accent-glow: rgba(0, 136, 204, 0.4);
        --purple: #c84dff;
        --purple-glow: rgba(200, 77, 255, 0.3);

        /* 渐变（保持紫色调但微调） */
        --gradient-text: linear-gradient(90deg, #6a3de8, #7c4dff, #0088cc);
        --gradient-accent: linear-gradient(135deg, #6a3de8, #c84dff);
    }

    /* ====== 背景光晕（亮色下淡化或隐藏） ====== */
    .ambient-glow {
        opacity: 0.08 !important;
    }

    /* ====== 粒子背景（亮色下变淡） ====== */
    #particleCanvas {
        opacity: 0.5;
    }

    /* ====== 导航栏 ====== */
    .navbar {
        background: rgba(255, 255, 255, 0.75);
        backdrop-filter: blur(20px);
        -webkit-backdrop-filter: blur(20px);
        border-color: var(--border);
        box-shadow: 0 4px 30px rgba(124, 77, 255, 0.08);
    }
    .navbar:hover {
        border-color: var(--border-glow);
        box-shadow: 0 4px 40px rgba(124, 77, 255, 0.12);
    }
    .nav-logo {
        color: var(--text);
    }
    .top-bar .nav-links a,
    .top-bar .nav-links a.active {
        color: var(--text-secondary);
    }
    .top-bar .nav-links a:hover {
        color: var(--text) !important;          /* 亮色下 --text 为深色 */
        background: rgba(124, 77, 255, 0.06) !important;
    }

    /* ====== Hero ====== */
    .hero-badge {
        background: rgba(124, 77, 255, 0.08);
        border-color: rgba(124, 77, 255, 0.2);
        color: var(--primary-light);
    }
    .hero-subtitle {
        color: var(--text-secondary);
    }
    .btn-outline {
        color: var(--text);
        border-color: rgba(124, 77, 255, 0.3);
    }
    .btn-outline:hover {
        border-color: var(--primary-light);
        background: rgba(124, 77, 255, 0.04);
    }

    /* ====== 特性卡片 ====== */
    .feature-card {
        background: var(--bg-card);
        border-color: var(--border);
        box-shadow: var(--shadow-card);
    }
    .feature-card:hover {
        border-color: var(--border-glow);
        box-shadow: var(--shadow-card), var(--shadow-glow);
    }
    .feature-card h3 {
        color: var(--text);
    }
    .feature-card p {
        color: var(--text-secondary);
    }
    .feature-card .card-glow {
        opacity: 0 !important;
    }

    /* ====== 方程卡片 ====== */
    .equation-item {
        background: rgba(255, 255, 255, 0.7);
        border-color: var(--border);
    }
    .equation-item:hover {
        border-color: var(--primary-light);
        box-shadow: 0 8px 25px rgba(124, 77, 255, 0.08);
    }
    .equation-item .eq {
        color: var(--text);
    }
    .equation-item .eq-desc {
        color: var(--text-muted);
    }

    /* ====== 知识清单 ====== */
    .topic-card {
        background: var(--bg-card);
        border-color: var(--border);
        box-shadow: var(--shadow-card);
    }
    .topic-card:hover {
        border-color: var(--border-glow);
        box-shadow: var(--shadow-card), var(--shadow-glow);
    }
    .topic-card .topic-title {
        color: var(--text);
    }
    .topic-card .topic-title .num {
        background: rgba(124, 77, 255, 0.1);
        color: var(--primary-light);
    }
    .topic-card .topic-sub {
        color: var(--text-muted);
        border-bottom-color: var(--border);
    }
    .topic-card .knowledge-item {
        border-bottom-color: rgba(124, 77, 255, 0.06);
    }
    .topic-card .knowledge-item .label {
        color: var(--primary-light);
        background: rgba(124, 77, 255, 0.08);
    }
    .topic-card .knowledge-item .label.important {
        color: #c0392b;
        background: rgba(192, 57, 43, 0.08);
    }
    .topic-card .knowledge-item .label.formula {
        color: #0088cc;
        background: rgba(0, 136, 204, 0.08);
    }
    .topic-card .knowledge-item .label.experiment {
        color: #1a8a4a;
        background: rgba(26, 138, 74, 0.08);
    }
    .topic-card .knowledge-item p {
        color: var(--text-secondary);
    }
    .topic-card .knowledge-item p strong {
        color: var(--text);
    }
    .topic-card .knowledge-item p .highlight-text {
        color: var(--primary-light);
        font-weight: 600;
    }
    .topic-card .knowledge-item ul li {
        color: var(--text-secondary);
    }
    .topic-card .knowledge-item ul li::before {
        color: var(--primary-light);
    }
    .topic-card .knowledge-item ul li .highlight-text {
        color: var(--primary-light);
        font-weight: 600;
    }
    .topic-card .knowledge-item .eq-text {
        color: #0088cc;
    }

