/* 全国流量卡办理平台 - 高级现代设计系统 */
:root {
    /* 主色调系统 - 深色主题 */
    --bg-primary: #0f0f23;
    --bg-secondary: #1a1a2e;
    --bg-tertiary: #16213e;
    --bg-card: rgba(255, 255, 255, 0.04);
    --bg-card-hover: rgba(255, 255, 255, 0.08);
    --bg-glass: rgba(255, 255, 255, 0.06);
    
    /* 品牌色彩 - 现代渐变 */
    --brand-primary: #6366f1;
    --brand-secondary: #8b5cf6;
    --brand-accent: #06b6d4;
    --brand-success: #10b981;
    --brand-warning: #f59e0b;
    --brand-danger: #ef4444;
    
    /* 品牌渐变 */
    --gradient-primary: linear-gradient(135deg, #6366f1 0%, #8b5cf6 50%, #06b6d4 100%);
    --gradient-secondary: linear-gradient(135deg, #10b981 0%, #06b6d4 100%);
    --gradient-accent: linear-gradient(135deg, #f59e0b 0%, #ef4444 100%);
    --gradient-dark: linear-gradient(135deg, #1a1a2e 0%, #0f0f23 100%);
    --gradient-card: linear-gradient(145deg, rgba(255,255,255,0.06) 0%, rgba(255,255,255,0.02) 100%);
    
    /* 文字颜色 */
    --text-primary: #f8fafc;
    --text-secondary: #cbd5e1;
    --text-muted: #94a3b8;
    --text-dim: #64748b;
    
    /* 边框和分割线 */
    --border-subtle: rgba(255, 255, 255, 0.08);
    --border-medium: rgba(255, 255, 255, 0.12);
    --border-strong: rgba(255, 255, 255, 0.16);
    
    /* 阴影系统 - 现代风格 */
    --shadow-sm: 0 2px 8px rgba(0, 0, 0, 0.3);
    --shadow: 0 4px 20px rgba(0, 0, 0, 0.4);
    --shadow-md: 0 8px 30px rgba(0, 0, 0, 0.5);
    --shadow-lg: 0 12px 48px rgba(0, 0, 0, 0.6);
    --shadow-xl: 0 20px 80px rgba(0, 0, 0, 0.7);
    --shadow-glow: 0 0 40px rgba(99, 102, 241, 0.3);
    --shadow-card: 0 1px 10px rgba(0, 0, 0, 0.2), inset 0 1px 0 rgba(255, 255, 255, 0.05);
    
    /* 圆角系统 */
    --radius: 6px;
    --radius-md: 10px;
    --radius-lg: 14px;
    --radius-xl: 20px;
    --radius-2xl: 28px;
    --radius-full: 9999px;
    
    /* 间距系统 */
    --spacing-xs: 6px;
    --spacing-sm: 10px;
    --spacing-md: 18px;
    --spacing-lg: 28px;
    --spacing-xl: 40px;
    --spacing-2xl: 56px;
    --spacing-3xl: 72px;
    
    /* 字体系统 */
    --font-size-xs: 0.78rem;
    --font-size-sm: 0.88rem;
    --font-size-base: 1rem;
    --font-size-lg: 1.12rem;
    --font-size-xl: 1.28rem;
    --font-size-2xl: 1.6rem;
    --font-size-3xl: 2rem;
    --font-size-4xl: 2.6rem;
    --font-size-5xl: 3.4rem;
    
    /* 过渡动画 */
    --transition-fast: 180ms cubic-bezier(0.4, 0, 0.2, 1);
    --transition-base: 280ms cubic-bezier(0.4, 0, 0.2, 1);
    --transition-slow: 380ms cubic-bezier(0.4, 0, 0.2, 1);
}

* { margin: 0; padding: 0; box-sizing: border-box; }
html { font-size: 16px; scroll-behavior: smooth; }
body { 
    font-family: -apple-system, BlinkMacSystemFont, "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", "Helvetica Neue", Helvetica, Arial, sans-serif; 
    line-height: 1.7; 
    color: var(--text-secondary); 
    background: linear-gradient(180deg, #0f0f23 0%, #16213e 50%, #0f0f23 100%); 
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
    min-height: 100vh;
}

.container { 
    max-width: 1280px; 
    margin: 0 auto; 
    padding: 0 var(--spacing-lg); 
}

/* ==================== 顶部标识栏 ==================== */
.top-bar {
    background: linear-gradient(135deg, rgba(99, 102, 241, 0.15) 0%, rgba(6, 182, 212, 0.15) 100%);
    color: var(--text-primary);
    padding: 10px 0;
    text-align: center;
    font-size: var(--font-size-sm);
    font-weight: 500;
    position: relative;
    overflow: hidden;
    border-bottom: 1px solid var(--border-subtle);
    backdrop-filter: blur(10px);
}

.top-bar::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: linear-gradient(90deg, transparent, rgba(255,255,255,0.1), transparent);
    animation: shimmer 3s infinite;
}

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

.top-bar span { 
    margin: 0 28px; 
    display: inline-flex;
    align-items: center;
    gap: 8px;
    position: relative;
    z-index: 1;
}

/* ==================== 头部导航 ==================== */
.header {
    background: rgba(15, 15, 35, 0.8);
    backdrop-filter: blur(20px);
    -webkit-backdrop-filter: blur(20px);
    position: sticky;
    top: 0;
    z-index: 1000;
    border-bottom: 1px solid var(--border-subtle);
    transition: all var(--transition-base);
}

