/* ============================================
   孙琪翔个人网站 - 毛玻璃 × Apple 极简风格
   Glassmorphism + Apple Design Language
   ============================================ */

/* ---------- 基础重置 ---------- */
*, *::before, *::after {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

:root {
    /* 色彩体系 - 柔和渐变底色 */
    --bg-base: #f0f1f5;
    --blob-1: #a5b4fc;
    --blob-2: #f9a8d4;
    --blob-3: #6ee7b7;
    --blob-4: #fdba74;

    /* 毛玻璃卡片 - 保证文字可读 */
    --glass-bg: rgba(255, 255, 255, 0.55);
    --glass-bg-hover: rgba(255, 255, 255, 0.65);
    --glass-border: rgba(255, 255, 255, 0.6);
    --glass-shadow: 0 8px 32px rgba(31, 38, 135, 0.12);
    --glass-shadow-hover: 0 12px 40px rgba(31, 38, 135, 0.18);
    --glass-blur: 20px;

    /* 文字色 */
    --text-primary: #1d1d1f;
    --text-secondary: #6e6e73;
    --text-tertiary: #86868b;
    --text-on-accent: #ffffff;
    --text-shadow: none;

    /* 强调色 */
    --accent-primary: #6366f1;
    --accent-secondary: #ec4899;
    --accent-tertiary: #10b981;
    --accent-warm: #f59e0b;

    /* 渐变 */
    --gradient-hero: linear-gradient(135deg, #6366f1 0%, #ec4899 100%);
    --gradient-accent: linear-gradient(135deg, #818cf8 0%, #f472b6 100%);

    /* 圆角 */
    --radius-sm: 12px;
    --radius-md: 18px;
    --radius-lg: 24px;
    --radius-xl: 32px;

    /* 过渡 */
    --transition: all 0.4s cubic-bezier(0.25, 0.46, 0.45, 0.94);
    --transition-slow: all 0.6s cubic-bezier(0.25, 0.46, 0.45, 0.94);
}

html {
    scroll-behavior: smooth;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

body {
    font-family: 'Inter', 'Noto Sans SC', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
    background: var(--bg-base);
    color: var(--text-primary);
    line-height: 1.6;
    overflow-x: hidden;
    min-height: 100vh;
    position: relative;
}

/* ---------- 动态渐变背景 ---------- */
.bg-gradient {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    z-index: -1;
    overflow: hidden;
    background: var(--bg-base);
}

.bg-blob {
    position: absolute;
    border-radius: 50%;
    filter: blur(80px);
    opacity: 0.6;
    animation: float 20s ease-in-out infinite;
}

.blob-1 {
    width: 700px;
    height: 700px;
    background: var(--blob-1);
    top: -250px;
    left: -200px;
    animation-delay: 0s;
}

.blob-2 {
    width: 600px;
    height: 600px;
    background: var(--blob-2);
    top: 25%;
    right: -150px;
    animation-delay: -5s;
}

.blob-3 {
    width: 650px;
    height: 650px;
    background: var(--blob-3);
    bottom: -250px;
    left: 15%;
    animation-delay: -10s;
}

@keyframes float {
    0%, 100% { transform: translate(0, 0) scale(1); }
    33% { transform: translate(50px, -30px) scale(1.05); }
    66% { transform: translate(-30px, 40px) scale(0.95); }
}

/* ---------- 毛玻璃卡片基础 ---------- */
.glass-card {
    background: var(--glass-bg);
    backdrop-filter: blur(var(--glass-blur)) saturate(200%);
    -webkit-backdrop-filter: blur(var(--glass-blur)) saturate(200%);
    border: 1px solid var(--glass-border);
    border-radius: var(--radius-lg);
    box-shadow: var(--glass-shadow), inset 0 1px 0 rgba(255, 255, 255, 0.5);
    transition: var(--transition);
    position: relative;
    overflow: hidden;
}

.glass-card::after {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    border-radius: var(--radius-lg);
    background: url("data:image/svg+xml,%3Csvg viewBox='0 0 200 200' xmlns='http://www.w3.org/2000/svg'%3E%3Cfilter id='n'%3E%3CfeTurbulence type='fractalNoise' baseFrequency='0.9' numOctaves='3'/%3E%3C/filter%3E%3Crect width='100%25' height='100%25' filter='url(%23n)' opacity='0.03'/%3E%3C/svg%3E");
    pointer-events: none;
    opacity: 0.4;
    z-index: 0;
}

