/* ===================================
   海边AI培训 - 响应式网站样式表
   =================================== */

/* CSS变量定义 */
:root {
    /* 主题色 */
    --primary: #2563eb;
    --primary-dark: #1d4ed8;
    --primary-light: #3b82f6;
    --secondary: #10b981;
    --accent: #f59e0b;
    
    /* 渐变色 */
    --gradient-primary: linear-gradient(135deg, #2563eb 0%, #10b981 100%);
    --gradient-hero: linear-gradient(135deg, #0f172a 0%, #1e3a5f 50%, #0ea5e9 100%);
    --gradient-waves: linear-gradient(180deg, transparent 0%, rgba(14, 165, 233, 0.1) 100%);
    
    /* 文字颜色 */
    --text-primary: #1e293b;
    --text-secondary: #64748b;
    --text-muted: #94a3b8;
    --text-white: #ffffff;
    
    /* 背景色 */
    --bg-light: #f8fafc;
    --bg-white: #ffffff;
    --bg-dark: #0f172a;
    
    /* 间距 */
    --spacing-xs: 0.25rem;
    --spacing-sm: 0.5rem;
    --spacing-md: 1rem;
    --spacing-lg: 1.5rem;
    --spacing-xl: 2rem;
    --spacing-2xl: 3rem;
    --spacing-3xl: 4rem;
    --spacing-4xl: 6rem;
    
    /* 圆角 */
    --radius-sm: 0.375rem;
    --radius-md: 0.5rem;
    --radius-lg: 1rem;
    --radius-xl: 1.5rem;
    --radius-full: 9999px;
    
    /* 阴影 */
    --shadow-sm: 0 1px 2px 0 rgba(0, 0, 0, 0.05);
    --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.1), 0 2px 4px -1px rgba(0, 0, 0, 0.06);
    --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.1), 0 4px 6px -2px rgba(0, 0, 0, 0.05);
    --shadow-xl: 0 20px 25px -5px rgba(0, 0, 0, 0.1), 0 10px 10px -5px rgba(0, 0, 0, 0.04);
    --shadow-2xl: 0 25px 50px -12px rgba(0, 0, 0, 0.25);
    
    /* 过渡 */
    --transition-fast: 150ms ease;
    --transition-normal: 300ms ease;
    --transition-slow: 500ms ease;
    
    /* 容器 */
    --container-max: 1280px;
    --container-padding: 1.5rem;
}

/* 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: 'PingFang SC', 'Microsoft YaHei', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
    font-size: 16px;
    line-height: 1.6;
    color: var(--text-primary);
    background-color: var(--bg-white);
    overflow-x: hidden;
}

a {
    color: inherit;
    text-decoration: none;
    transition: color var(--transition-fast);
}

ul {
    list-style: none;
}

img {
    max-width: 100%;
    height: auto;
    display: block;
}

button {
    border: none;
    background: none;
    cursor: pointer;
    font-family: inherit;
}

input, select, textarea {
    font-family: inherit;
    font-size: inherit;
}

/* 容器 */
.container {
    max-width: var(--container-max);
    margin: 0 auto;
    padding: 0 var(--container-padding);
}

/* ===================================
   头部导航
   =================================== */
.header {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    z-index: 1000;
    padding: var(--spacing-md) 0;
    transition: all var(--transition-normal);
}

.header.scrolled {
    background: rgba(255, 255, 255, 0.98);
    box-shadow: var(--shadow-md);
    padding: var(--spacing-sm) 0;
}

.nav {
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: var(--spacing-xl);
}

.nav-logo {
    display: flex;
    align-items: center;
    gap: var(--spacing-sm);
    font-size: 1.5rem;
    font-weight: 700;
    color: var(--text-white);
}

.header.scrolled .nav-logo {
    color: var(--primary);
}

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

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

.nav-menu {
    display: flex;
    align-items: center;
    gap: var(--spacing-lg);
}

.nav-link {
    color: rgba(255, 255, 255, 0.9);
    font-weight: 500;
    padding: var(--spacing-sm) var(--spacing-md);
    border-radius: var(--radius-md);
    transition: all var(--transition-fast);
}

.header.scrolled .nav-link {
    color: var(--text-primary);
}

.nav-link:hover,
.nav-link.active {
    background: rgba(255, 255, 255, 0.1);
    color: var(--text-white);
}

.header.scrolled .nav-link:hover,
.header.scrolled .nav-link.active {
    background: var(--primary);
    color: var(--text-white);
}

.nav-cta {
    padding: var(--spacing-sm) var(--spacing-lg);
    background: var(--gradient-primary);
    color: var(--text-white);
    font-weight: 600;
    border-radius: var(--radius-full);
    box-shadow: var(--shadow-md);
    transition: all var(--transition-fast);
}

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

.nav-toggle {
    display: none;
    flex-direction: column;
    gap: 5px;
    padding: var(--spacing-sm);
}

.nav-toggle span {
    width: 24px;
    height: 2px;
    background: var(--text-white);
    transition: all var(--transition-fast);
}

.header.scrolled .nav-toggle span {
    background: var(--text-primary);
}

.nav-toggle.active span:nth-child(1) {
    transform: rotate(45deg) translate(5px, 5px);
}