.header.scrolled {
    background: rgba(15, 15, 35, 0.95);
    box-shadow: var(--shadow-md);
}

.header-inner {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: var(--spacing-md) 0;
    gap: var(--spacing-xl);
}

.logo {
    display: flex;
    align-items: center;
    gap: 14px;
    text-decoration: none;
}

.logo-icon {
    width: 48px;
    height: 48px;
    background: var(--gradient-primary);
    border-radius: var(--radius-lg);
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.5rem;
    font-weight: 800;
    color: var(--text-primary);
    box-shadow: var(--shadow-glow);
    transition: all var(--transition-base);
}

.logo:hover .logo-icon {
    transform: scale(1.05) rotate(2deg);
    box-shadow: 0 0 50px rgba(99, 102, 241, 0.4);
}

.logo-text {
    font-size: 1.4rem;
    font-weight: 700;
    color: var(--text-primary);
    letter-spacing: -0.3px;
}

.logo-text small {
    display: block;
    font-size: 0.72rem;
    color: var(--text-muted);
    font-weight: 500;
    letter-spacing: 0;
    margin-top: 2px;
}

.nav {
    display: flex;
    align-items: center;
    gap: 10px;
}

.nav a {
    color: var(--text-secondary);
    text-decoration: none;
    padding: 12px 18px;
    border-radius: var(--radius-md);
    font-weight: 500;
    font-size: var(--font-size-sm);
    transition: all var(--transition-base);
    position: relative;
}

.nav a:hover {
    color: var(--text-primary);
    background: rgba(255, 255, 255, 0.06);
}

.nav a.active {
    color: var(--text-primary);
    background: var(--gradient-primary);
    box-shadow: var(--shadow-sm);
}

.nav-btn {
    background: var(--gradient-primary);
    color: var(--text-primary);
    padding: 12px 24px;
    border-radius: var(--radius-md);
    font-weight: 600;
    border: none;
    cursor: pointer;
    transition: all var(--transition-base);
    box-shadow: var(--shadow-sm);
}

.nav-btn:hover {
    transform: translateY(-2px);
    box-shadow: var(--shadow-glow);
}

.mobile-menu-btn {
    display: none;
    background: none;
    border: none;
    color: var(--text-primary);
    font-size: 1.6rem;
    cursor: pointer;
    padding: 8px;
}

/* ==================== 英雄区域 ==================== */
.hero {
    padding: var(--spacing-3xl) 0;
    position: relative;
    overflow: hidden;
    background: linear-gradient(135deg, rgba(99, 102, 241, 0.08) 0%, rgba(6, 182, 212, 0.08) 100%);
}

.hero::before {
    content: '';
    position: absolute;
    top: -50%;
    left: -50%;
    width: 200%;
    height: 200%;
    background: radial-gradient(circle, rgba(99, 102, 241, 0.1) 0%, transparent 50%);
    animation: float 20s ease-in-out infinite;
}

@keyframes float {
    0%, 100% { transform: translate(0, 0) rotate(0deg); }
    50% { transform: translate(5%, 5%) rotate(5deg); }
}

.hero-content {
    text-align: center;
    position: relative;
    z-index: 1;
}

.hero-badge {
    display: inline-flex;
    align-items: center;
    gap: 10px;
    padding: 10px 20px;
    background: var(--bg-card);
    border: 1px solid var(--border-medium);
    border-radius: var(--radius-full);
    font-size: var(--font-size-sm);
    color: var(--text-secondary);
    margin-bottom: var(--spacing-xl);
    backdrop-filter: blur(10px);
    box-shadow: var(--shadow-sm);
}

.hero h1 {
    font-size: clamp(2.4rem, 5vw, 3.8rem);
    font-weight: 800;
    color: var(--text-primary);
    margin-bottom: var(--spacing-md);
    line-height: 1.15;
    letter-spacing: -0.03em;
}

.hero-subtitle {
    font-size: var(--font-size-lg);
    color: var(--text-muted);
    max-width: 720px;
    margin: 0 auto var(--spacing-2xl);
    line-height: 1.8;
}

.btn-group {
    display: flex;
    gap: var(--spacing-md);
    justify-content: center;
    flex-wrap: wrap;
}

.btn {
    display: inline-flex;
    align-items: center;
    gap: 10px;
    padding: 16px 32px;
    border-radius: var(--radius-xl);
    font-size: var(--font-size-base);
    font-weight: 600;
    text-decoration: none;
    border: none;
    cursor: pointer;
    transition: all var(--transition-base);
}

.btn-primary {
    background: var(--gradient-primary);
    color: var(--text-primary);
    box-shadow: var(--shadow-glow);
}

.btn-primary:hover {
    transform: translateY(-3px);
    box-shadow: 0 0 60px rgba(99, 102, 241, 0.5);
}

.btn-outline {
    background: transparent;
    color: var(--text-primary);
    border: 2px solid var(--border-medium);
}

.btn-outline:hover {
    background: rgba(255, 255, 255, 0.06);
    border-color: var(--brand-primary);
    transform: translateY(-2px);
}

.btn-lg {
    padding: 18px 40px;
    font-size: var(--font-size-lg);
}

.hero-stats {
    display: flex;
    justify-content: center;
    gap: var(--spacing-2xl);
    margin-top: var(--spacing-3xl);
    flex-wrap: wrap;
}

