/* ============================================
   有道翻译 - 全新视觉设计系统
   ============================================ */

:root {
    /* 主色调 */
    --primary: #4F46E5;
    --primary-light: #818CF8;
    --primary-dark: #3730A3;
    --accent: #E23A3A;
    --accent-light: #F87171;

    /* 背景 */
    --bg-primary: #0B0D1A;
    --bg-secondary: #111527;
    --bg-card: rgba(17, 21, 39, 0.6);
    --bg-glass: rgba(255, 255, 255, 0.03);

    /* 文字 */
    --text-primary: #F1F5F9;
    --text-secondary: #94A3B8;
    --text-muted: #64748B;

    /* 边框 */
    --border-subtle: rgba(148, 163, 184, 0.08);
    --border-card: rgba(148, 163, 184, 0.12);
    --border-active: rgba(79, 70, 229, 0.4);

    /* 阴影 */
    --shadow-sm: 0 1px 2px rgba(0, 0, 0, 0.3);
    --shadow-md: 0 4px 16px rgba(0, 0, 0, 0.4);
    --shadow-lg: 0 8px 32px rgba(0, 0, 0, 0.5);
    --shadow-glow: 0 0 40px rgba(79, 70, 229, 0.15);

    /* 圆角 */
    --radius-sm: 8px;
    --radius-md: 14px;
    --radius-lg: 20px;
    --radius-xl: 28px;
    --radius-full: 9999px;

    /* 过渡 */
    --ease-out: cubic-bezier(0.16, 1, 0.3, 1);
    --ease-spring: cubic-bezier(0.34, 1.56, 0.64, 1);
}

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

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

body {
    font-family: 'Inter', 'PingFang SC', 'Microsoft YaHei', -apple-system, sans-serif;
    min-height: 100vh;
    color: var(--text-primary);
    background: var(--bg-primary);
    overflow-x: hidden;
    line-height: 1.6;
}

/* ============================================
   动态背景
   ============================================ */
.bg-canvas {
    position: fixed;
    top: 0; left: 0;
    width: 100%; height: 100%;
    pointer-events: none;
    z-index: 0;
}

/* 网格背景 */
.grid-pattern {
    position: fixed;
    top: 0; left: 0;
    width: 100%; height: 100%;
    background-image:
        linear-gradient(rgba(148, 163, 184, 0.03) 1px, transparent 1px),
        linear-gradient(90deg, rgba(148, 163, 184, 0.03) 1px, transparent 1px);
    background-size: 60px 60px;
    pointer-events: none;
    z-index: 0;
    mask-image: radial-gradient(ellipse 80% 80% at 50% 0%, black 40%, transparent 80%);
    -webkit-mask-image: radial-gradient(ellipse 80% 80% at 50% 0%, black 40%, transparent 80%);
}

/* 光晕效果 */
.aurora {
    position: fixed;
    border-radius: 50%;
    filter: blur(120px);
    pointer-events: none;
    z-index: 0;
    opacity: 0.4;
}

.aurora-1 {
    width: 700px; height: 700px;
    background: var(--primary);
    top: -300px; right: -200px;
    animation: auroraFloat 15s ease-in-out infinite;
}

.aurora-2 {
    width: 500px; height: 500px;
    background: #7C3AED;
    bottom: -200px; left: -150px;
    animation: auroraFloat 18s ease-in-out infinite reverse;
    opacity: 0.3;
}

.aurora-3 {
    width: 400px; height: 400px;
    background: var(--accent);
    top: 50%; left: 50%;
    transform: translate(-50%, -50%);
    animation: auroraFloat 20s ease-in-out infinite;
    opacity: 0.15;
}

@keyframes auroraFloat {
    0%, 100% { transform: translate(0, 0) scale(1); }
    25% { transform: translate(80px, -40px) scale(1.1); }
    50% { transform: translate(-30px, 60px) scale(0.95); }
    75% { transform: translate(-60px, -30px) scale(1.05); }
}

/* 浮动粒子 */
.particles {
    position: fixed;
    top: 0; left: 0;
    width: 100%; height: 100%;
    pointer-events: none;
    z-index: 0;
}

.particle {
    position: absolute;
    width: 2px;
    height: 2px;
    background: var(--primary-light);
    border-radius: 50%;
    animation: particleRise linear infinite;
}