.glass-card > * {
    position: relative;
    z-index: 1;
}

.glass-card::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    height: 1px;
    background: linear-gradient(90deg, transparent, rgba(255,255,255,0.8), transparent);
}

.glass-card:hover {
    background: var(--glass-bg-hover);
    box-shadow: var(--glass-shadow-hover);
    transform: translateY(-4px);
}

.glass-card-inner {
    background: rgba(255, 255, 255, 0.4);
    backdrop-filter: blur(10px);
    -webkit-backdrop-filter: blur(10px);
    border: 1px solid rgba(255, 255, 255, 0.5);
    border-radius: var(--radius-md);
    padding: 1.25rem 1.5rem;
    transition: var(--transition);
}

.glass-card-inner:hover {
    background: rgba(255, 255, 255, 0.55);
    transform: translateX(6px);
}

/* ---------- 导航栏 ---------- */
.nav-glass {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    z-index: 1000;
    background: rgba(255, 255, 255, 0.6);
    backdrop-filter: blur(20px);
    -webkit-backdrop-filter: blur(20px);
    border-bottom: 1px solid rgba(255, 255, 255, 0.5);
    transition: var(--transition);
}

.nav-glass.scrolled {
    background: rgba(255, 255, 255, 0.75);
    box-shadow: 0 2px 20px rgba(0, 0, 0, 0.06);
}

.nav-inner {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0.75rem 2rem;
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 2rem;
}

.nav-logo {
    font-size: 1.25rem;
    font-weight: 600;
    color: var(--text-primary);
    text-decoration: none;
    letter-spacing: -0.02em;
}

.nav-links {
    display: flex;
    gap: 1.75rem;
    align-items: center;
}

.nav-links a {
    font-size: 0.9rem;
    color: var(--text-secondary);
    text-decoration: none;
    font-weight: 400;
    transition: var(--transition);
    position: relative;
}

.nav-links a::after {
    content: '';
    position: absolute;
    bottom: -4px;
    left: 0;
    width: 0;
    height: 2px;
    background: var(--gradient-hero);
    border-radius: 2px;
    transition: width 0.3s ease;
}

.nav-links a:hover {
    color: var(--text-primary);
}

.nav-links a:hover::after {
    width: 100%;
}

.nav-workspace-btn {
    padding: 0.5rem 1.25rem;
    background: var(--gradient-hero);
    color: var(--text-on-accent);
    border-radius: 100px;
    font-size: 0.85rem;
    font-weight: 500;
    text-decoration: none;
    transition: var(--transition);
    box-shadow: 0 4px 14px rgba(99, 102, 241, 0.3);
}

.nav-workspace-btn:hover {
    transform: translateY(-2px);
    box-shadow: 0 6px 20px rgba(99, 102, 241, 0.4);
}

/* ---------- Hero 区域 ---------- */
.hero {
    min-height: 100vh;
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    padding: 6rem 2rem 2rem;
    position: relative;
}

.hero-content {
    max-width: 900px;
    width: 100%;
    text-align: center;
}

.hero-greeting {
    padding: 3rem 3rem;
}

.hero-tag {
    font-size: 0.85rem;
    color: var(--accent-primary);
    font-weight: 500;
    letter-spacing: 0.08em;
    text-transform: uppercase;
    margin-bottom: 1.5rem;
}

.hero-title {
    font-size: clamp(2rem, 5vw, 3.5rem);
    font-weight: 700;
    line-height: 1.2;
    letter-spacing: -0.03em;
    color: var(--text-primary);
    margin-bottom: 1.5rem;
    text-shadow: var(--text-shadow);
}

.gradient-text {
    background: var(--gradient-hero);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.hero-subtitle {
    font-size: 1.05rem;
    color: var(--text-secondary);
    line-height: 1.7;
    margin-bottom: 2.5rem;
    font-weight: 300;
    text-shadow: var(--text-shadow);
}

.hero-stats {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 0;
    flex-wrap: wrap;
    padding-top: 2rem;
    border-top: 1px solid rgba(0, 0, 0, 0.06);
}

.stat-item {
    display: flex;
    flex-direction: column;
    align-items: center;
    padding: 0 1.5rem;
}