.hero-stat {
    text-align: center;
    padding: var(--spacing-md) var(--spacing-lg);
    background: var(--bg-card);
    border: 1px solid var(--border-subtle);
    border-radius: var(--radius-xl);
    backdrop-filter: blur(10px);
    box-shadow: var(--shadow-sm);
    min-width: 140px;
}

.hero-stat-value {
    font-size: var(--font-size-3xl);
    font-weight: 800;
    background: var(--gradient-primary);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
    margin-bottom: 6px;
}

.hero-stat-label {
    font-size: var(--font-size-sm);
    color: var(--text-muted);
    font-weight: 500;
}

/* ==================== 章节通用样式 ==================== */
section {
    padding: var(--spacing-3xl) 0;
}

.section-header {
    text-align: center;
    margin-bottom: var(--spacing-2xl);
}

.section-badge {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    padding: 8px 18px;
    background: var(--bg-card);
    border: 1px solid var(--border-subtle);
    border-radius: var(--radius-full);
    font-size: var(--font-size-sm);
    color: var(--text-muted);
    margin-bottom: var(--spacing-md);
    backdrop-filter: blur(10px);
}

.section-title {
    font-size: var(--font-size-3xl);
    font-weight: 700;
    color: var(--text-primary);
    margin-bottom: var(--spacing-sm);
    letter-spacing: -0.02em;
}

.section-subtitle {
    font-size: var(--font-size-lg);
    color: var(--text-muted);
    max-width: 600px;
    margin: 0 auto;
}

/* ==================== 特色功能 ==================== */
.features {
    background: var(--bg-secondary);
    position: relative;
}

.features::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: radial-gradient(ellipse at 20% 80%, rgba(99, 102, 241, 0.05) 0%, transparent 50%),
                radial-gradient(ellipse at 80% 20%, rgba(6, 182, 212, 0.05) 0%, transparent 50%);
    pointer-events: none;
}

.features-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: var(--spacing-lg);
    position: relative;
    z-index: 1;
}

.feature-card {
    padding: var(--spacing-xl);
    background: var(--gradient-card);
    border: 1px solid var(--border-subtle);
    border-radius: var(--radius-2xl);
    transition: all var(--transition-base);
    box-shadow: var(--shadow-card);
}

.feature-card:hover {
    transform: translateY(-6px);
    background: rgba(255, 255, 255, 0.08);
    border-color: var(--border-medium);
    box-shadow: var(--shadow-lg);
}

.feature-icon {
    width: 64px;
    height: 64px;
    background: var(--gradient-primary);
    border-radius: var(--radius-xl);
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.8rem;
    margin-bottom: var(--spacing-md);
    box-shadow: var(--shadow-sm);
}

.feature-title {
    font-size: var(--font-size-xl);
    font-weight: 700;
    color: var(--text-primary);
    margin-bottom: var(--spacing-sm);
}

.feature-text {
    color: var(--text-muted);
    line-height: 1.7;
    font-size: var(--font-size-base);
}

/* ==================== 运营商套餐 ==================== */
.operators {
    background: var(--bg-primary);
    position: relative;
}

.plans-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: var(--spacing-lg);
}

.plan-card {
    background: var(--gradient-card);
    border: 1px solid var(--border-subtle);
    border-radius: var(--radius-2xl);
    padding: var(--spacing-xl);
    text-align: center;
    position: relative;
    transition: all var(--transition-base);
    box-shadow: var(--shadow-card);
    overflow: hidden;
}

.plan-card::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    height: 4px;
    background: var(--gradient-primary);
}

.plan-card.popular {
    border: 2px solid var(--brand-primary);
    box-shadow: var(--shadow-glow);
}

.plan-card:hover {
    transform: translateY(-8px);
    border-color: var(--border-strong);
    box-shadow: var(--shadow-xl);
}

.popular-badge {
    position: absolute;
    top: -12px;
    left: 50%;
    transform: translateX(-50%);
    background: var(--gradient-primary);
    color: var(--text-primary);
    padding: 6px 20px;
    border-radius: var(--radius-full);
    font-size: var(--font-size-xs);
    font-weight: 700;
    text-transform: uppercase;
    letter-spacing: 0.5px;
    box-shadow: var(--shadow-sm);
}

.plan-header {
    margin-bottom: var(--spacing-lg);
}

.operator-icon {
    width: 56px;
    height: 56px;
    background: var(--gradient-primary);
    border-radius: var(--radius-xl);
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.4rem;
    font-weight: 800;
    color: var(--text-primary);
    margin: 0 auto var(--spacing-sm);
    box-shadow: var(--shadow-sm);
}

.operator-badge {
    display: inline-block;
    padding: 6px 14px;
    background: rgba(99, 102, 241, 0.15);
    color: var(--brand-primary);
    border-radius: var(--radius-full);
    font-size: var(--font-size-xs);
    font-weight: 600;
    margin-bottom: var(--spacing-sm);
}

.plan-name {
    font-size: var(--font-size-xl);
    font-weight: 700;
    color: var(--text-primary);
    margin-bottom: 4px;
}

.plan-subtitle {
    font-size: var(--font-size-sm);
    color: var(--text-muted);
    font-weight: 500;
    margin-bottom: 6px;
}

