/* ========================================
   Teams下载 - 官网样式表 (仿 teamsqs.com)
   ======================================== */

/* ---------- CSS 变量 ---------- */
:root {
    --primary: #464EB8;
    --primary-hover: #3B42A2;
    --primary-light: #E8E9FF;
    --primary-dark: #333399;
    --text: #1a1a2e;
    --text-secondary: #5a5a7a;
    --text-muted: #8a8aa0;
    --bg: #ffffff;
    --bg-light: #f8f9fc;
    --bg-card: #ffffff;
    --border: #e8eaf0;
    --border-light: #f0f1f5;
    --success: #2D8C5A;
    --warning: #F47B20;
    --danger: #E74856;
    --shadow-sm: 0 1px 3px rgba(0,0,0,0.04);
    --shadow-md: 0 4px 16px rgba(0,0,0,0.06);
    --shadow-lg: 0 8px 30px rgba(0,0,0,0.08);
    --shadow-xl: 0 16px 48px rgba(0,0,0,0.10);
    --radius-sm: 8px;
    --radius-md: 12px;
    --radius-lg: 16px;
    --radius-xl: 24px;
    --font: 'Segoe UI', 'Microsoft YaHei', -apple-system, BlinkMacSystemFont, sans-serif;
    --transition: 0.25s cubic-bezier(0.4, 0, 0.2, 1);
    --max-width: 1200px;
}

/* ---------- 通用重置 ---------- */
*, *::before, *::after { margin: 0; padding: 0; box-sizing: border-box; }
html { scroll-behavior: smooth; scroll-padding-top: 80px; }
body {
    font-family: var(--font);
    font-size: 16px;
    line-height: 1.6;
    color: var(--text);
    background: var(--bg);
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}
a { text-decoration: none; color: inherit; }
img { max-width: 100%; display: block; }
ul, ol { list-style: none; }

.container {
    max-width: var(--max-width);
    margin: 0 auto;
    padding: 0 24px;
}

/* ---------- 头部导航 ---------- */
.header {
    position: sticky;
    top: 0;
    z-index: 1000;
    background: rgba(255,255,255,0.92);
    backdrop-filter: blur(20px);
    -webkit-backdrop-filter: blur(20px);
    border-bottom: 1px solid transparent;
    transition: border-color var(--transition), box-shadow var(--transition);
}
.header.scrolled {
    border-bottom-color: var(--border);
    box-shadow: var(--shadow-sm);
}
.header .container {
    display: flex;
    align-items: center;
    justify-content: space-between;
    height: 70px;
}

.logo {
    display: flex;
    align-items: center;
    gap: 10px;
    font-size: 20px;
    font-weight: 700;
    color: var(--text);
    transition: opacity var(--transition);
}
.logo:hover { opacity: 0.85; }
.logo-icon { display: flex; align-items: center; }

.nav { display: flex; align-items: center; gap: 8px; }
.nav-link {
    padding: 8px 16px;
    border-radius: 8px;
    font-size: 15px;
    font-weight: 500;
    color: var(--text-secondary);
    transition: color var(--transition), background var(--transition);
}
.nav-link:hover, .nav-link.active { color: var(--primary); background: var(--primary-light); }
.nav-download-btn {
    margin-left: 8px;
    padding: 8px 20px;
    background: var(--primary);
    color: #fff !important;
    border-radius: 8px;
    font-weight: 600;
    transition: background var(--transition), transform var(--transition), box-shadow var(--transition);
}
.nav-download-btn:hover {
    background: var(--primary-hover);
    transform: translateY(-1px);
    box-shadow: 0 4px 12px rgba(70,78,184,0.3);
}

.menu-toggle {
    display: none;
    flex-direction: column;
    gap: 5px;
    background: none;
    border: none;
    cursor: pointer;
    padding: 8px;
}
.menu-toggle span {
    display: block;
    width: 24px;
    height: 2px;
    background: var(--text);
    border-radius: 2px;
    transition: var(--transition);
}

/* ---------- Hero 区域 ---------- */
.hero {
    position: relative;
    background: linear-gradient(160deg, #464EB8 0%, #6C63FF 40%, #8B7CF6 100%);
    padding: 100px 0 160px;
    overflow: hidden;
}
.hero .container {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 60px;
    align-items: center;
}

.hero-content { position: relative; z-index: 2; }

.hero-title {
    font-size: clamp(36px, 5vw, 56px);
    font-weight: 800;
    color: #fff;
    line-height: 1.15;
    margin-bottom: 20px;
    letter-spacing: -0.5px;
}