.stat-num {
    font-size: 2rem;
    font-weight: 700;
    background: var(--gradient-hero);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
    letter-spacing: -0.02em;
}

.stat-label {
    font-size: 0.8rem;
    color: var(--text-tertiary);
    margin-top: 0.25rem;
}

.stat-divider {
    width: 1px;
    height: 36px;
    background: rgba(0, 0, 0, 0.1);
}

.scroll-hint {
    margin-top: 3rem;
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 0.5rem;
    color: var(--text-tertiary);
    font-size: 0.8rem;
    animation: bounce 2s ease-in-out infinite;
}

.scroll-arrow {
    width: 1px;
    height: 30px;
    background: linear-gradient(to bottom, var(--text-tertiary), transparent);
}

@keyframes bounce {
    0%, 100% { transform: translateY(0); }
    50% { transform: translateY(8px); }
}

/* ---------- 通用 Section ---------- */
.section {
    max-width: 1200px;
    margin: 0 auto;
    padding: 6rem 2rem;
}

.section-accent {
    max-width: none;
    margin: 0;
    padding-left: 0;
    padding-right: 0;
}

.section-accent > * {
    max-width: 1200px;
    margin-left: auto;
    margin-right: auto;
    padding-left: 2rem;
    padding-right: 2rem;
}

.section-header {
    text-align: center;
    margin-bottom: 3.5rem;
}

.section-tag {
    display: inline-block;
    font-size: 0.8rem;
    color: var(--accent-primary);
    font-weight: 600;
    letter-spacing: 0.1em;
    margin-bottom: 0.75rem;
}

.section-title {
    font-size: clamp(1.75rem, 4vw, 2.5rem);
    font-weight: 700;
    letter-spacing: -0.02em;
    color: var(--text-primary);
    text-shadow: var(--text-shadow);
}

.section-desc {
    font-size: 1.05rem;
    color: var(--text-secondary);
    max-width: 640px;
    margin: 1rem auto 0;
    line-height: 1.7;
    font-weight: 300;
}

/* ---------- 关于我 ---------- */
.about-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 1.5rem;
    margin-bottom: 1.5rem;
}

.about-info, .about-research {
    padding: 2rem;
}

.about-info h3, .about-research h3, .skills-card h3 {
    font-size: 1.15rem;
    font-weight: 600;
    margin-bottom: 1.25rem;
    color: var(--text-primary);
}

.mt-2 {
    margin-top: 2rem;
}

.info-list {
    display: flex;
    flex-direction: column;
    gap: 0.85rem;
}

.info-row {
    display: flex;
    flex-direction: column;
    gap: 0.2rem;
    padding-bottom: 0.85rem;
    border-bottom: 1px solid rgba(0, 0, 0, 0.05);
}

.info-row:last-child {
    border-bottom: none;
    padding-bottom: 0;
}

.info-label {
    font-size: 0.8rem;
    color: var(--text-tertiary);
    font-weight: 500;
}

.info-value {
    font-size: 0.95rem;
    color: var(--text-primary);
    font-weight: 400;
}

.research-tags {
    display: flex;
    flex-wrap: wrap;
    gap: 0.6rem;
    margin-bottom: 0.5rem;
}

.research-tag {
    padding: 0.4rem 0.9rem;
    background: rgba(99, 102, 241, 0.1);
    color: var(--accent-primary);
    border-radius: 100px;
    font-size: 0.82rem;
    font-weight: 500;
}

.achievement-list {
    list-style: none;
    display: flex;
    flex-direction: column;
    gap: 0.6rem;
}

.achievement-list li {
    font-size: 0.92rem;
    color: var(--text-secondary);
    padding-left: 1.25rem;
    position: relative;
    line-height: 1.6;
}

.achievement-list li::before {
    content: '';
    position: absolute;
    left: 0;
    top: 0.55rem;
    width: 6px;
    height: 6px;
    background: var(--gradient-hero);
    border-radius: 50%;
}

.skills-card {
    padding: 2rem;
}

.skill-cloud {
    display: flex;
    flex-wrap: wrap;
    gap: 0.75rem;
}

.skill-chip {
    padding: 0.6rem 1.2rem;
    background: rgba(255, 255, 255, 0.5);
    border: 1px solid var(--glass-border);
    border-radius: 100px;
    font-size: 0.88rem;
    font-weight: 500;
    color: var(--text-primary);
    transition: var(--transition);
    cursor: default;
}