.plan-desc {
    font-size: var(--font-size-sm);
    color: var(--text-dim);
    margin: 0;
    font-weight: 500;
}

.plan-price {
    margin-bottom: var(--spacing-md);
    display: flex;
    align-items: baseline;
    justify-content: center;
    gap: 6px;
}

.price-label {
    font-size: 1.4rem;
    font-weight: 600;
    color: var(--text-muted);
}

.price-symbol {
    font-size: 1.4rem;
    font-weight: 700;
    color: #ef4444;
}

.price-value {
    font-size: 3rem;
    font-weight: 900;
    line-height: 1;
    color: #ef4444;
}

.price-unit {
    font-size: 1.1rem;
    color: var(--text-muted);
    margin-left: 4px;
    font-weight: 600;
}

.plan-data {
    background: var(--bg-tertiary);
    border-radius: var(--radius-lg);
    padding: var(--spacing-md);
    margin-bottom: var(--spacing-md);
    border: 1px solid var(--border-subtle);
}

.data-value {
    font-size: 1.5rem;
    font-weight: 700;
    color: inherit;
    display: block;
    background: var(--gradient-primary);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.data-label {
    font-size: var(--font-size-sm);
    color: var(--text-muted);
    margin-top: 4px;
    display: block;
    font-weight: 500;
}

.plan-features {
    list-style: none;
    padding: 0;
    margin: 0 0 var(--spacing-lg);
    text-align: left;
}

.plan-features li {
    padding: 10px 0 10px 30px;
    color: var(--text-secondary);
    font-size: var(--font-size-sm);
    position: relative;
    font-weight: 500;
    border-bottom: 1px solid var(--border-subtle);
}

.plan-features li:last-child {
    border-bottom: none;
}

.plan-features li::before {
    content: '✓';
    position: absolute;
    left: 0;
    top: 50%;
    transform: translateY(-50%);
    width: 22px;
    height: 22px;
    border-radius: var(--radius-full);
    background: var(--gradient-secondary);
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 0.9rem;
    font-weight: 700;
    color: var(--text-primary);
}

.plan-btn {
    width: 100%;
    padding: 16px 28px;
    border: none;
    border-radius: var(--radius-xl);
    font-size: var(--font-size-base);
    font-weight: 700;
    color: var(--text-primary);
    cursor: pointer;
    transition: all var(--transition-base);
    box-shadow: var(--shadow-sm);
    background: var(--gradient-primary);
}

.plan-btn:hover {
    transform: translateY(-3px);
    box-shadow: var(--shadow-glow);
}

/* 运营商专属颜色 */
.plan-telecom::before { background: linear-gradient(90deg, #0066cc, #0085ff); }
.plan-telecom .operator-icon { background: linear-gradient(135deg, #0066cc, #0085ff); }
.plan-telecom .operator-badge { background: rgba(0, 102, 204, 0.15); color: #0085ff; }
.plan-telecom .plan-btn { background: linear-gradient(135deg, #0066cc, #0085ff); }

.plan-mobile::before { background: linear-gradient(90deg, #00a54c, #10b981); }
.plan-mobile .operator-icon { background: linear-gradient(135deg, #00a54c, #10b981); }
.plan-mobile .operator-badge { background: rgba(0, 165, 76, 0.15); color: #10b981; }
.plan-mobile .plan-btn { background: linear-gradient(135deg, #00a54c, #10b981); }

.plan-unicom::before { background: linear-gradient(90deg, #1a1a1a, #374151); }
.plan-unicom .operator-icon { background: linear-gradient(135deg, #374151, #1f2937); }
.plan-unicom .operator-badge { background: rgba(55, 65, 81, 0.3); color: #9ca3af; }
.plan-unicom .plan-btn { background: linear-gradient(135deg, #374151, #1f2937); }

.plan-cnmg::before { background: linear-gradient(90deg, #8b5cf6, #722ed1); }
.plan-cnmg .operator-icon { background: var(--gradient-primary); }
.plan-cnmg .operator-badge { background: rgba(139, 92, 246, 0.15); color: #8b5cf6; }
.plan-cnmg .plan-btn { background: var(--gradient-primary); }

/* ==================== 办理流程 ==================== */
.process { 
    padding: var(--spacing-3xl) 0; 
    background: var(--bg-secondary);
    position: relative;
}

.process::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: radial-gradient(ellipse at 50% 0%, rgba(6, 182, 212, 0.05) 0%, transparent 50%);
    pointer-events: none;
}

.process-steps {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
    gap: var(--spacing-xl);
    position: relative;
    z-index: 1;
}

.process-step { 
    text-align: center; 
    position: relative;
    padding: var(--spacing-xl);
    background: var(--gradient-card);
    border: 1px solid var(--border-subtle);
    border-radius: var(--radius-2xl);
    box-shadow: var(--shadow-sm);
    transition: all var(--transition-base);
}

.process-step:hover {
    transform: translateY(-6px);
    box-shadow: var(--shadow-lg);
    border-color: var(--border-medium);
}

.step-number {
    width: 72px;
    height: 72px;
    background: var(--gradient-primary);
    border-radius: var(--radius-xl);
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.8rem;
    font-weight: 800;
    color: var(--text-primary);
    margin: 0 auto var(--spacing-md);
    box-shadow: var(--shadow-glow);
    transition: transform var(--transition-base);
}

