/* ========================================
   挂连网络科技 - 液态玻璃设计风格
   Liquid Glass Design System
   ======================================== */

:root {
    /* 核心色彩系统 */
    --bg: #070A1C;
    --ink: #F2F5FF;
    --muted: #AAB6DC;
    --pink: #FF2E88;
    --violet: #7C4DFF;
    --cyan: #00E0FF;
    --mint: #38FFC3;
    
    /* 玻璃拟态变量 */
    --glass: rgba(255,255,255,.09);
    --glass-hi: rgba(255,255,255,.16);
    --border-color: rgba(255,255,255,.26);
    
    /* 圆角规范 - 18px 为关键视觉指纹 */
    --radius: 18px;
    --radius-sm: 12px;
    --radius-lg: 24px;
    
    /* 间距系统 - 8px 模数 */
    --space-xs: 4px;
    --space-sm: 8px;
    --space-md: 16px;
    --space-lg: 24px;
    --space-xl: 32px;
    --space-2xl: 48px;
    --space-3xl: 64px;
    
    /* 字体系统 - Outfit */
    --font-family: 'Outfit', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
    --font-size-xs: 13px;
    --font-size-sm: 14px;
    --font-size-base: 16px;
    --font-size-lg: 18px;
    --font-size-xl: 24px;
    --font-size-2xl: 32px;
    --font-size-3xl: clamp(2rem, 5vw, 4rem);
    
    /* 字重 */
    --font-weight-normal: 400;
    --font-weight-medium: 500;
    --font-weight-bold: 700;
    --font-weight-black: 800;
    
    /* 行高 */
    --line-height-tight: 1.1;
    --line-height-normal: 1.6;
    --line-height-relaxed: 1.8;
}

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

html {
    scroll-behavior: smooth;
    font-size: 16px;
}

body {
    font-family: var(--font-family);
    font-size: var(--font-size-base);
    line-height: var(--line-height-normal);
    color: var(--ink);
    background: var(--bg);
    min-height: 100vh;
    overflow-x: hidden;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

/* 背景装饰 - 液态渐变 */
body::before {
    content: '';
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: 
        radial-gradient(ellipse 80% 50% at 20% 20%, rgba(124, 77, 255, 0.15) 0%, transparent 50%),
        radial-gradient(ellipse 60% 40% at 80% 80%, rgba(0, 224, 255, 0.12) 0%, transparent 50%),
        radial-gradient(ellipse 50% 30% at 50% 50%, rgba(255, 46, 136, 0.08) 0%, transparent 50%);
    pointer-events: none;
    z-index: 0;
    animation: bgMorph 20s ease-in-out infinite;
}

@keyframes bgMorph {
    0%, 100% { opacity: 1; transform: scale(1); }
    50% { opacity: 0.8; transform: scale(1.05); }
}

/* ========================================
   容器与布局
   ======================================== */
.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 var(--space-lg);
    position: relative;
    z-index: 1;
}

.section {
    padding: var(--space-3xl) 0;
}

/* ========================================
   玻璃拟态卡片
   ======================================== */
.glass-card {
    background: var(--glass);
    backdrop-filter: blur(20px) saturate(180%);
    -webkit-backdrop-filter: blur(20px) saturate(180%);
    border: 1px solid var(--border-color);
    border-radius: var(--radius);
    padding: var(--space-lg);
    transition: all 0.4s cubic-bezier(0.4, 0, 0.2, 1);
    position: relative;
    overflow: hidden;
}

.glass-card::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    height: 1px;
    background: linear-gradient(90deg, 
        transparent 0%, 
        rgba(255,255,255,0.4) 50%, 
        transparent 100%);
    opacity: 0.6;
}

.glass-card:hover {
    background: var(--glass-hi);
    border-color: rgba(255,255,255,0.35);
    transform: translateY(-4px);
    box-shadow: 
        0 20px 40px rgba(0,0,0,0.3),
        0 0 60px rgba(124, 77, 255, 0.1);
}

/* ========================================
   顶部导航栏
   ======================================== */
.navbar {
    position: sticky;
    top: 0;
    z-index: 1000;
    background: rgba(7, 10, 28, 0.8);
    backdrop-filter: blur(20px) saturate(180%);
    -webkit-backdrop-filter: blur(20px) saturate(180%);
    border-bottom: 1px solid var(--border-color);
}

.navbar .container {
    display: flex;
    align-items: center;
    justify-content: space-between;
    height: 72px;
}

.navbar-brand {
    display: flex;
    align-items: center;
    gap: var(--space-sm);
    text-decoration: none;
    color: var(--ink);
    font-weight: var(--font-weight-bold);
    font-size: var(--font-size-lg);
}