.skill-chip:hover {
    background: var(--gradient-hero);
    color: var(--text-on-accent);
    border-color: transparent;
    transform: translateY(-2px);
}

/* ---------- 妇女赋能 ---------- */
.timeline-card {
    padding: 2.5rem;
    margin-bottom: 2rem;
}

.timeline-card h3 {
    font-size: 1.2rem;
    font-weight: 600;
    margin-bottom: 2rem;
    color: var(--text-primary);
}

.timeline {
    position: relative;
    padding-left: 2rem;
}

.timeline::before {
    content: '';
    position: absolute;
    left: 8px;
    top: 8px;
    bottom: 8px;
    width: 2px;
    background: linear-gradient(to bottom, var(--accent-primary), var(--accent-secondary), var(--accent-tertiary));
    border-radius: 2px;
}

.timeline-item {
    position: relative;
    margin-bottom: 1.25rem;
}

.timeline-item:last-child {
    margin-bottom: 0;
}

.timeline-dot {
    position: absolute;
    left: -2rem;
    top: 1.5rem;
    width: 18px;
    height: 18px;
    background: var(--bg-base);
    border: 3px solid var(--accent-primary);
    border-radius: 50%;
    z-index: 1;
    transition: var(--transition);
}

.timeline-item:hover .timeline-dot {
    background: var(--accent-primary);
    transform: scale(1.2);
}

.timeline-date {
    font-size: 0.8rem;
    font-weight: 600;
    color: var(--accent-primary);
    letter-spacing: 0.05em;
}

.timeline-content h4 {
    font-size: 1rem;
    font-weight: 600;
    color: var(--text-primary);
    margin: 0.3rem 0 0.35rem;
}

.timeline-content p {
    font-size: 0.88rem;
    color: var(--text-secondary);
    line-height: 1.5;
}

.module-grid {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 1.25rem;
    margin-bottom: 2rem;
}

.module-card {
    padding: 1.75rem 1.5rem;
    text-align: center;
}

.module-icon {
    font-size: 2rem;
    margin-bottom: 1rem;
}

.module-card h4 {
    font-size: 1rem;
    font-weight: 600;
    color: var(--text-primary);
    margin-bottom: 0.6rem;
}

.module-card p {
    font-size: 0.85rem;
    color: var(--text-secondary);
    line-height: 1.55;
}

.benefit-card {
    padding: 2rem;
}

.benefit-card h3 {
    font-size: 1.15rem;
    font-weight: 600;
    margin-bottom: 1.5rem;
    color: var(--text-primary);
}

.benefit-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 1.5rem;
}

.benefit-item {
    display: flex;
    align-items: center;
    gap: 0.75rem;
    padding: 1.25rem;
    background: rgba(255, 255, 255, 0.4);
    border-radius: var(--radius-md);
    transition: var(--transition);
}

.benefit-item:hover {
    background: rgba(255, 255, 255, 0.6);
}

.benefit-emoji {
    font-size: 1.75rem;
}

.benefit-item span:last-child {
    font-size: 0.9rem;
    color: var(--text-primary);
    font-weight: 500;
}

/* ---------- 课程 ---------- */
.course-grid {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 1.5rem;
}

.course-card {
    padding: 2rem;
}

.course-type {
    display: inline-block;
    padding: 0.3rem 0.8rem;
    border-radius: 100px;
    font-size: 0.75rem;
    font-weight: 600;
    margin-bottom: 1rem;
    letter-spacing: 0.03em;
}

.type-empower { background: rgba(236, 72, 153, 0.15); color: #db2777; }
.type-uni { background: rgba(99, 102, 241, 0.15); color: #4f46e5; }
.type-pro { background: rgba(16, 185, 129, 0.15); color: #059669; }
.type-general { background: rgba(245, 158, 11, 0.15); color: #d97706; }

.course-card h4 {
    font-size: 1.15rem;
    font-weight: 600;
    color: var(--text-primary);
    margin-bottom: 0.6rem;
    line-height: 1.4;
}

.course-card p {
    font-size: 0.9rem;
    color: var(--text-secondary);
    line-height: 1.55;
    margin-bottom: 1rem;
}