.process-step:hover .step-number {
    transform: scale(1.1) rotate(5deg);
}

.step-title {
    font-size: var(--font-size-xl);
    font-weight: 700;
    color: var(--text-primary);
    margin-bottom: var(--spacing-sm);
}

.step-text {
    color: var(--text-muted);
    font-size: var(--font-size-sm);
    line-height: 1.7;
}

/* ==================== 注意事项 ==================== */
.notices {
    padding: var(--spacing-3xl) 0;
    background: var(--bg-primary);
}

.notices-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(340px, 1fr));
    gap: var(--spacing-lg);
}

.notice-card {
    background: var(--gradient-card);
    border-radius: var(--radius-2xl);
    padding: var(--spacing-xl);
    border: 1px solid var(--border-subtle);
    transition: all var(--transition-base);
    box-shadow: var(--shadow-sm);
}

.notice-card:hover {
    box-shadow: var(--shadow-lg);
    transform: translateY(-4px);
    border-color: var(--border-medium);
}

.notice-title {
    font-size: var(--font-size-xl);
    font-weight: 700;
    color: var(--text-primary);
    margin-bottom: var(--spacing-md);
    display: flex;
    align-items: center;
    gap: 12px;
}

.notice-list { list-style: none; }

.notice-list li {
    padding: 12px 0;
    border-bottom: 1px solid var(--border-subtle);
    color: var(--text-secondary);
    font-size: var(--font-size-sm);
}

.notice-list li:last-child { border-bottom: none; }

/* ==================== 常见问题 ==================== */
.faq { 
    padding: var(--spacing-3xl) 0; 
    background: var(--bg-secondary);
}

.faq-list {
    max-width: 850px;
    margin: 0 auto;
}

.faq-item {
    background: var(--gradient-card);
    border-radius: var(--radius-xl);
    margin-bottom: var(--spacing-sm);
    overflow: hidden;
    border: 1px solid var(--border-subtle);
    transition: all var(--transition-base);
    box-shadow: var(--shadow-sm);
}

.faq-item:hover {
    border-color: var(--border-medium);
}

.faq-question {
    padding: 22px 28px;
    font-weight: 600;
    color: var(--text-primary);
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: var(--spacing-md);
    transition: all var(--transition-base);
}

.faq-question::after {
    content: '+';
    font-size: 1.8rem;
    color: var(--brand-primary);
    transition: all var(--transition-base);
    font-weight: 300;
    width: 36px;
    height: 36px;
    display: flex;
    align-items: center;
    justify-content: center;
    background: rgba(99, 102, 241, 0.1);
    border-radius: var(--radius-md);
    flex-shrink: 0;
}

.faq-item.active .faq-question::after { 
    transform: rotate(45deg); 
    background: var(--gradient-primary);
    color: var(--text-primary);
}

.faq-answer {
    padding: 0 28px;
    max-height: 0;
    overflow: hidden;
    transition: all var(--transition-slow);
    color: var(--text-muted);
    line-height: 1.8;
}

.faq-item.active .faq-answer {
    padding: 0 28px 28px;
    max-height: 600px;
}

/* ==================== 城市选择 ==================== */
.cities {
    padding: var(--spacing-3xl) 0;
    background: var(--bg-primary);
}

.cities-hot {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(180px, 1fr));
    gap: var(--spacing-md);
    margin-bottom: var(--spacing-2xl);
}

.city-hot-item {
    background: var(--gradient-card);
    border-radius: var(--radius-xl);
    padding: var(--spacing-lg) var(--spacing-md);
    text-align: center;
    border: 1px solid var(--border-subtle);
    cursor: pointer;
    text-decoration: none;
    color: var(--text-secondary);
    transition: all var(--transition-base);
    box-shadow: var(--shadow-sm);
}

.city-hot-item:hover {
    border-color: var(--brand-primary);
    color: var(--text-primary);
    transform: translateY(-4px);
    box-shadow: var(--shadow-lg);
    background: rgba(99, 102, 241, 0.1);
}

.city-hot-item .city-name {
    font-size: var(--font-size-xl);
    font-weight: 700;
    color: var(--text-primary);
    display: block;
    margin-bottom: 6px;
}

.city-hot-item:hover .city-name {
    color: var(--brand-primary);
}

.city-hot-item .city-tag {
    font-size: var(--font-size-sm);
    color: var(--text-muted);
    font-weight: 500;
}

.cities-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(130px, 1fr));
    gap: var(--spacing-sm);
}

.city-item {
    background: var(--bg-card);
    border-radius: var(--radius-lg);
    padding: var(--spacing-md);
    text-align: center;
    border: 1px solid var(--border-subtle);
    text-decoration: none;
    color: var(--text-secondary);
    font-weight: 500;
    font-size: var(--font-size-sm);
    transition: all var(--transition-base);
}

.city-item:hover {
    border-color: var(--brand-primary);
    color: var(--text-primary);
    background: rgba(99, 102, 241, 0.1);
    transform: translateY(-2px);
}

/* ==================== 信号覆盖 ==================== */
.coverage {
    padding: var(--spacing-3xl) 0;
    background: var(--bg-secondary);
}

.coverage-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
    gap: var(--spacing-lg);
}

.coverage-card {
    padding: var(--spacing-xl);
    background: var(--gradient-card);
    border: 1px solid var(--border-subtle);
    border-radius: var(--radius-2xl);
    box-shadow: var(--shadow-sm);
    transition: all var(--transition-base);
}