.nav-toggle.active span:nth-child(2) {
    opacity: 0;
}

.nav-toggle.active span:nth-child(3) {
    transform: rotate(-45deg) translate(5px, -5px);
}

/* ===================================
   按钮样式
   =================================== */
.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: var(--spacing-sm);
    padding: var(--spacing-md) var(--spacing-xl);
    font-weight: 600;
    border-radius: var(--radius-full);
    transition: all var(--transition-fast);
}

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

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

.btn-secondary {
    background: rgba(255, 255, 255, 0.1);
    color: var(--text-white);
    border: 1px solid rgba(255, 255, 255, 0.3);
}

.btn-secondary:hover {
    background: rgba(255, 255, 255, 0.2);
}

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

.btn-outline:hover {
    background: var(--primary);
    color: var(--text-white);
}

.btn-full {
    width: 100%;
}

/* ===================================
   Hero区域
   =================================== */
.hero {
    position: relative;
    min-height: 100vh;
    display: flex;
    align-items: center;
    background: linear-gradient(135deg, #0f172a 0%, #1e3a5f 50%, #0ea5e9 100%);
    overflow: hidden;
    padding: 100px 0 60px;
}

.hero-bg {
    position: absolute;
    inset: 0;
    overflow: hidden;
}

.hero-particles {
    position: absolute;
    inset: 0;
    background-image: 
        radial-gradient(2px 2px at 20px 30px, rgba(255,255,255,0.3), transparent),
        radial-gradient(2px 2px at 40px 70px, rgba(255,255,255,0.2), transparent),
        radial-gradient(1px 1px at 90px 40px, rgba(255,255,255,0.3), transparent),
        radial-gradient(2px 2px at 130px 80px, rgba(255,255,255,0.2), transparent),
        radial-gradient(1px 1px at 160px 30px, rgba(255,255,255,0.4), transparent);
    background-size: 200px 100px;
    animation: particles 20s linear infinite;
}

@keyframes particles {
    0% { background-position: 0 0; }
    100% { background-position: 200px 100px; }
}

.hero .container {
    position: relative;
    z-index: 2;
    width: 100%;
    max-width: 900px;
    margin: 0 auto;
}

.hero-content {
    text-align: center;
}

.hero-badge {
    display: inline-flex;
    align-items: center;
    gap: var(--spacing-sm);
    padding: var(--spacing-sm) var(--spacing-lg);
    background: rgba(255, 255, 255, 0.15);
    border: 1px solid rgba(255, 255, 255, 0.25);
    border-radius: var(--radius-full);
    color: var(--text-white);
    font-size: 0.875rem;
    margin-bottom: var(--spacing-xl);
}

.badge-icon {
    font-size: 1.25rem;
}

.hero-title {
    display: flex;
    flex-direction: column;
    gap: 0.15em;
    font-size: clamp(2rem, 6vw, 3.5rem);
    font-weight: 800;
    line-height: 1.2;
    color: var(--text-white);
    margin-bottom: var(--spacing-xl);
    letter-spacing: -0.02em;
}

.title-line {
    display: block;
}

.title-highlight {
    display: block;
    background: linear-gradient(135deg, #60a5fa 0%, #34d399 100%);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.hero-desc {
    font-size: 1.125rem;
    color: rgba(255, 255, 255, 0.9);
    line-height: 1.8;
    margin-bottom: var(--spacing-2xl);
    max-width: 650px;
    margin-left: auto;
    margin-right: auto;
}

.hero-desc strong {
    color: #fbbf24;
}

.hero-badge {
    display: inline-flex;
    align-items: center;
    gap: var(--spacing-sm);
    padding: var(--spacing-sm) var(--spacing-lg);
    background: rgba(255, 255, 255, 0.1);
    border: 1px solid rgba(255, 255, 255, 0.2);
    border-radius: var(--radius-full);
    color: var(--text-white);
    font-size: 0.875rem;
    margin-bottom: var(--spacing-lg);
}

.badge-icon {
    font-size: 1.25rem;
}

.hero-title {
    display: flex;
    flex-direction: column;
    gap: 0.2em;
    font-size: clamp(1.75rem, 5vw, 3rem);
    font-weight: 800;
    line-height: 1.3;
    color: var(--text-white);
    margin-bottom: var(--spacing-lg);
    letter-spacing: -0.02em;
}

.title-line {
    display: block;
    white-space: nowrap;
}

.title-highlight {
    display: block;
    background: var(--gradient-primary);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
    white-space: nowrap;
}

.hero-desc {
    font-size: 1.125rem;
    color: rgba(255, 255, 255, 0.9);
    line-height: 1.8;
    margin-bottom: var(--spacing-xl);
}

.hero-desc strong {
    color: var(--accent);
}

.hero-stats {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: var(--spacing-lg);
    padding: var(--spacing-xl);
    margin-bottom: var(--spacing-2xl);
    background: rgba(255, 255, 255, 0.05);
    border-radius: var(--radius-xl);
    border: 1px solid rgba(255, 255, 255, 0.1);
}