.navbar-brand svg {
    width: 32px;
    height: 32px;
}

.navbar-menu {
    display: flex;
    align-items: center;
    gap: var(--space-xl);
    list-style: none;
}

.navbar-menu a {
    color: var(--muted);
    text-decoration: none;
    font-size: var(--font-size-sm);
    font-weight: var(--font-weight-medium);
    transition: color 0.3s ease;
    position: relative;
}

.navbar-menu a:hover,
.navbar-menu a.active {
    color: var(--ink);
}

.navbar-menu a::after {
    content: '';
    position: absolute;
    bottom: -4px;
    left: 0;
    width: 0;
    height: 2px;
    background: linear-gradient(90deg, var(--violet), var(--cyan));
    transition: width 0.3s ease;
}

.navbar-menu a:hover::after,
.navbar-menu a.active::after {
    width: 100%;
}

.navbar-cta {
    display: flex;
    align-items: center;
    gap: var(--space-md);
}

/* 移动端菜单按钮 */
.menu-toggle {
    display: none;
    background: none;
    border: none;
    color: var(--ink);
    cursor: pointer;
    padding: var(--space-sm);
}

.menu-toggle svg {
    width: 24px;
    height: 24px;
}

/* ========================================
   按钮系统
   ======================================== */
.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: var(--space-sm);
    padding: 12px 24px;
    border-radius: var(--radius);
    font-family: var(--font-family);
    font-size: var(--font-size-sm);
    font-weight: var(--font-weight-medium);
    text-decoration: none;
    cursor: pointer;
    border: none;
    transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
    min-height: 44px;
    white-space: nowrap;
}

.btn-primary {
    background: linear-gradient(135deg, var(--violet) 0%, var(--pink) 100%);
    color: var(--ink);
    box-shadow: 0 4px 20px rgba(124, 77, 255, 0.4);
}

.btn-primary:hover {
    transform: translateY(-2px);
    box-shadow: 0 8px 30px rgba(124, 77, 255, 0.6);
}

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

.btn-secondary {
    background: var(--glass);
    color: var(--ink);
    border: 1px solid var(--border-color);
    backdrop-filter: blur(10px);
}

.btn-secondary:hover {
    background: var(--glass-hi);
    border-color: rgba(255,255,255,0.4);
}

.btn-ghost {
    background: transparent;
    color: var(--muted);
    padding: 8px 16px;
}

.btn-ghost:hover {
    color: var(--ink);
    background: var(--glass);
}

.btn:disabled {
    opacity: 0.5;
    cursor: not-allowed;
    transform: none !important;
}

/* ========================================
   Hero 区域
   ======================================== */
.hero {
    min-height: 80vh;
    display: flex;
    align-items: center;
    padding: var(--space-3xl) 0;
    position: relative;
}

.hero-content {
    max-width: 720px;
}

.hero-eyebrow {
    display: inline-block;
    font-size: var(--font-size-xs);
    font-weight: var(--font-weight-medium);
    letter-spacing: 0.15em;
    text-transform: uppercase;
    color: var(--cyan);
    margin-bottom: var(--space-md);
    padding: 6px 16px;
    background: var(--glass);
    border: 1px solid var(--border-color);
    border-radius: 100px;
}

.hero-title {
    font-size: var(--font-size-3xl);
    font-weight: var(--font-weight-black);
    line-height: var(--line-height-tight);
    margin-bottom: var(--space-md);
    background: linear-gradient(135deg, var(--ink) 0%, var(--cyan) 100%);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.hero-subtitle {
    font-size: var(--font-size-lg);
    color: var(--muted);
    line-height: var(--line-height-relaxed);
    margin-bottom: var(--space-xl);
    max-width: 34em;
}

.hero-actions {
    display: flex;
    gap: var(--space-md);
    flex-wrap: wrap;
}

/* Hero 装饰元素 */
.hero-decoration {
    position: absolute;
    right: 0;
    top: 50%;
    transform: translateY(-50%);
    width: 400px;
    height: 400px;
    pointer-events: none;
    opacity: 0.6;
}

.hero-decoration::before {
    content: '';
    position: absolute;
    inset: 0;
    background: 
        radial-gradient(circle at 30% 30%, var(--violet) 0%, transparent 50%),
        radial-gradient(circle at 70% 70%, var(--cyan) 0%, transparent 50%);
    border-radius: 50%;
    filter: blur(60px);
    animation: morphBlob 8s ease-in-out infinite;
}

@keyframes morphBlob {
    0%, 100% { transform: scale(1) rotate(0deg); }
    50% { transform: scale(1.1) rotate(180deg); }
}