.coverage-card:hover {
    transform: translateY(-4px);
    box-shadow: var(--shadow-lg);
    border-color: var(--border-medium);
}

.coverage-title {
    font-size: var(--font-size-xl);
    font-weight: 700;
    color: var(--text-primary);
    margin-bottom: var(--spacing-md);
}

.coverage-list {
    list-style: none;
}

.coverage-list li {
    padding: 10px 0;
    color: var(--text-secondary);
    font-size: var(--font-size-sm);
    position: relative;
    padding-left: 28px;
}

.coverage-list li::before {
    content: '•';
    position: absolute;
    left: 0;
    color: var(--brand-primary);
    font-weight: 700;
    font-size: 1.4rem;
}

/* ==================== 文章/套餐列表 ==================== */
.articles { 
    padding: var(--spacing-3xl) 0; 
    background: var(--bg-primary);
}

.articles-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(400px, 1fr));
    gap: var(--spacing-lg);
}

.card {
    background: var(--gradient-card);
    border-radius: var(--radius-2xl);
    overflow: hidden;
    border: 1px solid var(--border-subtle);
    transition: all var(--transition-base);
    box-shadow: var(--shadow-sm);
    position: relative;
}

.card:hover {
    transform: translateY(-8px);
    box-shadow: var(--shadow-xl);
    border-color: var(--border-medium);
}

.card-image-wrapper {
    position: relative;
    overflow: hidden;
    border-bottom: 1px solid var(--border-subtle);
    aspect-ratio: 1/1;
}

.card-image {
    width: 100%;
    height: 100%;
    object-fit: cover;
    transition: transform var(--transition-base);
}

.card:hover .card-image {
    transform: scale(1.05);
}

.card-body { 
    padding: var(--spacing-lg); 
    display: flex;
    flex-direction: column;
    gap: var(--spacing-md);
}

.card-title {
    font-size: var(--font-size-lg);
    font-weight: 700;
    color: var(--text-primary);
    line-height: 1.5;
    display: -webkit-box;
    -webkit-line-clamp: 2;
    -webkit-box-orient: vertical;
    overflow: hidden;
    margin: 0;
}

.card-title a {
    color: inherit;
    text-decoration: none;
    transition: color var(--transition-base);
}

.card-title a:hover {
    color: var(--brand-primary);
}

.card-stats {
    display: flex;
    gap: var(--spacing-md);
    align-items: center;
}

.stat-item {
    display: flex;
    align-items: center;
    gap: 6px;
    font-size: var(--font-size-sm);
    color: var(--text-muted);
}

.stat-value {
    font-weight: 600;
    color: var(--text-secondary);
}

.stat-divider {
    width: 1px;
    height: 20px;
    background: var(--border-subtle);
}

.card-actions {
    display: flex;
    flex-direction: column;
    gap: var(--spacing-md);
    margin-top: auto;
}

.price-tag {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 8px;
    padding: 12px 18px;
    background: rgba(239, 68, 68, 0.1);
    border-radius: var(--radius-xl);
    border: 1px solid rgba(239, 68, 68, 0.2);
    width: 100%;
}

.price-tag .price-label {
    font-size: var(--font-size-base);
    color: var(--text-muted);
    font-weight: 500;
}

.price-tag .price-value {
    font-size: 1.6rem;
    font-weight: 800;
    color: #ef4444;
}

.card-btn {
    padding: 12px 24px;
    background: var(--gradient-primary);
    color: var(--text-primary);
    border: none;
    border-radius: var(--radius-xl);
    font-weight: 600;
    cursor: pointer;
    transition: all var(--transition-base);
    text-decoration: none;
    font-size: var(--font-size-sm);
    width: 100%;
    text-align: center;
}

.card-btn:hover {
    transform: translateY(-2px);
    box-shadow: var(--shadow-glow);
}

/* ==================== 行动号召 ==================== */
.cta {
    padding: var(--spacing-3xl) 0;
    background: var(--gradient-primary);
    color: var(--text-primary);
    text-align: center;
    position: relative;
    overflow: hidden;
}

.cta::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: radial-gradient(circle, rgba(255,255,255,0.1) 0%, transparent 50%);
}

.cta-title {
    font-size: clamp(2rem, 4vw, 2.6rem);
    font-weight: 800;
    margin-bottom: var(--spacing-md);
    position: relative;
    z-index: 1;
}

.cta-text {
    font-size: var(--font-size-lg);
    opacity: 0.9;
    margin-bottom: var(--spacing-xl);
    max-width: 700px;
    margin-left: auto;
    margin-right: auto;
    line-height: 1.8;
    position: relative;
    z-index: 1;
}

.cta .btn-primary {
    background: var(--text-primary);
    color: var(--brand-primary);
    box-shadow: var(--shadow-md);
    position: relative;
    z-index: 1;
}

.cta .btn-primary:hover {
    transform: translateY(-3px);
    box-shadow: var(--shadow-xl);
}

/* ==================== 底部 ==================== */
.footer {
    background: var(--bg-secondary);
    border-top: 1px solid var(--border-subtle);
    padding: var(--spacing-2xl) 0 var(--spacing-lg);
}

.footer-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
    gap: var(--spacing-xl);
    margin-bottom: var(--spacing-xl);
}