.stat-item {
    text-align: center;
}

.stat-number {
    font-size: 2rem;
    font-weight: 800;
    color: var(--accent);
}

.stat-unit {
    font-size: 1.25rem;
    font-weight: 700;
    color: var(--accent);
}

.stat-label {
    display: block;
    font-size: 0.875rem;
    color: rgba(255, 255, 255, 0.7);
    margin-top: var(--spacing-xs);
}

.hero-actions {
    display: flex;
    justify-content: center;
    gap: var(--spacing-md);
    margin-bottom: var(--spacing-2xl);
}

.hero-trust {
    display: flex;
    justify-content: center;
    align-items: center;
    flex-wrap: wrap;
    gap: var(--spacing-sm) var(--spacing-lg);
}

.trust-label {
    font-size: 0.875rem;
    color: rgba(255, 255, 255, 0.6);
}

.trust-logos {
    display: flex;
    flex-wrap: wrap;
    gap: var(--spacing-sm);
}

.trust-logo {
    font-size: 0.875rem;
    color: rgba(255, 255, 255, 0.5);
    font-weight: 500;
    padding: var(--spacing-xs) var(--spacing-md);
    background: rgba(255, 255, 255, 0.08);
    border-radius: var(--radius-md);
}

/* ===================================
   通用区块样式
   =================================== */
.section-header {
    text-align: center;
    max-width: 700px;
    margin: 0 auto var(--spacing-3xl);
}

.section-tag {
    display: inline-block;
    padding: var(--spacing-xs) var(--spacing-lg);
    background: linear-gradient(135deg, rgba(37, 99, 235, 0.1) 0%, rgba(16, 185, 129, 0.1) 100%);
    color: var(--primary);
    font-size: 0.875rem;
    font-weight: 600;
    border-radius: var(--radius-full);
    margin-bottom: var(--spacing-md);
}

.section-title {
    font-size: clamp(1.75rem, 4vw, 2.5rem);
    font-weight: 800;
    color: var(--text-primary);
    margin-bottom: var(--spacing-md);
}

.section-desc {
    font-size: 1.125rem;
    color: var(--text-secondary);
    line-height: 1.8;
}

/* ===================================
   课程体系
   =================================== */
.courses {
    padding: var(--spacing-4xl) 0;
    background: var(--bg-light);
}

.course-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: var(--spacing-xl);
}

.course-card {
    position: relative;
    background: var(--bg-white);
    border-radius: var(--radius-xl);
    padding: var(--spacing-xl);
    box-shadow: var(--shadow-md);
    transition: all var(--transition-normal);
    opacity: 0;
    transform: translateY(30px);
}

.course-card.visible {
    opacity: 1;
    transform: translateY(0);
}

.course-card:hover {
    transform: translateY(-10px);
    box-shadow: var(--shadow-xl);
}

.course-badge {
    position: absolute;
    top: var(--spacing-lg);
    right: var(--spacing-lg);
    padding: var(--spacing-xs) var(--spacing-sm);
    background: var(--accent);
    color: var(--text-white);
    font-size: 0.75rem;
    font-weight: 600;
    border-radius: var(--radius-sm);
}

.course-icon {
    font-size: 3rem;
    margin-bottom: var(--spacing-md);
}

.course-title {
    font-size: 1.25rem;
    font-weight: 700;
    color: var(--text-primary);
    margin-bottom: var(--spacing-sm);
}

.course-desc {
    font-size: 0.875rem;
    color: var(--text-secondary);
    line-height: 1.7;
    margin-bottom: var(--spacing-md);
}

.course-tags {
    display: flex;
    flex-wrap: wrap;
    gap: var(--spacing-sm);
    margin-bottom: var(--spacing-md);
}

.course-tags li {
    padding: var(--spacing-xs) var(--spacing-sm);
    background: var(--bg-light);
    color: var(--text-secondary);
    font-size: 0.75rem;
    border-radius: var(--radius-sm);
}

.course-meta {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: var(--spacing-md) 0;
    border-top: 1px solid var(--bg-light);
    margin-bottom: var(--spacing-md);
}

.course-level {
    display: flex;
    align-items: center;
    gap: var(--spacing-sm);
    font-size: 0.875rem;
    color: var(--text-secondary);
}

.level-dot {
    width: 8px;
    height: 8px;
    border-radius: 50%;
}

.level-dot.level-beginner {
    background: var(--secondary);
}

.level-dot.level-advanced {
    background: var(--primary);
}

.level-dot.level-expert {
    background: var(--accent);
}

.course-duration {
    font-size: 0.875rem;
    color: var(--text-muted);
}

.course-footer {
    display: flex;
    align-items: center;
    justify-content: space-between;
}

.course-price {
    font-size: 1.5rem;
    font-weight: 800;
    color: var(--primary);
}

.course-price small {
    font-size: 0.875rem;
    font-weight: 500;
}

.course-btn {
    padding: var(--spacing-sm) var(--spacing-lg);
    background: var(--primary);
    color: var(--text-white);
    font-weight: 600;
    border-radius: var(--radius-full);
    transition: all var(--transition-fast);
}