.hero-subtitle {
    font-size: 18px;
    color: rgba(255,255,255,0.88);
    line-height: 1.7;
    margin-bottom: 36px;
    max-width: 460px;
}

.hero-buttons {
    display: flex;
    gap: 16px;
    flex-wrap: wrap;
}

.btn {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    padding: 14px 32px;
    border-radius: var(--radius-md);
    font-size: 16px;
    font-weight: 600;
    border: none;
    cursor: pointer;
    transition: transform var(--transition), box-shadow var(--transition), background var(--transition);
    white-space: nowrap;
}

.btn-primary {
    background: #fff;
    color: var(--primary);
    box-shadow: 0 4px 16px rgba(0,0,0,0.12);
}
.btn-primary:hover {
    transform: translateY(-2px);
    box-shadow: 0 8px 24px rgba(0,0,0,0.18);
    background: #fafaff;
}

.btn-outline {
    background: transparent;
    color: #fff;
    border: 2px solid rgba(255,255,255,0.4);
}
.btn-outline:hover {
    background: rgba(255,255,255,0.1);
    border-color: rgba(255,255,255,0.6);
    transform: translateY(-2px);
}

.btn-white {
    background: #fff;
    color: var(--primary);
}
.btn-white:hover {
    transform: translateY(-2px);
    box-shadow: 0 8px 24px rgba(0,0,0,0.15);
}

.hero-note {
    margin-top: 20px;
    font-size: 14px;
    color: rgba(255,255,255,0.6);
}

/* Hero 视觉插图 */
.hero-visual {
    position: relative;
    z-index: 2;
    display: flex;
    align-items: center;
    justify-content: center;
}

.hero-illustration {
    position: relative;
    width: 320px;
    height: 320px;
}

.illustration-card {
    position: absolute;
    background: rgba(255,255,255,0.15);
    backdrop-filter: blur(10px);
    border: 1px solid rgba(255,255,255,0.25);
    border-radius: var(--radius-lg);
    padding: 16px;
    transition: transform var(--transition);
}

.card-1 {
    top: 20px;
    left: 20px;
    width: 180px;
    animation: float1 6s ease-in-out infinite;
}
.card-2 {
    top: 100px;
    right: 20px;
    width: 200px;
    animation: float2 7s ease-in-out infinite;
}
.card-3 {
    bottom: 30px;
    left: 60px;
    width: 160px;
    animation: float3 5s ease-in-out infinite;
}

.card-avatar {
    width: 40px; height: 40px;
    background: rgba(255,255,255,0.3);
    border-radius: 10px;
    margin-bottom: 12px;
}
.card-avatar-group {
    display: flex;
    gap: 4px;
    margin-bottom: 12px;
}
.av {
    width: 32px; height: 32px;
    border-radius: 8px;
    background: rgba(255,255,255,0.25);
}
.av1 { background: rgba(255,255,255,0.4); }
.av2 { background: rgba(255,255,255,0.25); }
.av3 { background: rgba(255,255,255,0.35); }

.card-icon {
    font-size: 28px;
    margin-bottom: 12px;
}

.card-lines span {
    display: block;
    height: 6px;
    background: rgba(255,255,255,0.2);
    border-radius: 3px;
    margin-bottom: 8px;
}
.card-lines span:first-child { width: 70%; }
.card-lines span:last-child { width: 45%; }

@keyframes float1 { 0%,100%{transform:translateY(0)} 50%{transform:translateY(-12px)} }
@keyframes float2 { 0%,100%{transform:translateY(0)} 50%{transform:translateY(-16px)} }
@keyframes float3 { 0%,100%{transform:translateY(0)} 50%{transform:translateY(-10px)} }

/* Hero 波浪 */
.hero-wave {
    position: absolute;
    bottom: -2px;
    left: 0;
    right: 0;
    z-index: 3;
}
.hero-wave svg { width: 100%; height: 80px; display: block; }

/* ---------- 区块标题 ---------- */
.section-header {
    text-align: center;
    margin-bottom: 56px;
}
.section-header h2 {
    font-size: clamp(28px, 3.5vw, 38px);
    font-weight: 800;
    color: var(--text);
    margin-bottom: 12px;
    letter-spacing: -0.3px;
}
.section-header p {
    font-size: 17px;
    color: var(--text-secondary);
    max-width: 500px;
    margin: 0 auto;
}

/* ---------- 功能特色 ---------- */
.features {
    padding: 90px 0 80px;
    background: var(--bg-light);
}