.course-meta {
    font-size: 0.82rem;
    color: var(--text-tertiary);
    font-weight: 500;
}

/* ---------- 工具 ---------- */
.tool-grid {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 1.25rem;
    margin-bottom: 1.5rem;
}

.tool-card {
    padding: 1.75rem 1.5rem;
    text-decoration: none;
    color: inherit;
    display: flex;
    flex-direction: column;
}

.tool-header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    margin-bottom: 1rem;
}

.tool-badge {
    padding: 0.25rem 0.65rem;
    border-radius: 100px;
    font-size: 0.72rem;
    font-weight: 600;
}

.badge-pro { background: rgba(99, 102, 241, 0.15); color: #4f46e5; }
.badge-all { background: rgba(16, 185, 129, 0.15); color: #059669; }
.badge-template { background: rgba(245, 158, 11, 0.15); color: #d97706; }

.tool-cat {
    font-size: 0.75rem;
    color: var(--text-tertiary);
    font-weight: 500;
}

.tool-card h4 {
    font-size: 1.05rem;
    font-weight: 600;
    color: var(--text-primary);
    margin-bottom: 0.4rem;
}

.tool-card p {
    font-size: 0.85rem;
    color: var(--text-secondary);
    line-height: 1.5;
    margin-bottom: 1rem;
    flex-grow: 1;
}

.tool-link {
    font-size: 0.82rem;
    color: var(--accent-primary);
    font-weight: 500;
}

.tool-link-pending {
    color: var(--text-tertiary);
}

.resource-nav {
    padding: 2rem;
}

.resource-nav h4 {
    font-size: 1.1rem;
    font-weight: 600;
    margin-bottom: 1.25rem;
}

.resource-levels {
    display: flex;
    flex-direction: column;
    gap: 0.85rem;
}

.resource-level {
    display: flex;
    align-items: center;
    gap: 1rem;
    padding: 0.85rem 1.25rem;
    background: rgba(255, 255, 255, 0.4);
    border-radius: var(--radius-sm);
}

.level-label {
    font-size: 0.82rem;
    font-weight: 600;
    color: var(--accent-primary);
    min-width: 60px;
}

.level-content {
    font-size: 0.88rem;
    color: var(--text-secondary);
}

/* ---------- 视频 ---------- */
.video-placeholder-card {
    padding: 4rem 2rem;
    text-align: center;
}

.video-categories {
    display: flex;
    justify-content: center;
    gap: 1rem;
    flex-wrap: wrap;
    margin-bottom: 2.5rem;
}

.video-cat {
    padding: 0.5rem 1.25rem;
    background: rgba(99, 102, 241, 0.1);
    color: var(--accent-primary);
    border-radius: 100px;
    font-size: 0.85rem;
    font-weight: 500;
}

.video-coming-icon {
    font-size: 3rem;
    margin-bottom: 1rem;
    opacity: 0.5;
}

.video-coming p {
    color: var(--text-secondary);
    font-size: 1rem;
}

.video-coming-sub {
    font-size: 0.85rem !important;
    color: var(--text-tertiary) !important;
    margin-top: 0.3rem;
}

/* ---------- 下载专区 ---------- */
.download-grid {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 1.25rem;
    margin-bottom: 1.5rem;
}

.download-card {
    padding: 1.75rem 1.5rem;
    text-align: center;
    display: flex;
    flex-direction: column;
    align-items: center;
}

.download-icon {
    font-size: 2.25rem;
    margin-bottom: 1rem;
}

.download-card h4 {
    font-size: 1rem;
    font-weight: 600;
    color: var(--text-primary);
    margin-bottom: 0.5rem;
    line-height: 1.4;
}

.download-card p {
    font-size: 0.82rem;
    color: var(--text-secondary);
    line-height: 1.5;
    margin-bottom: 1.25rem;
    flex-grow: 1;
}

.download-btn {
    padding: 0.55rem 1.5rem;
    border: none;
    border-radius: 100px;
    font-size: 0.85rem;
    font-weight: 500;
    cursor: pointer;
    transition: var(--transition);
    font-family: inherit;
}

.download-ready {
    background: var(--gradient-hero);
    color: var(--text-on-accent);
}