.footer-title {
    font-size: var(--font-size-lg);
    font-weight: 700;
    color: var(--text-primary);
    margin-bottom: var(--spacing-md);
}

.footer-desc {
    color: var(--text-muted);
    font-size: var(--font-size-sm);
    line-height: 1.8;
}

.footer-links {
    list-style: none;
}

.footer-links li {
    margin-bottom: var(--spacing-sm);
}

.footer-links a {
    color: var(--text-secondary);
    text-decoration: none;
    font-size: var(--font-size-sm);
    transition: color var(--transition-base);
}

.footer-links a:hover {
    color: var(--brand-primary);
}

.footer-bottom {
    padding-top: var(--spacing-lg);
    border-top: 1px solid var(--border-subtle);
    text-align: center;
    color: var(--text-dim);
    font-size: var(--font-size-sm);
}

/* ==================== 微信弹窗 ==================== */
.modal-overlay {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: rgba(0, 0, 0, 0.8);
    backdrop-filter: blur(10px);
    display: none;
    align-items: center;
    justify-content: center;
    z-index: 2000;
    padding: var(--spacing-lg);
}

.modal-overlay.active {
    display: flex;
}

.modal {
    background: var(--bg-card);
    border: 1px solid var(--border-medium);
    border-radius: var(--radius-2xl);
    padding: var(--spacing-2xl);
    max-width: 420px;
    width: 100%;
    text-align: center;
    box-shadow: var(--shadow-xl);
    position: relative;
    backdrop-filter: blur(20px);
}

.modal-close {
    position: absolute;
    top: var(--spacing-md);
    right: var(--spacing-md);
    background: none;
    border: none;
    color: var(--text-muted);
    font-size: 1.8rem;
    cursor: pointer;
    width: 40px;
    height: 40px;
    display: flex;
    align-items: center;
    justify-content: center;
    border-radius: var(--radius-md);
    transition: all var(--transition-base);
}

.modal-close:hover {
    background: rgba(255, 255, 255, 0.1);
    color: var(--text-primary);
}

.modal-icon {
    font-size: 3.5rem;
    margin-bottom: var(--spacing-md);
}

.modal-title {
    font-size: var(--font-size-2xl);
    font-weight: 700;
    color: var(--text-primary);
    margin-bottom: var(--spacing-sm);
}

.modal p {
    color: var(--text-muted);
    margin-bottom: var(--spacing-lg);
    font-size: var(--font-size-sm);
}

.modal-wechat {
    display: flex;
    align-items: center;
    gap: var(--spacing-sm);
    background: var(--bg-tertiary);
    border: 1px solid var(--border-subtle);
    border-radius: var(--radius-xl);
    padding: var(--spacing-md);
    margin-bottom: var(--spacing-md);
}

.modal-wechat-id {
    flex: 1;
    font-size: var(--font-size-xl);
    font-weight: 700;
    color: var(--text-primary);
    font-family: monospace;
}

.modal-wechat-copy {
    background: var(--gradient-primary);
    color: var(--text-primary);
    border: none;
    padding: 10px 20px;
    border-radius: var(--radius-md);
    cursor: pointer;
    font-weight: 600;
    transition: all var(--transition-base);
}

.modal-wechat-copy:hover {
    transform: translateY(-2px);
    box-shadow: var(--shadow-sm);
}

.modal-tip {
    color: var(--text-muted);
    font-size: var(--font-size-sm);
    margin: 0;
}

/* ==================== 响应式设计 ==================== */
@media (max-width: 968px) {
    .nav {
        display: none;
    }
    
    .mobile-menu-btn {
        display: block;
    }
    
    .hero h1 {
        font-size: 2.2rem;
    }
    
    .hero-stats {
        gap: var(--spacing-md);
    }
    
    .hero-stat {
        min-width: 120px;
        padding: var(--spacing-sm) var(--spacing-md);
    }
    
    .articles-grid {
        grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    }
}

@media (max-width: 768px) {
    html {
        font-size: 14px;
    }
    
    .hero {
        padding: var(--spacing-2xl) 0;
    }
    
    .hero h1 {
        font-size: 1.8rem;
    }
    
    .hero-subtitle {
        font-size: var(--font-size-base);
    }
    
    .section-title {
        font-size: var(--font-size-xl);
    }
    
    .section-subtitle {
        font-size: var(--font-size-base);
    }
    
    .features-grid,
    .plans-grid,
    .process-steps,
    .notices-grid,
    .coverage-grid,
    .articles-grid {
        grid-template-columns: 1fr;
        gap: var(--spacing-md);
    }
    
    .feature-card,
    .plan-card,
    .process-step,
    .notice-card,
    .coverage-card,
    .card {
        padding: var(--spacing-lg);
    }
    
    .plan-price .price-value {
        font-size: 2.2rem;
    }
    
    .hero-stat {
        min-width: 100px;
        padding: var(--spacing-xs) var(--spacing-sm);
    }
    
    .hero-stat-value {
        font-size: var(--font-size-2xl);
    }
    
    .top-bar span {
        margin: 0 8px;
        font-size: var(--font-size-xs);
    }
    
    .logo-icon {
        width: 40px;
        height: 40px;
        font-size: 1.2rem;
    }
    
    .logo-text {
        font-size: 1.2rem;
    }
    
    .btn {
        padding: 12px 20px;
        font-size: var(--font-size-sm);
    }
    
    .btn-lg {
        padding: 14px 28px;
        font-size: var(--font-size-base);
    }
    