@keyframes particleRise {
    0% {
        transform: translateY(100vh) scale(0);
        opacity: 0;
    }
    10% { opacity: 1; }
    90% { opacity: 1; }
    100% {
        transform: translateY(-10vh) scale(1);
        opacity: 0;
    }
}

/* ============================================
   导航栏
   ============================================ */
.nav {
    position: fixed;
    top: 0; left: 0;
    width: 100%;
    z-index: 100;
    padding: 0 24px;
    transition: all 0.3s var(--ease-out);
}

.nav.scrolled {
    background: rgba(11, 13, 26, 0.85);
    backdrop-filter: blur(20px);
    -webkit-backdrop-filter: blur(20px);
    border-bottom: 1px solid var(--border-subtle);
}

.nav-inner {
    max-width: 1200px;
    margin: 0 auto;
    display: flex;
    align-items: center;
    justify-content: space-between;
    height: 72px;
}

/* Logo */
.nav-brand {
    display: flex;
    align-items: center;
    gap: 10px;
    text-decoration: none;
    font-weight: 700;
    font-size: 18px;
    color: var(--text-primary);
    transition: opacity 0.2s;
}

.nav-brand:hover { opacity: 0.85; }

.nav-brand-icon {
    width: 36px;
    height: 36px;
    background: linear-gradient(135deg, var(--primary), var(--primary-dark));
    border-radius: var(--radius-sm);
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 18px;
    color: white;
}

/* 导航链接 */
.nav-links {
    display: flex;
    align-items: center;
    gap: 4px;
    background: var(--bg-glass);
    border: 1px solid var(--border-subtle);
    border-radius: var(--radius-full);
    padding: 4px;
}

.nav-links a {
    padding: 8px 20px;
    border-radius: var(--radius-full);
    text-decoration: none;
    font-size: 14px;
    font-weight: 500;
    color: var(--text-secondary);
    transition: all 0.25s var(--ease-out);
}

.nav-links a:hover {
    color: var(--text-primary);
    background: rgba(255, 255, 255, 0.05);
}

.nav-links a.active {
    color: white;
    background: var(--primary);
}

/* ============================================
   主页容器
   ============================================ */
.page {
    position: relative;
    z-index: 1;
    min-height: 100vh;
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 24px;
}

/* ============================================
   英雄区
   ============================================ */
.hero {
    text-align: center;
    padding: 160px 24px 100px;
    position: relative;
}

/* Badge */
.hero-badge {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    padding: 6px 16px 6px 6px;
    background: rgba(79, 70, 229, 0.1);
    border: 1px solid rgba(79, 70, 229, 0.2);
    border-radius: var(--radius-full);
    font-size: 13px;
    color: var(--primary-light);
    margin-bottom: 32px;
    animation: fadeInUp 0.6s var(--ease-out);
}

.hero-badge-dot {
    width: 8px;
    height: 8px;
    border-radius: 50%;
    background: var(--primary-light);
    animation: pulse-dot 2s ease-in-out infinite;
}

@keyframes pulse-dot {
    0%, 100% { opacity: 1; }
    50% { opacity: 0.4; }
}

/* 标题 */
.hero-title {
    font-size: clamp(40px, 6vw, 72px);
    font-weight: 800;
    letter-spacing: -0.03em;
    line-height: 1.1;
    margin-bottom: 24px;
    animation: fadeInUp 0.6s var(--ease-out) 0.1s both;
}

.hero-title .gradient-text {
    background: linear-gradient(135deg, var(--primary-light) 0%, #C084FC 50%, var(--accent-light) 100%);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
    background-size: 200% 200%;
    animation: gradientShift 4s ease-in-out infinite;
}

@keyframes gradientShift {
    0%, 100% { background-position: 0% 50%; }
    50% { background-position: 100% 50%; }
}

.hero-desc {
    font-size: 18px;
    color: var(--text-secondary);
    max-width: 580px;
    margin: 0 auto 48px;
    line-height: 1.8;
    animation: fadeInUp 0.6s var(--ease-out) 0.2s both;
}

/* CTA按钮组 */
.hero-actions {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 16px;
    flex-wrap: wrap;
    animation: fadeInUp 0.6s var(--ease-out) 0.3s both;
}