.course-btn:hover {
    background: var(--primary-dark);
}

.courses-more {
    text-align: center;
    margin-top: var(--spacing-3xl);
}

/* ===================================
   核心优势
   =================================== */
.features {
    padding: var(--spacing-4xl) 0;
    background: var(--bg-white);
}

.features-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: var(--spacing-xl);
    margin-bottom: var(--spacing-4xl);
}

.feature-card {
    padding: var(--spacing-xl);
    background: var(--bg-white);
    border: 1px solid var(--bg-light);
    border-radius: var(--radius-xl);
    transition: all var(--transition-normal);
    opacity: 0;
    transform: translateY(30px);
}

.feature-card.visible {
    opacity: 1;
    transform: translateY(0);
}

.feature-card:hover {
    border-color: var(--primary);
    box-shadow: var(--shadow-lg);
}

.feature-icon {
    width: 64px;
    height: 64px;
    display: flex;
    align-items: center;
    justify-content: center;
    background: linear-gradient(135deg, rgba(37, 99, 235, 0.1) 0%, rgba(16, 185, 129, 0.1) 100%);
    border-radius: var(--radius-lg);
    margin-bottom: var(--spacing-lg);
    color: var(--primary);
}

.feature-title {
    font-size: 1.25rem;
    font-weight: 700;
    color: var(--text-primary);
    margin-bottom: var(--spacing-sm);
}

.feature-desc {
    font-size: 0.9375rem;
    color: var(--text-secondary);
    line-height: 1.7;
}

/* 学习路径 */
.learning-path {
    background: var(--gradient-hero);
    border-radius: var(--radius-xl);
    padding: var(--spacing-3xl);
}

.path-title {
    text-align: center;
    font-size: 1.5rem;
    font-weight: 700;
    color: var(--text-white);
    margin-bottom: var(--spacing-2xl);
}

.path-timeline {
    display: flex;
    align-items: center;
    justify-content: space-between;
}

.path-step {
    flex: 1;
    text-align: center;
    padding: var(--spacing-lg);
}

.step-number {
    width: 48px;
    height: 48px;
    margin: 0 auto var(--spacing-md);
    display: flex;
    align-items: center;
    justify-content: center;
    background: var(--primary);
    color: var(--text-white);
    font-size: 1.25rem;
    font-weight: 700;
    border-radius: 50%;
    border: 3px solid var(--secondary);
}

.step-content h4 {
    font-size: 1.125rem;
    font-weight: 700;
    color: var(--text-white);
    margin-bottom: var(--spacing-xs);
}

.step-content p {
    font-size: 0.875rem;
    color: rgba(255, 255, 255, 0.8);
    margin-bottom: var(--spacing-sm);
}

.step-duration {
    display: inline-block;
    padding: var(--spacing-xs) var(--spacing-sm);
    background: rgba(255, 255, 255, 0.1);
    color: var(--secondary);
    font-size: 0.75rem;
    border-radius: var(--radius-full);
}

.path-arrow {
    width: 40px;
    height: 2px;
    background: linear-gradient(90deg, var(--primary), var(--secondary));
    position: relative;
}

.path-arrow::after {
    content: '→';
    position: absolute;
    right: -5px;
    top: 50%;
    transform: translateY(-50%);
    color: var(--secondary);
    font-size: 1.25rem;
}

/* ===================================
   师资团队
   =================================== */
.teachers {
    padding: var(--spacing-4xl) 0;
    background: var(--bg-light);
}

.teachers-grid {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: var(--spacing-xl);
}

.teacher-card {
    background: var(--bg-white);
    border-radius: var(--radius-xl);
    padding: var(--spacing-xl);
    text-align: center;
    box-shadow: var(--shadow-md);
    transition: all var(--transition-normal);
    opacity: 0;
    transform: translateY(30px);
}

.teacher-card.visible {
    opacity: 1;
    transform: translateY(0);
}

.teacher-card:hover {
    transform: translateY(-10px);
    box-shadow: var(--shadow-xl);
}

.teacher-avatar {
    width: 100px;
    height: 100px;
    margin: 0 auto var(--spacing-md);
    background: var(--gradient-primary);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 3rem;
}

.teacher-name {
    font-size: 1.25rem;
    font-weight: 700;
    color: var(--text-primary);
    margin-bottom: var(--spacing-xs);
}

.teacher-title {
    font-size: 0.875rem;
    color: var(--primary);
    font-weight: 600;
    margin-bottom: var(--spacing-xs);
}

.teacher-company {
    font-size: 0.875rem;
    color: var(--text-muted);
    margin-bottom: var(--spacing-md);
}

.teacher-desc {
    font-size: 0.875rem;
    color: var(--text-secondary);
    line-height: 1.7;
    margin-bottom: var(--spacing-md);
}

.teacher-tags {
    display: flex;
    flex-wrap: wrap;
    justify-content: center;
    gap: var(--spacing-xs);
}

.teacher-tags li {
    padding: var(--spacing-xs) var(--spacing-sm);
    background: var(--bg-light);
    color: var(--text-secondary);
    font-size: 0.75rem;
    border-radius: var(--radius-sm);
}

/* ===================================
   学员案例
   =================================== */
.cases {
    padding: var(--spacing-4xl) 0;
    background: var(--bg-white);
}