    /* ====== 对话气泡 ====== */
    .chat-bubble.user {
        background: rgba(124, 77, 255, 0.10);
        border-color: rgba(124, 77, 255, 0.25);
        color: var(--text);
    }
    .chat-bubble.ai {
        background: rgba(255, 255, 255, 0.8);
        border-color: var(--border);
        color: var(--text);
    }

    /* ====== CTA 区域 ====== */
    .cta-card {
        background: var(--bg-card);
        border-color: var(--border);
        box-shadow: var(--shadow-card);
    }
    .cta-card h2 {
        color: var(--text);
    }
    .cta-card p {
        color: var(--text-secondary);
    }

    /* ====== 统计区域 ====== */
    .stats-section {
        background: rgba(255, 255, 255, 0.4);
        border-top-color: var(--border);
        border-bottom-color: var(--border);
    }

    /* ====== 页脚 ====== */
    .footer {
        color: var(--text-muted);
        border-top-color: var(--border);
        background: rgba(255, 255, 255, 0.4);
    }
    .footer a {
        color: var(--primary-light);
    }
    .footer a:hover {
        color: var(--text);
    }
    .footer .footer-heart {
        color: #c84dff;
    }

    /* ====== 导航页（navigition） ====== */
    .top-bar {
        background: rgba(255, 255, 255, 0.75);
        border-bottom-color: var(--border);
    }
    .top-bar .brand {
        color: var(--text);
    }
    .top-bar .back-home {
        color: var(--text-secondary);
        border-color: var(--border);
    }
    .top-bar .back-home:hover {
        background: rgba(124, 77, 255, 0.04);
        border-color: var(--border-glow);
        color: var(--text);
    }
    .nav-card {
        background: var(--bg-card);
        border-color: var(--border);
        box-shadow: var(--shadow-card);
    }
    .nav-card:hover {
        border-color: var(--border-glow);
        box-shadow: var(--shadow-card), var(--shadow-glow);
    }
    .nav-card h3 {
        color: var(--text);
    }
    .nav-card p {
        color: var(--text-secondary);
    }
    .nav-card .arrow {
        color: var(--primary-light);
    }
    .nav-card:hover .arrow {
        color: var(--text);
    }
    .nav-card .card-glow {
        opacity: 0 !important;
    }

    /* ====== 单元 Tab 按钮 ====== */
    .unit-tabs .tab-btn {
        color: var(--text-secondary);
        border-color: var(--border);
    }
    .unit-tabs .tab-btn:hover {
        border-color: var(--border-glow);
        color: var(--text);
        background: rgba(124, 77, 255, 0.04);
    }
    .unit-tabs .tab-btn.active {
        background: var(--gradient-accent);
        color: #fff;
        border-color: transparent;
        box-shadow: 0 4px 20px rgba(124, 77, 255, 0.25);
    }

    /* ====== 页码标题 ====== */
    .page-header h1 {
        color: var(--text);
    }
    .page-header p {
        color: var(--text-secondary);
    }

    /* ====== 代码高亮 ====== */
    .code-showcase {
        background: rgba(255, 255, 255, 0.9);
        border-color: var(--border);
    }
    .code-header {
        background: rgba(240, 240, 255, 0.9);
        border-bottom-color: var(--border);
    }
    .code-body {
        color: #1a1a2e;
    }
    .code-body .comment {
        color: #6b6b8a;
    }
    .code-body .keyword {
        color: #c0392b;
    }
    .code-body .string {
        color: #0088cc;
    }
    .code-body .func {
        color: #6a3de8;
    }
    .code-body .number {
        color: #0088cc;
    }
    .code-body .type {
        color: #c84dff;
    }
}