/* ============================================
   按钮系统
   ============================================ */
.btn {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    padding: 14px 32px;
    border-radius: var(--radius-full);
    font-size: 15px;
    font-weight: 600;
    font-family: inherit;
    text-decoration: none;
    cursor: pointer;
    border: none;
    transition: all 0.3s var(--ease-out);
    position: relative;
    overflow: hidden;
}

.btn-primary {
    background: linear-gradient(135deg, var(--primary), #6366F1);
    color: white;
    box-shadow: 0 4px 20px rgba(79, 70, 229, 0.3);
}

.btn-primary:hover {
    transform: translateY(-2px);
    box-shadow: 0 8px 30px rgba(79, 70, 229, 0.45);
}

.btn-primary:active {
    transform: translateY(0);
}

.btn-primary .btn-icon {
    width: 18px; height: 18px;
    transition: transform 0.3s var(--ease-out);
}

.btn-primary:hover .btn-icon {
    transform: translateY(2px);
}

.btn-secondary {
    background: var(--bg-glass);
    color: var(--text-primary);
    border: 1px solid var(--border-card);
}

.btn-secondary:hover {
    background: rgba(255, 255, 255, 0.06);
    border-color: rgba(255, 255, 255, 0.15);
}

/* ============================================
   翻译演示卡片
   ============================================ */
.translate-demo {
    max-width: 640px;
    margin: 0 auto 80px;
    background: var(--bg-card);
    border: 1px solid var(--border-card);
    border-radius: var(--radius-xl);
    padding: 6px;
    backdrop-filter: blur(20px);
    animation: fadeInUp 0.6s var(--ease-out) 0.4s both;
}

.translate-demo-inner {
    background: rgba(255, 255, 255, 0.02);
    border-radius: calc(var(--radius-xl) - 6px);
    padding: 24px;
}

.translate-input-row {
    display: flex;
    gap: 12px;
}

.translate-input {
    flex: 1;
    background: transparent;
    border: none;
    outline: none;
    color: var(--text-primary);
    font-size: 16px;
    font-family: inherit;
    padding: 12px 16px;
    resize: none;
    min-height: 60px;
}

.translate-input::placeholder {
    color: var(--text-muted);
}

.translate-swap-btn {
    width: 40px; height: 40px;
    background: rgba(79, 70, 229, 0.15);
    border: 1px solid rgba(79, 70, 229, 0.2);
    border-radius: var(--radius-sm);
    display: flex;
    align-items: center;
    justify-content: center;
    cursor: pointer;
    color: var(--primary-light);
    transition: all 0.2s;
    flex-shrink: 0;
    align-self: center;
}

.translate-swap-btn:hover {
    background: rgba(79, 70, 229, 0.25);
}

.translate-divider {
    height: 1px;
    background: var(--border-card);
    margin: 16px 0;
}

.translate-lang-bar {
    display: flex;
    align-items: center;
    justify-content: space-between;
    margin-bottom: 16px;
}

.lang-tag {
    font-size: 12px;
    color: var(--text-muted);
    background: rgba(255, 255, 255, 0.03);
    padding: 4px 10px;
    border-radius: var(--radius-full);
    border: 1px solid var(--border-subtle);
}

.translate-output {
    min-height: 60px;
    padding: 12px 16px;
    color: var(--text-secondary);
    font-size: 16px;
}

.translate-actions {
    display: flex;
    gap: 8px;
    justify-content: flex-end;
    margin-top: 12px;
}

.translate-actions .btn-icon-only {
    width: 36px; height: 36px;
    display: flex;
    align-items: center;
    justify-content: center;
    background: transparent;
    border: 1px solid var(--border-subtle);
    border-radius: var(--radius-sm);
    color: var(--text-muted);
    cursor: pointer;
    transition: all 0.2s;
}

.translate-actions .btn-icon-only:hover {
    color: var(--text-primary);
    background: rgba(255, 255, 255, 0.05);
    border-color: var(--border-card);
}

/* ============================================
   语言选择器按钮组
   ============================================ */
.lang-selector {
    display: flex;
    justify-content: center;
    gap: 6px;
    margin-bottom: 72px;
    flex-wrap: wrap;
    animation: fadeInUp 0.6s var(--ease-out) 0.5s both;
}