.cases-grid {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: var(--spacing-xl);
    margin-bottom: var(--spacing-3xl);
}

.case-card {
    background: var(--bg-white);
    border: 1px solid var(--bg-light);
    border-radius: var(--radius-xl);
    padding: var(--spacing-xl);
    transition: all var(--transition-normal);
    opacity: 0;
    transform: translateY(30px);
}

.case-card.visible {
    opacity: 1;
    transform: translateY(0);
}

.case-card:hover {
    border-color: var(--primary);
    box-shadow: var(--shadow-lg);
}

.case-header {
    display: flex;
    align-items: center;
    gap: var(--spacing-md);
    margin-bottom: var(--spacing-md);
}

.case-avatar {
    width: 56px;
    height: 56px;
    background: var(--gradient-primary);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.5rem;
}

.case-info {
    flex: 1;
}

.case-info h4 {
    font-size: 1.125rem;
    font-weight: 700;
    color: var(--text-primary);
}

.case-info p {
    font-size: 0.875rem;
    color: var(--text-secondary);
}

.case-salary {
    padding: var(--spacing-xs) var(--spacing-md);
    background: linear-gradient(135deg, rgba(16, 185, 129, 0.1) 0%, rgba(37, 99, 235, 0.1) 100%);
    color: var(--secondary);
    font-size: 0.875rem;
    font-weight: 700;
    border-radius: var(--radius-full);
}

.case-tags {
    display: flex;
    gap: var(--spacing-md);
    margin-bottom: var(--spacing-md);
}

.case-tags span {
    padding: var(--spacing-xs) var(--spacing-sm);
    background: var(--bg-light);
    color: var(--text-secondary);
    font-size: 0.75rem;
    border-radius: var(--radius-sm);
}

.case-quote {
    font-size: 0.9375rem;
    color: var(--text-secondary);
    line-height: 1.8;
    font-style: italic;
    border-left: 3px solid var(--primary);
    padding-left: var(--spacing-md);
}

/* 合作企业 */
.employers {
    text-align: center;
}

.employers-title {
    font-size: 1.25rem;
    font-weight: 700;
    color: var(--text-primary);
    margin-bottom: var(--spacing-xl);
}

.employers-logos {
    display: flex;
    flex-wrap: wrap;
    justify-content: center;
    gap: var(--spacing-xl);
}

.employer-logo {
    display: flex;
    align-items: center;
    gap: var(--spacing-sm);
    padding: var(--spacing-md) var(--spacing-xl);
    background: var(--bg-light);
    border-radius: var(--radius-lg);
    transition: all var(--transition-fast);
}

.employer-logo:hover {
    background: var(--bg-white);
    box-shadow: var(--shadow-md);
    transform: translateY(-3px);
}

.employer-logo .logo-icon {
    font-size: 1.5rem;
}

.employer-logo span:last-child {
    font-weight: 600;
    color: var(--text-primary);
}

/* ===================================
   常见问题
   =================================== */
.faq {
    padding: var(--spacing-4xl) 0;
    background: var(--bg-light);
}

.faq-list {
    max-width: 800px;
    margin: 0 auto;
}

.faq-item {
    background: var(--bg-white);
    border-radius: var(--radius-lg);
    margin-bottom: var(--spacing-md);
    overflow: hidden;
    box-shadow: var(--shadow-sm);
}

.faq-question {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: var(--spacing-lg) var(--spacing-xl);
    cursor: pointer;
    font-weight: 600;
    color: var(--text-primary);
    list-style: none;
}

.faq-question::-webkit-details-marker {
    display: none;
}

.faq-question span:first-child {
    flex: 1;
}

.faq-icon {
    font-size: 1.5rem;
    color: var(--primary);
    transition: transform var(--transition-fast);
}

.faq-item[open] .faq-icon {
    transform: rotate(45deg);
}

.faq-answer {
    padding: 0 var(--spacing-xl) var(--spacing-lg);
}

.faq-answer p {
    font-size: 0.9375rem;
    color: var(--text-secondary);
    line-height: 1.8;
}

/* ===================================
   免费试听
   =================================== */
.free-trial {
    padding: var(--spacing-4xl) 0;
    background: var(--gradient-hero);
}

.trial-content {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: var(--spacing-3xl);
    align-items: center;
}

.trial-tag {
    display: inline-block;
    padding: var(--spacing-xs) var(--spacing-lg);
    background: var(--accent);
    color: var(--text-white);
    font-size: 0.875rem;
    font-weight: 700;
    border-radius: var(--radius-full);
    margin-bottom: var(--spacing-md);
}

.trial-title {
    font-size: 2rem;
    font-weight: 800;
    color: var(--text-white);
    margin-bottom: var(--spacing-md);
}

.trial-desc {
    font-size: 1.125rem;
    color: rgba(255, 255, 255, 0.9);
    margin-bottom: var(--spacing-xl);
}

.trial-list {
    display: flex;
    flex-direction: column;
    gap: var(--spacing-md);
}

.trial-list li {
    display: flex;
    align-items: center;
    gap: var(--spacing-md);
    color: var(--text-white);
}