/* ========================================
   风格信息条
   ======================================== */
.style-chips {
    display: flex;
    gap: var(--space-sm);
    flex-wrap: wrap;
    margin-bottom: var(--space-xl);
}

.chip {
    display: inline-flex;
    align-items: center;
    gap: 6px;
    padding: 6px 14px;
    font-size: var(--font-size-xs);
    font-weight: var(--font-weight-medium);
    color: var(--muted);
    background: var(--glass);
    border: 1px solid var(--border-color);
    border-radius: 100px;
    transition: all 0.3s ease;
}

.chip:hover {
    color: var(--ink);
    background: var(--glass-hi);
    border-color: rgba(255,255,255,0.4);
}

.chip-accent {
    background: linear-gradient(135deg, rgba(124, 77, 255, 0.2), rgba(0, 224, 255, 0.2));
    border-color: rgba(124, 77, 255, 0.4);
    color: var(--ink);
}

/* ========================================
   章节标题
   ======================================== */
.section-header {
    text-align: center;
    margin-bottom: var(--space-2xl);
}

.section-title {
    font-size: var(--font-size-2xl);
    font-weight: var(--font-weight-bold);
    line-height: var(--line-height-tight);
    margin-bottom: var(--space-sm);
}

.section-subtitle {
    font-size: var(--font-size-base);
    color: var(--muted);
    max-width: 34em;
    margin: 0 auto;
}

/* ========================================
   特性卡片网格
   ======================================== */
.features-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: var(--space-lg);
}

.feature-card {
    text-align: center;
    padding: var(--space-xl);
}

.feature-icon {
    width: 56px;
    height: 56px;
    margin: 0 auto var(--space-md);
    display: flex;
    align-items: center;
    justify-content: center;
    background: linear-gradient(135deg, rgba(124, 77, 255, 0.2), rgba(0, 224, 255, 0.2));
    border: 1px solid var(--border-color);
    border-radius: var(--radius);
}

.feature-icon svg {
    width: 28px;
    height: 28px;
    stroke: var(--cyan);
}

.feature-title {
    font-size: var(--font-size-lg);
    font-weight: var(--font-weight-bold);
    margin-bottom: var(--space-sm);
}

.feature-desc {
    font-size: var(--font-size-sm);
    color: var(--muted);
    line-height: var(--line-height-relaxed);
}

/* ========================================
   团队成员卡片
   ======================================== */
.team-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
    gap: var(--space-lg);
}

.team-card {
    text-align: center;
    padding: var(--space-xl);
}

.team-avatar {
    width: 100px;
    height: 100px;
    margin: 0 auto var(--space-md);
    border-radius: 50%;
    background: linear-gradient(135deg, var(--violet), var(--cyan));
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: var(--font-size-2xl);
    font-weight: var(--font-weight-bold);
    color: var(--ink);
    border: 2px solid var(--border-color);
}

.team-name {
    font-size: var(--font-size-lg);
    font-weight: var(--font-weight-bold);
    margin-bottom: var(--space-xs);
}

.team-role {
    font-size: var(--font-size-sm);
    color: var(--cyan);
    margin-bottom: var(--space-sm);
}

.team-bio {
    font-size: var(--font-size-sm);
    color: var(--muted);
    line-height: var(--line-height-relaxed);
}

/* ========================================
   表单系统
   ======================================== */
.form-group {
    margin-bottom: var(--space-md);
}

.form-label {
    display: block;
    font-size: var(--font-size-sm);
    font-weight: var(--font-weight-medium);
    color: var(--ink);
    margin-bottom: var(--space-sm);
}

.form-input,
.form-textarea {
    width: 100%;
    padding: 12px 16px;
    font-family: var(--font-family);
    font-size: var(--font-size-base);
    color: var(--ink);
    background: var(--glass);
    border: 1px solid var(--border-color);
    border-radius: var(--radius);
    transition: all 0.3s ease;
    min-height: 44px;
}

.form-textarea {
    min-height: 120px;
    resize: vertical;
}

.form-input:focus,
.form-textarea:focus {
    outline: none;
    border-color: var(--violet);
    background: var(--glass-hi);
    box-shadow: 0 0 0 3px rgba(124, 77, 255, 0.2);
}

.form-input::placeholder,
.form-textarea::placeholder {
    color: var(--muted);
}

/* ========================================
   页脚
   ======================================== */
.footer {
    background: rgba(7, 10, 28, 0.9);
    border-top: 1px solid var(--border-color);
    padding: var(--space-2xl) 0 var(--space-lg);
    margin-top: var(--space-3xl);
}