.lang-chip {
    padding: 8px 16px;
    background: var(--bg-glass);
    border: 1px solid var(--border-subtle);
    border-radius: var(--radius-full);
    color: var(--text-secondary);
    font-size: 13px;
    cursor: pointer;
    transition: all 0.25s var(--ease-out);
}

.lang-chip:hover {
    color: var(--text-primary);
    border-color: var(--border-card);
    background: rgba(255, 255, 255, 0.04);
}

.lang-chip.active {
    color: white;
    background: rgba(79, 70, 229, 0.2);
    border-color: rgba(79, 70, 229, 0.35);
}

/* ============================================
   数据统计区
   ============================================ */
.stats {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 1px;
    background: var(--border-subtle);
    border-radius: var(--radius-xl);
    overflow: hidden;
    max-width: 900px;
    margin: 0 auto 100px;
    border: 1px solid var(--border-subtle);
}

.stat-item {
    background: var(--bg-card);
    padding: 36px 24px;
    text-align: center;
    transition: background 0.3s;
}

.stat-item:hover {
    background: rgba(17, 21, 39, 0.8);
}

.stat-number {
    font-size: 48px;
    font-weight: 800;
    letter-spacing: -0.02em;
    background: linear-gradient(135deg, var(--primary-light), var(--primary));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
    line-height: 1;
    margin-bottom: 8px;
}

.stat-label {
    font-size: 14px;
    color: var(--text-secondary);
}

.stat-suffix {
    font-size: 20px;
    font-weight: 700;
    -webkit-text-fill-color: transparent;
    background: linear-gradient(135deg, var(--primary-light), var(--primary));
    -webkit-background-clip: text;
    background-clip: text;
}

/* ============================================
   功能区标题
   ============================================ */
.section-header {
    text-align: center;
    margin-bottom: 56px;
}

.section-label {
    display: inline-block;
    font-size: 12px;
    font-weight: 600;
    letter-spacing: 0.08em;
    text-transform: uppercase;
    color: var(--primary-light);
    margin-bottom: 16px;
}

.section-title {
    font-size: clamp(28px, 4vw, 40px);
    font-weight: 800;
    letter-spacing: -0.02em;
    margin-bottom: 16px;
}

.section-desc {
    font-size: 16px;
    color: var(--text-secondary);
    max-width: 480px;
    margin: 0 auto;
}

/* ============================================
   功能卡片网格
   ============================================ */
.features {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 20px;
    margin-bottom: 120px;
}

.feature-card {
    background: var(--bg-card);
    border: 1px solid var(--border-card);
    border-radius: var(--radius-lg);
    padding: 36px;
    position: relative;
    overflow: hidden;
    transition: all 0.4s var(--ease-out);
    cursor: default;
}

.feature-card::before {
    content: '';
    position: absolute;
    top: 0; left: 0;
    width: 100%; height: 100%;
    background: radial-gradient(600px circle at var(--mouse-x, 50%) var(--mouse-y, 50%),
        rgba(79, 70, 229, 0.08), transparent 50%);
    opacity: 0;
    transition: opacity 0.4s;
}

.feature-card:hover::before {
    opacity: 1;
}

.feature-card:hover {
    border-color: var(--border-active);
    transform: translateY(-4px);
    box-shadow: var(--shadow-glow);
}

.feature-icon-wrap {
    width: 48px;
    height: 48px;
    background: rgba(79, 70, 229, 0.1);
    border-radius: var(--radius-md);
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 22px;
    margin-bottom: 20px;
    position: relative;
    z-index: 1;
}

.feature-card h3 {
    font-size: 19px;
    font-weight: 700;
    margin-bottom: 10px;
    position: relative;
    z-index: 1;
}

.feature-card p {
    font-size: 14px;
    color: var(--text-secondary);
    line-height: 1.7;
    position: relative;
    z-index: 1;
}

/* ============================================
   CTA区块
   ============================================ */
.cta-section {
    text-align: center;
    padding: 80px 24px 120px;
    position: relative;
}

.cta-card {
    max-width: 700px;
    margin: 0 auto;
    padding: 64px 48px;
    background: var(--bg-card);
    border: 1px solid var(--border-card);
    border-radius: var(--radius-xl);
    position: relative;
    overflow: hidden;
}