.check-icon {
    width: 24px;
    height: 24px;
    background: var(--secondary);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 0.75rem;
    color: var(--text-white);
}

.form-box {
    background: var(--bg-white);
    border-radius: var(--radius-xl);
    padding: var(--spacing-2xl);
    box-shadow: var(--shadow-2xl);
}

.form-title {
    font-size: 1.5rem;
    font-weight: 700;
    color: var(--text-primary);
    text-align: center;
    margin-bottom: var(--spacing-xl);
}

.form-group {
    margin-bottom: var(--spacing-lg);
}

.form-group input,
.form-group select {
    width: 100%;
    padding: var(--spacing-md) var(--spacing-lg);
    border: 1px solid var(--bg-light);
    border-radius: var(--radius-lg);
    font-size: 1rem;
    transition: all var(--transition-fast);
}

.form-group input:focus,
.form-group select:focus {
    outline: none;
    border-color: var(--primary);
    box-shadow: 0 0 0 3px rgba(37, 99, 235, 0.1);
}

.form-note {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: var(--spacing-sm);
    margin-top: var(--spacing-md);
    font-size: 0.875rem;
    color: var(--text-muted);
}

/* ===================================
   联系我们
   =================================== */
.contact {
    padding: var(--spacing-4xl) 0;
    background: var(--bg-white);
}

.contact-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: var(--spacing-3xl);
}

.contact-title {
    font-size: 2rem;
    font-weight: 800;
    color: var(--text-primary);
    margin-bottom: var(--spacing-md);
}

.contact-desc {
    font-size: 1.125rem;
    color: var(--text-secondary);
    margin-bottom: var(--spacing-xl);
}

.contact-list {
    display: flex;
    flex-direction: column;
    gap: var(--spacing-lg);
    margin-bottom: var(--spacing-xl);
}

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

.contact-icon {
    width: 48px;
    height: 48px;
    display: flex;
    align-items: center;
    justify-content: center;
    background: linear-gradient(135deg, rgba(37, 99, 235, 0.1) 0%, rgba(16, 185, 129, 0.1) 100%);
    border-radius: var(--radius-lg);
    color: var(--primary);
}

.contact-text {
    display: flex;
    flex-direction: column;
}

.contact-text .label {
    font-size: 0.875rem;
    color: var(--text-muted);
}

.contact-text a,
.contact-text span:last-child {
    font-size: 1rem;
    color: var(--text-primary);
    font-weight: 500;
}

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

.contact-social h4 {
    font-size: 1rem;
    font-weight: 600;
    color: var(--text-primary);
    margin-bottom: var(--spacing-md);
}

.social-links {
    display: flex;
    gap: var(--spacing-md);
}

.social-link {
    width: 44px;
    height: 44px;
    display: flex;
    align-items: center;
    justify-content: center;
    background: var(--bg-light);
    border-radius: var(--radius-lg);
    color: var(--text-secondary);
    transition: all var(--transition-fast);
}

.social-link:hover {
    background: var(--primary);
    color: var(--text-white);
}

.contact-map {
    position: relative;
}

.map-placeholder {
    width: 100%;
    height: 100%;
    min-height: 400px;
    background: linear-gradient(135deg, var(--bg-light) 0%, var(--primary) 100%);
    border-radius: var(--radius-xl);
    display: flex;
    align-items: center;
    justify-content: center;
}

.map-info {
    text-align: center;
    color: var(--text-white);
}

.map-icon {
    font-size: 4rem;
    margin-bottom: var(--spacing-md);
}

.map-info p {
    font-size: 1.25rem;
    font-weight: 600;
    margin-bottom: var(--spacing-md);
}

.map-link {
    color: var(--text-white);
    font-weight: 500;
    text-decoration: underline;
}

/* ===================================
   页脚
   =================================== */
.footer {
    background: var(--bg-dark);
    color: var(--text-white);
    padding: var(--spacing-4xl) 0 var(--spacing-xl);
}

.footer-grid {
    display: grid;
    grid-template-columns: 1.5fr 1fr 1fr 1fr 1.5fr;
    gap: var(--spacing-2xl);
    margin-bottom: var(--spacing-3xl);
}

.footer-logo {
    display: flex;
    align-items: center;
    gap: var(--spacing-sm);
    margin-bottom: var(--spacing-md);
}

.footer-logo .logo-icon {
    font-size: 2rem;
}

.footer-logo .logo-text {
    font-size: 1.25rem;
    font-weight: 700;
}

.footer-desc {
    font-size: 0.875rem;
    color: rgba(255, 255, 255, 0.7);
    line-height: 1.7;
    margin-bottom: var(--spacing-sm);
}

.footer-slogan {
    font-size: 1rem;
    font-weight: 600;
    color: var(--accent);
}

.footer-title {
    font-size: 1rem;
    font-weight: 700;
    margin-bottom: var(--spacing-lg);
}

.footer-links {
    display: flex;
    flex-direction: column;
    gap: var(--spacing-sm);
}

.footer-links a {
    font-size: 0.875rem;
    color: rgba(255, 255, 255, 0.7);
    transition: color var(--transition-fast);
}