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

.footer-brand {
    display: flex;
    flex-direction: column;
    gap: var(--space-md);
}

.footer-brand-name {
    display: flex;
    align-items: center;
    gap: var(--space-sm);
    font-size: var(--font-size-lg);
    font-weight: var(--font-weight-bold);
    color: var(--ink);
}

.footer-brand-desc {
    font-size: var(--font-size-sm);
    color: var(--muted);
    line-height: var(--line-height-relaxed);
    max-width: 300px;
}

.footer-section-title {
    font-size: var(--font-size-sm);
    font-weight: var(--font-weight-bold);
    color: var(--ink);
    margin-bottom: var(--space-md);
    text-transform: uppercase;
    letter-spacing: 0.1em;
}

.footer-links {
    list-style: none;
    display: flex;
    flex-direction: column;
    gap: var(--space-sm);
}

.footer-links a {
    font-size: var(--font-size-sm);
    color: var(--muted);
    text-decoration: none;
    transition: color 0.3s ease;
}

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

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

/* ========================================
   徽章与开关
   ======================================== */
.badge {
    display: inline-flex;
    align-items: center;
    padding: 4px 10px;
    font-size: var(--font-size-xs);
    font-weight: var(--font-weight-medium);
    border-radius: 100px;
    text-transform: uppercase;
    letter-spacing: 0.05em;
}

.badge-primary {
    background: linear-gradient(135deg, var(--violet), var(--pink));
    color: var(--ink);
}

.badge-secondary {
    background: var(--glass);
    border: 1px solid var(--border-color);
    color: var(--muted);
}

.toggle {
    position: relative;
    width: 48px;
    height: 26px;
    background: var(--glass);
    border: 1px solid var(--border-color);
    border-radius: 100px;
    cursor: pointer;
    transition: all 0.3s ease;
}

.toggle::after {
    content: '';
    position: absolute;
    top: 2px;
    left: 2px;
    width: 20px;
    height: 20px;
    background: var(--muted);
    border-radius: 50%;
    transition: all 0.3s ease;
}

.toggle.active {
    background: linear-gradient(135deg, var(--violet), var(--cyan));
    border-color: var(--violet);
}

.toggle.active::after {
    left: calc(100% - 22px);
    background: var(--ink);
}

/* ========================================
   响应式适配
   ======================================== */
@media (max-width: 1024px) {
    .hero-decoration {
        width: 300px;
        height: 300px;
        opacity: 0.4;
    }
    
    .footer-content {
        grid-template-columns: 1fr 1fr;
    }
}

@media (max-width: 768px) {
    .navbar-menu {
        display: none;
        position: absolute;
        top: 72px;
        left: 0;
        right: 0;
        flex-direction: column;
        background: rgba(7, 10, 28, 0.95);
        backdrop-filter: blur(20px);
        padding: var(--space-lg);
        border-bottom: 1px solid var(--border-color);
    }
    
    .navbar-menu.active {
        display: flex;
    }
    
    .menu-toggle {
        display: block;
    }
    
    .navbar-cta .btn-secondary {
        display: none;
    }
    
    .hero {
        min-height: auto;
        padding: var(--space-2xl) 0;
    }
    
    .hero-decoration {
        display: none;
    }
    
    .hero-title {
        font-size: clamp(1.75rem, 8vw, 2.5rem);
    }
    
    .hero-actions {
        flex-direction: column;
    }
    
    .hero-actions .btn {
        width: 100%;
    }
    
    .features-grid,
    .team-grid {
        grid-template-columns: 1fr;
    }
    
    .footer-content {
        grid-template-columns: 1fr;
        gap: var(--space-lg);
    }
    
    .section {
        padding: var(--space-2xl) 0;
    }
}

@media (max-width: 375px) {
    .container {
        padding: 0 var(--space-md);
    }
    
    .glass-card {
        padding: var(--space-md);
    }
}

/* ========================================
   无障碍与动效偏好
   ======================================== */
@media (prefers-reduced-motion: reduce) {
    *, *::before, *::after {
        animation-duration: 0.01ms !important;
        animation-iteration-count: 1 !important;
        transition-duration: 0.01ms !important;
    }
    
    html {
        scroll-behavior: auto;
    }
}

/* 焦点可见样式 */
:focus-visible {
    outline: 2px solid var(--violet);
    outline-offset: 2px;
}

/* 跳过导航链接 */
.skip-link {
    position: absolute;
    top: -40px;
    left: 0;
    background: var(--violet);
    color: var(--ink);
    padding: 8px 16px;
    text-decoration: none;
    z-index: 9999;
}

.skip-link:focus {
    top: 0;
}