.cta-card::before {
    content: '';
    position: absolute;
    top: -50%;
    left: -50%;
    width: 200%;
    height: 200%;
    background: radial-gradient(circle at 30% 50%, rgba(79, 70, 229, 0.08) 0%, transparent 50%);
}

.cta-card h2 {
    font-size: 32px;
    font-weight: 800;
    margin-bottom: 16px;
    position: relative;
}

.cta-card p {
    color: var(--text-secondary);
    margin-bottom: 32px;
    position: relative;
    font-size: 16px;
}

/* ============================================
   页脚
   ============================================ */
.footer {
    border-top: 1px solid var(--border-subtle);
    padding: 32px 24px;
    text-align: center;
    position: relative;
    z-index: 1;
}

.footer-text {
    font-size: 13px;
    color: var(--text-muted);
}

/* ============================================
   下载页面
   ============================================ */
.download-page-wrap {
    display: flex;
    align-items: center;
    justify-content: center;
    min-height: 100vh;
    padding: 120px 24px 80px;
}

.download-layout {
    display: flex;
    align-items: center;
    gap: 100px;
    max-width: 1000px;
    width: 100%;
    animation: fadeInUp 0.6s var(--ease-out);
}

/* 下载页视觉区 */
.download-visual-wrap {
    flex-shrink: 0;
    width: 320px;
    height: 380px;
    position: relative;
    display: flex;
    align-items: center;
    justify-content: center;
}

.download-app-icon {
    width: 140px;
    height: 140px;
    background: linear-gradient(135deg, var(--primary), #6366F1);
    border-radius: 32px;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 48px;
    font-weight: 800;
    color: white;
    box-shadow: 0 20px 60px rgba(79, 70, 229, 0.4);
    animation: floatApp 4s ease-in-out infinite;
    position: relative;
}

.download-app-icon::after {
    content: '';
    position: absolute;
    inset: -4px;
    border-radius: 36px;
    border: 2px solid rgba(79, 70, 229, 0.3);
    animation: pulseRing 2s ease-in-out infinite;
}

@keyframes floatApp {
    0%, 100% { transform: translateY(0); }
    50% { transform: translateY(-12px); }
}

@keyframes pulseRing {
    0%, 100% { opacity: 0.5; transform: scale(1); }
    50% { opacity: 0; transform: scale(1.1); }
}

/* 下载信息区 */
.download-info-wrap {
    flex: 1;
}

.download-info-badge {
    display: inline-block;
    padding: 6px 14px;
    background: rgba(79, 70, 229, 0.1);
    border: 1px solid rgba(79, 70, 229, 0.2);
    border-radius: var(--radius-full);
    font-size: 12px;
    font-weight: 600;
    color: var(--primary-light);
    margin-bottom: 20px;
}

.download-title {
    font-size: 48px;
    font-weight: 800;
    letter-spacing: -0.02em;
    margin-bottom: 8px;
}

.download-version {
    font-size: 18px;
    color: var(--primary-light);
    font-weight: 600;
    margin-bottom: 28px;
}

.download-meta-list {
    display: flex;
    flex-wrap: wrap;
    gap: 20px;
    margin-bottom: 24px;
}

.download-meta-item {
    font-size: 14px;
    color: var(--text-secondary);
    display: flex;
    align-items: center;
    gap: 6px;
}

.download-meta-item .meta-icon {
    font-size: 16px;
}

.download-feature-list {
    margin-bottom: 32px;
}

.download-feature-item {
    display: flex;
    align-items: center;
    gap: 10px;
    padding: 8px 0;
    font-size: 15px;
    color: var(--text-secondary);
}

.download-feature-item .check-icon {
    width: 20px; height: 20px;
    background: rgba(34, 197, 94, 0.15);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    color: #22C55E;
    font-size: 11px;
    flex-shrink: 0;
}

.download-btn-group {
    display: flex;
    gap: 14px;
    flex-wrap: wrap;
    margin-bottom: 24px;
}

.download-btn-group .btn-outline {
    background: transparent;
    border: 1px solid var(--border-card);
    color: var(--text-secondary);
    padding: 14px 28px;
    border-radius: var(--radius-full);
    font-size: 15px;
    font-weight: 600;
    font-family: inherit;
    cursor: pointer;
    text-decoration: none;
    transition: all 0.25s;
    display: inline-flex;
    align-items: center;
    gap: 8px;
}