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

.footer-contact-item {
    display: flex;
    align-items: center;
    gap: var(--spacing-sm);
    margin-bottom: var(--spacing-sm);
    font-size: 0.875rem;
    color: rgba(255, 255, 255, 0.7);
}

.footer-qrcode {
    margin-top: var(--spacing-lg);
}

.qrcode-box {
    display: inline-flex;
    flex-direction: column;
    align-items: center;
    gap: var(--spacing-xs);
    padding: var(--spacing-md);
    background: rgba(255, 255, 255, 0.1);
    border-radius: var(--radius-lg);
}

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

.qrcode-box span:last-child {
    font-size: 0.75rem;
    color: rgba(255, 255, 255, 0.7);
}

.footer-bottom {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding-top: var(--spacing-xl);
    border-top: 1px solid rgba(255, 255, 255, 0.1);
}

.footer-legal {
    display: flex;
    align-items: center;
    gap: var(--spacing-lg);
    font-size: 0.875rem;
    color: rgba(255, 255, 255, 0.5);
}

.footer-legal a {
    color: rgba(255, 255, 255, 0.5);
}

.footer-legal a:hover {
    color: var(--primary-light);
}

.footer-cert {
    display: flex;
    gap: var(--spacing-md);
}

.cert-badge {
    padding: var(--spacing-xs) var(--spacing-md);
    background: rgba(255, 255, 255, 0.1);
    font-size: 0.75rem;
    color: rgba(255, 255, 255, 0.7);
    border-radius: var(--radius-sm);
}

/* ===================================
   悬浮组件
   =================================== */
.back-to-top {
    position: fixed;
    bottom: var(--spacing-xl);
    right: var(--spacing-xl);
    width: 48px;
    height: 48px;
    background: var(--primary);
    color: var(--text-white);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    box-shadow: var(--shadow-lg);
    opacity: 0;
    visibility: hidden;
    transform: translateY(20px);
    transition: all var(--transition-normal);
    z-index: 999;
}

.back-to-top.show {
    opacity: 1;
    visibility: visible;
    transform: translateY(0);
}

.back-to-top:hover {
    background: var(--primary-dark);
    transform: translateY(-3px);
}

.consult-btn {
    position: fixed;
    bottom: var(--spacing-xl);
    right: var(--spacing-xl);
    padding: var(--spacing-md) var(--spacing-xl);
    background: var(--gradient-primary);
    color: var(--text-white);
    font-weight: 600;
    border-radius: var(--radius-full);
    box-shadow: var(--shadow-xl);
    display: flex;
    align-items: center;
    gap: var(--spacing-sm);
    z-index: 998;
    animation: bounce 2s ease-in-out infinite;
}

.consult-btn:hover {
    transform: scale(1.05);
}

@keyframes bounce {
    0%, 100% {
        transform: translateY(0);
    }
    50% {
        transform: translateY(-5px);
    }
}

.consult-popup {
    position: fixed;
    inset: 0;
    background: rgba(0, 0, 0, 0.5);
    display: flex;
    align-items: center;
    justify-content: center;
    z-index: 1001;
    opacity: 0;
    visibility: hidden;
    transition: all var(--transition-normal);
}

.consult-popup.show {
    opacity: 1;
    visibility: visible;
}

.consult-popup .popup-content {
    background: var(--bg-white);
    border-radius: var(--radius-xl);
    padding: var(--spacing-2xl);
    max-width: 400px;
    width: 90%;
    transform: scale(0.9);
    transition: transform var(--transition-normal);
}

.consult-popup.show .popup-content {
    transform: scale(1);
}

.popup-close {
    position: absolute;
    top: var(--spacing-md);
    right: var(--spacing-md);
    width: 32px;
    height: 32px;
    background: var(--bg-light);
    border-radius: 50%;
    font-size: 1.5rem;
    color: var(--text-secondary);
    display: flex;
    align-items: center;
    justify-content: center;
}

.popup-close:hover {
    background: var(--bg-dark);
    color: var(--text-white);
}

.popup-content h3 {
    font-size: 1.5rem;
    font-weight: 700;
    color: var(--text-primary);
    text-align: center;
    margin-bottom: var(--spacing-sm);
}

.popup-content p {
    font-size: 0.875rem;
    color: var(--text-secondary);
    text-align: center;
    margin-bottom: var(--spacing-xl);
}

.popup-form {
    display: flex;
    flex-direction: column;
    gap: var(--spacing-md);
}

.popup-form input {
    width: 100%;
    padding: var(--spacing-md);
    border: 1px solid var(--bg-light);
    border-radius: var(--radius-lg);
}

.popup-form input:focus {
    outline: none;
    border-color: var(--primary);
}

/* ===================================
   响应式设计
   =================================== */

/* 平板设备 */
@media (max-width: 1024px) {
    :root {
        --container-padding: 1.25rem;
    }

    .hero .container {
        flex-direction: column;
        text-align: center;
    }