.download-ready:hover {
    transform: translateY(-2px);
    box-shadow: 0 4px 14px rgba(99, 102, 241, 0.3);
}

.download-pending {
    background: rgba(0, 0, 0, 0.05);
    color: var(--text-tertiary);
    cursor: not-allowed;
}

.ppt-spec-card {
    padding: 2rem;
}

.ppt-spec-card h4 {
    font-size: 1.1rem;
    font-weight: 600;
    margin-bottom: 0.75rem;
}

.ppt-spec-text {
    font-size: 0.9rem;
    color: var(--text-secondary);
    line-height: 1.7;
}

/* ---------- 业界动态 ---------- */
.news-grid {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 1.25rem;
}

.news-card {
    padding: 1.75rem 1.25rem;
    text-align: center;
    text-decoration: none;
    color: inherit;
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 0.75rem;
}

.news-icon {
    font-size: 2rem;
}

.news-title {
    font-size: 0.92rem;
    font-weight: 500;
    color: var(--text-primary);
}

/* ---------- 联系 ---------- */
.section-contact {
    padding-bottom: 4rem;
}

.contact-card {
    padding: 3rem;
    text-align: center;
}

.contact-card .section-tag {
    margin-bottom: 0.5rem;
}

.contact-card .section-title {
    margin-bottom: 2.5rem;
}

.contact-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 1.25rem;
}

.contact-item {
    display: flex;
    align-items: center;
    gap: 1rem;
    padding: 1.25rem;
    background: rgba(255, 255, 255, 0.4);
    border-radius: var(--radius-md);
    text-decoration: none;
    color: inherit;
    transition: var(--transition);
    text-align: left;
}

.contact-item:hover {
    background: rgba(255, 255, 255, 0.6);
    transform: translateY(-3px);
}

.contact-icon {
    font-size: 1.75rem;
}

.contact-label {
    display: block;
    font-size: 0.78rem;
    color: var(--text-tertiary);
    margin-bottom: 0.15rem;
}

.contact-value {
    display: block;
    font-size: 0.9rem;
    color: var(--text-primary);
    font-weight: 500;
}

.contact-pending {
    color: var(--text-tertiary) !important;
    font-weight: 400 !important;
    font-style: italic;
}

/* ---------- 页脚 ---------- */
.footer {
    text-align: center;
    padding: 2.5rem 2rem;
    color: var(--text-tertiary);
    font-size: 0.85rem;
    border-top: 1px solid rgba(0, 0, 0, 0.05);
}

.footer-sub {
    margin-top: 0.3rem;
    font-size: 0.78rem;
    color: var(--text-tertiary);
}

/* ---------- 滚动动画 ---------- */
.fade-in {
    opacity: 0;
    transform: translateY(30px);
    transition: opacity 0.8s ease, transform 0.8s ease;
}

.fade-in.visible {
    opacity: 1;
    transform: translateY(0);
}

/* ---------- 响应式 ---------- */
@media (max-width: 1024px) {
    .module-grid, .tool-grid, .download-grid, .news-grid {
        grid-template-columns: repeat(2, 1fr);
    }

    .about-grid {
        grid-template-columns: 1fr;
    }

    .benefit-grid {
        grid-template-columns: 1fr;
    }
}

@media (max-width: 768px) {
    .nav-links {
        display: none;
    }

    .nav-inner {
        padding: 0.75rem 1.25rem;
    }

    .section {
        padding: 4rem 1.25rem;
    }

    .section-accent > * {
        padding-left: 1.25rem;
        padding-right: 1.25rem;
    }

    .hero {
        padding: 5rem 1.25rem 2rem;
    }

    .hero-greeting {
        padding: 2rem 1.5rem;
    }

    .hero-stats {
        gap: 0.5rem;
    }

    .stat-item {
        padding: 0.5rem 0.75rem;
    }

    .stat-num {
        font-size: 1.5rem;
    }

    .stat-label {
        font-size: 0.7rem;
    }

    .stat-divider {
        height: 24px;
    }

    .course-grid, .contact-grid {
        grid-template-columns: 1fr;
    }

    .module-grid, .tool-grid, .download-grid, .news-grid {
        grid-template-columns: 1fr;
    }

    .contact-card {
        padding: 2rem 1.5rem;
    }

    .timeline {
        padding-left: 1.5rem;
    }
}