.download-btn-group .btn-outline:hover {
    background: var(--bg-glass);
    border-color: rgba(255, 255, 255, 0.2);
    color: var(--text-primary);
}

.download-update {
    font-size: 13px;
    color: var(--text-muted);
}

/* ============================================
   404 页面
   ============================================ */
.error-page-wrap {
    display: flex;
    align-items: center;
    justify-content: center;
    min-height: 100vh;
    padding: 120px 24px 80px;
    text-align: center;
}

.error-content {
    animation: fadeInUp 0.6s var(--ease-out);
}

.error-visual-area {
    margin-bottom: 32px;
    position: relative;
    display: inline-block;
}

.error-icon-circle {
    width: 120px;
    height: 120px;
    border-radius: 50%;
    background: rgba(79, 70, 229, 0.08);
    border: 2px solid rgba(79, 70, 229, 0.15);
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 52px;
    margin: 0 auto;
    animation: errorFloat 3s ease-in-out infinite;
}

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

.error-code-num {
    font-size: 140px;
    font-weight: 900;
    letter-spacing: -0.04em;
    line-height: 1;
    background: linear-gradient(135deg, var(--primary-light) 0%, #C084FC 50%, var(--accent-light) 100%);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
    background-size: 200% 200%;
    animation: gradientShift 3s ease-in-out infinite;
    margin-bottom: 8px;
}

.error-title {
    font-size: 28px;
    font-weight: 700;
    margin-bottom: 12px;
}

.error-desc {
    font-size: 16px;
    color: var(--text-secondary);
    margin-bottom: 40px;
}

.error-btn-group {
    display: flex;
    gap: 14px;
    justify-content: center;
    flex-wrap: wrap;
}

/* ============================================
   动画
   ============================================ */
@keyframes fadeInUp {
    from {
        opacity: 0;
        transform: translateY(24px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

@keyframes fadeIn {
    from { opacity: 0; }
    to { opacity: 1; }
}

/* 滚动入场动画 */
.animate-on-scroll {
    opacity: 0;
    transform: translateY(30px);
    transition: opacity 0.6s var(--ease-out), transform 0.6s var(--ease-out);
}

.animate-on-scroll.visible {
    opacity: 1;
    transform: translateY(0);
}

/* ============================================
   响应式
   ============================================ */
@media (max-width: 768px) {
    .hero {
        padding: 120px 20px 60px;
    }

    .hero-title {
        font-size: 36px;
    }

    .hero-desc {
        font-size: 15px;
    }

    .translate-demo {
        margin-bottom: 48px;
    }

    .stats {
        grid-template-columns: 1fr;
        max-width: 400px;
        margin: 0 auto 80px;
    }

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

    .feature-card {
        padding: 28px 24px;
    }

    .cta-card {
        padding: 40px 24px;
    }

    .cta-card h2 { font-size: 24px; }

    .lang-selector { gap: 4px; }

    .lang-chip {
        font-size: 12px;
        padding: 6px 12px;
    }

    .section-title { font-size: 28px; }

    .nav-links a { padding: 6px 14px; font-size: 13px; }

    /* 下载页 */
    .download-layout {
        flex-direction: column;
        gap: 48px;
        text-align: center;
    }

    .download-visual-wrap {
        width: 200px;
        height: 240px;
    }

    .download-app-icon {
        width: 100px;
        height: 100px;
        border-radius: 24px;
        font-size: 32px;
    }

    .download-app-icon::after {
        border-radius: 28px;
    }

    .download-title { font-size: 36px; }

    .download-btn-group {
        justify-content: center;
    }

    .download-meta-list {
        justify-content: center;
    }

    .download-feature-list {
        display: inline-block;
        text-align: left;
    }

    /* 404 */
    .error-code-num { font-size: 100px; }
}

@media (max-width: 480px) {
    .hero-title { font-size: 32px; }
    .nav-inner { height: 60px; }
    .nav-brand { font-size: 15px; }
    .nav-brand-icon { width: 30px; height: 30px; font-size: 15px; }
    .stat-number { font-size: 36px; }
    .btn { padding: 12px 24px; font-size: 14px; }
}