    .hero-content {
        max-width: 100%;
    }

    .hero-stats {
        grid-template-columns: repeat(2, 1fr);
    }

    .hero-trust {
        justify-content: center;
        flex-wrap: wrap;
    }

    .hero-visual {
        display: none;
    }

    .course-grid {
        grid-template-columns: repeat(2, 1fr);
    }

    .features-grid {
        grid-template-columns: repeat(2, 1fr);
    }

    .path-timeline {
        flex-direction: column;
        gap: var(--spacing-lg);
    }

    .path-arrow {
        width: 2px;
        height: 30px;
        background: linear-gradient(180deg, var(--primary), var(--secondary));
    }

    .path-arrow::after {
        content: '↓';
        right: 50%;
        top: auto;
        bottom: -5px;
        transform: translateX(50%);
    }

    .teachers-grid {
        grid-template-columns: repeat(2, 1fr);
    }

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

    .trial-content {
        grid-template-columns: 1fr;
        text-align: center;
    }

    .trial-list li {
        justify-content: center;
    }

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

    .footer-grid {
        grid-template-columns: repeat(2, 1fr);
    }
}

/* 手机设备 */
@media (max-width: 768px) {
    :root {
        --container-padding: 1rem;
    }

    .nav-menu {
        position: fixed;
        top: 0;
        left: 0;
        right: 0;
        bottom: 0;
        background: var(--bg-dark);
        flex-direction: column;
        justify-content: center;
        align-items: center;
        gap: var(--spacing-xl);
        opacity: 0;
        visibility: hidden;
        transition: all var(--transition-normal);
    }

    .nav-menu.active {
        opacity: 1;
        visibility: visible;
    }

    .nav-menu .nav-link {
        font-size: 1.25rem;
        color: #ffffff !important;
    }

    .nav-menu .nav-link:hover,
    .nav-menu .nav-link.active {
        color: #ffffff !important;
        background: rgba(255, 255, 255, 0.1);
    }

    .nav-toggle {
        display: flex;
        z-index: 1001;
    }

    .nav-cta {
        display: none;
    }

    .hero {
        padding: 100px 0 60px;
        min-height: auto;
    }

    .hero-content {
        text-align: center;
    }

    .hero-badge {
        justify-content: center;
        font-size: 0.75rem;
        padding: var(--spacing-xs) var(--spacing-md);
    }

    .hero-title {
        font-size: 1.5rem;
        line-height: 1.4;
        gap: 0.1em;
    }

    .hero-title .title-line,
    .hero-title .title-highlight {
        white-space: normal;
    }

    .hero-desc {
        font-size: 0.9375rem;
        line-height: 1.7;
    }

    .hero-stats {
        grid-template-columns: repeat(2, 1fr);
        gap: var(--spacing-md);
    }

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

    .hero-actions {
        flex-direction: column;
    }

    .btn {
        width: 100%;
    }

    .section-title {
        font-size: 1.5rem;
    }

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

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

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

    .employers-logos {
        gap: var(--spacing-md);
    }

    .employer-logo {
        padding: var(--spacing-sm) var(--spacing-md);
    }

    .footer-grid {
        grid-template-columns: 1fr;
        text-align: center;
    }

    .footer-logo {
        justify-content: center;
    }

    .footer-links {
        align-items: center;
    }

    .footer-contact-item {
        justify-content: center;
    }

    .footer-bottom {
        flex-direction: column;
        gap: var(--spacing-md);
    }

    .footer-legal {
        flex-direction: column;
        gap: var(--spacing-sm);
    }

    .consult-btn span:last-child {
        display: none;
    }

    .consult-btn {
        padding: var(--spacing-md);
        border-radius: 50%;
        bottom: var(--spacing-md);
        right: var(--spacing-md);
    }

    .back-to-top {
        bottom: var(--spacing-md);
        right: calc(var(--spacing-md) + 70px);
    }
}

/* 小屏幕手机 */
@media (max-width: 480px) {
    .hero-badge {
        font-size: 0.7rem;
        padding: var(--spacing-xs) var(--spacing-sm);
    }

    .hero-title {
        font-size: 1.35rem;
        letter-spacing: -0.01em;
    }

    .hero-desc {
        font-size: 0.875rem;
    }

    .stat-number {
        font-size: 1.25rem;
    }

    .stat-label {
        font-size: 0.75rem;
    }

    .trust-logos {
        flex-wrap: wrap;
        justify-content: center;
    }

    .course-card {
        padding: var(--spacing-lg);
    }

    .feature-icon {
        width: 48px;
        height: 48px;
    }

    .form-box {
        padding: var(--spacing-lg);
    }

    .contact-list {
        gap: var(--spacing-md);
    }

    .contact-icon {
        width: 40px;
        height: 40px;
    }

    .social-links {
        justify-content: center;
    }
}

/* 动画优化 - 减少动画提升性能 */
@media (prefers-reduced-motion: reduce) {
    *,
    *::before,
    *::after {
        animation-duration: 0.01ms !important;
        animation-iteration-count: 1 !important;
        transition-duration: 0.01ms !important;
    }
}

/* 打印样式 */
@media print {
    .header,
    .back-to-top,
    .consult-btn,
    .consult-popup,
    .hero-visual {
        display: none !important;
    }

    .hero {
        background: white !important;
        color: black !important;
    }

    .hero-title,
    .section-title {
        color: black !important;
    }
}