    .card-image-wrapper {
        aspect-ratio: 4/3;
    }
    
    .card-body {
        padding: var(--spacing-md);
    }
    
    .card-title {
        font-size: var(--font-size-base);
    }
    
    .card-actions {
        flex-direction: column;
        gap: var(--spacing-sm);
    }
    
    .price-tag, .card-btn {
        width: 100%;
        padding: 12px 16px;
    }
    
    .price-tag .price-value {
        font-size: 1.3rem;
    }
    
    .stats-grid {
        grid-template-columns: repeat(2, 1fr);
        gap: var(--spacing-md);
    }
    
    .stat-card {
        padding: var(--spacing-md);
    }
    
    .stat-info h3 {
        font-size: 1.4rem;
    }
    
    .stat-icon {
        width: 48px;
        height: 48px;
        font-size: 1.2rem;
    }
    
    .cities-hot {
        grid-template-columns: repeat(2, 1fr);
        gap: var(--spacing-sm);
    }
    
    .city-hot-item {
        padding: var(--spacing-md);
    }
    
    .city-hot-item .city-name {
        font-size: var(--font-size-base);
    }
    
    .cities-grid {
        grid-template-columns: repeat(3, 1fr);
        gap: var(--spacing-xs);
    }
    
    .city-item {
        padding: var(--spacing-sm);
        font-size: var(--font-size-xs);
    }
    
    .faq-question {
        padding: 16px 20px;
        font-size: var(--font-size-sm);
    }
    
    .faq-answer {
        padding: 0 20px;
        font-size: var(--font-size-sm);
    }
    
    .faq-item.active .faq-answer {
        padding: 0 20px 20px;
    }
    
    .footer-grid {
        grid-template-columns: repeat(2, 1fr);
        gap: var(--spacing-lg);
    }
    
    .footer-title {
        font-size: var(--font-size-base);
    }
    
    .modal {
        padding: var(--spacing-lg);
        max-width: 90%;
    }
    
    .modal-title {
        font-size: var(--font-size-xl);
    }
}

@media (max-width: 480px) {
    .container {
        padding: 0 var(--spacing-sm);
    }
    
    html {
        font-size: 13px;
    }
    
    .hero {
        padding: var(--spacing-xl) 0;
    }
    
    .hero h1 {
        font-size: 1.5rem;
    }
    
    .hero-subtitle {
        font-size: var(--font-size-sm);
    }
    
    .hero-badge {
        padding: 8px 14px;
        font-size: var(--font-size-xs);
    }
    
    .hero-stats {
        gap: var(--spacing-sm);
    }
    
    .hero-stat {
        min-width: 80px;
        padding: var(--spacing-xs);
    }
    
    .hero-stat-value {
        font-size: var(--font-size-xl);
    }
    
    .hero-stat-label {
        font-size: var(--font-size-xs);
    }
    
    section {
        padding: var(--spacing-xl) 0;
    }
    
    .section-badge {
        padding: 6px 14px;
        font-size: var(--font-size-xs);
    }
    
    .section-title {
        font-size: var(--font-size-lg);
    }
    
    .section-subtitle {
        font-size: var(--font-size-sm);
    }
    
    .feature-card,
    .plan-card,
    .process-step,
    .notice-card,
    .coverage-card,
    .card {
        padding: var(--spacing-md);
    }
    
    .feature-icon,
    .operator-icon,
    .step-number {
        width: 48px;
        height: 48px;
        font-size: 1.4rem;
    }
    
    .feature-title,
    .plan-name,
    .step-title,
    .notice-title,
    .coverage-title {
        font-size: var(--font-size-base);
    }
    
    .plan-price .price-value {
        font-size: 1.8rem;
    }
    
    .plan-features li {
        padding: 8px 0 8px 24px;
        font-size: var(--font-size-xs);
    }
    
    .plan-btn {
        padding: 12px 20px;
        font-size: var(--font-size-sm);
    }
    
    .stats-grid {
        grid-template-columns: 1fr;
        gap: var(--spacing-sm);
    }
    
    .stat-card {
        flex-direction: column;
        text-align: center;
        gap: var(--spacing-sm);
    }
    
    .stat-info h3 {
        font-size: 1.5rem;
    }
    
    .stat-info p {
        font-size: var(--font-size-xs);
    }
    
    .cities-hot {
        grid-template-columns: 1fr;
    }
    
    .cities-grid {
        grid-template-columns: repeat(2, 1fr);
    }
    
    .faq-question {
        padding: 14px 16px;
        font-size: var(--font-size-xs);
    }
    
    .faq-question::after {
        width: 28px;
        height: 28px;
        font-size: 1.4rem;
    }
    
    .footer-grid {
        grid-template-columns: 1fr;
        gap: var(--spacing-md);
    }
    
    .top-bar {
        padding: 8px 0;
    }
    
    .top-bar span {
        margin: 0 6px;
        font-size: 10px;
    }
    
    .logo-text {
        display: none;
    }
    
    .btn-group {
        flex-direction: column;
        align-items: stretch;
        gap: var(--spacing-sm);
    }
    
    .btn {
        width: 100%;
        justify-content: center;
    }
    
    .modal-title {
        font-size: var(--font-size-lg);
    }
    
    .modal-wechat-id {
        font-size: var(--font-size-lg);
    }
}