.features-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
    gap: 24px;
}

.feature-card {
    background: var(--bg-card);
    border: 1px solid var(--border-light);
    border-radius: var(--radius-lg);
    padding: 32px 28px;
    transition: transform var(--transition), box-shadow var(--transition), border-color var(--transition);
    position: relative;
    overflow: hidden;
}
.feature-card::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    height: 3px;
    background: var(--primary);
    transform: scaleX(0);
    transition: transform var(--transition);
    border-radius: 0 0 var(--radius-sm) var(--radius-sm);
}
.feature-card:hover {
    transform: translateY(-6px);
    box-shadow: var(--shadow-lg);
    border-color: transparent;
}
.feature-card:hover::before { transform: scaleX(1); }

.feature-icon-wrapper { margin-bottom: 20px; display: inline-block; }

.feature-card h3 {
    font-size: 20px;
    font-weight: 700;
    color: var(--text);
    margin-bottom: 10px;
}

.feature-card p {
    font-size: 15px;
    color: var(--text-secondary);
    line-height: 1.7;
}

/* ---------- 统计区域 ---------- */
.stats-section {
    padding: 70px 0;
    background: var(--bg);
}

.stats-grid {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 24px;
}

.stat-card {
    text-align: center;
    padding: 32px 16px;
    background: var(--bg-light);
    border-radius: var(--radius-lg);
    transition: transform var(--transition), box-shadow var(--transition);
}
.stat-card:hover {
    transform: translateY(-4px);
    box-shadow: var(--shadow-md);
}

.stat-number {
    font-size: 44px;
    font-weight: 800;
    color: var(--primary);
    line-height: 1;
    display: inline;
}
.stat-unit {
    font-size: 20px;
    font-weight: 700;
    color: var(--primary);
    display: inline;
    margin-left: 2px;
}
.stat-label {
    margin-top: 8px;
    font-size: 15px;
    color: var(--text-secondary);
    font-weight: 500;
}

/* ---------- 移动端下载 ---------- */
.mobile-section {
    padding: 90px 0;
    background: linear-gradient(180deg, var(--bg-light) 0%, var(--bg) 100%);
}

.mobile-content {
    display: grid;
    grid-template-columns: 1fr auto;
    gap: 60px;
    align-items: center;
}

.mobile-text h2 {
    font-size: clamp(26px, 3vw, 34px);
    font-weight: 800;
    color: var(--text);
    margin-bottom: 16px;
}
.mobile-text p {
    font-size: 16px;
    color: var(--text-secondary);
    line-height: 1.7;
    margin-bottom: 28px;
    max-width: 480px;
}

.store-badges {
    display: flex;
    gap: 14px;
    flex-wrap: wrap;
}

.store-badge {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    padding: 12px 24px;
    border-radius: var(--radius-sm);
    font-size: 15px;
    font-weight: 600;
    transition: transform var(--transition), box-shadow var(--transition), opacity var(--transition);
}
.store-badge:hover {
    transform: translateY(-2px);
    box-shadow: var(--shadow-md);
}
.app-store {
    background: #000;
    color: #fff;
}
.google-play {
    background: var(--bg);
    color: var(--text);
    border: 1px solid var(--border);
}

.mobile-qr { text-align: center; }

.qr-wrapper {
    display: inline-block;
    padding: 20px;
    background: var(--bg);
    border: 1px solid var(--border);
    border-radius: var(--radius-lg);
    box-shadow: var(--shadow-md);
}
.qr-code { line-height: 0; }
.qr-hint {
    margin-top: 14px;
    font-size: 14px;
    color: var(--text-muted);
}

/* ---------- 新闻资讯 ---------- */
.news-section {
    padding: 90px 0;
    background: var(--bg);
}

.news-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(340px, 1fr));
    gap: 20px;
    margin-bottom: 40px;
}

.news-card {
    display: flex;
    gap: 16px;
    padding: 20px;
    background: var(--bg-light);
    border-radius: var(--radius-md);
    border: 1px solid transparent;
    transition: transform var(--transition), box-shadow var(--transition), border-color var(--transition);
}
.news-card:hover {
    transform: translateY(-3px);
    box-shadow: var(--shadow-md);
    border-color: var(--border);
    background: var(--bg);
}

.news-thumb {
    flex-shrink: 0;
    width: 48px;
    height: 48px;
    border-radius: var(--radius-sm);
    overflow: hidden;
}

.news-body { flex: 1; min-width: 0; }

.news-body h4 {
    font-size: 16px;
    font-weight: 600;
    color: var(--text);
    margin-bottom: 6px;
    overflow: hidden;
    text-overflow: ellipsis;
    white-space: nowrap;
    transition: color var(--transition);
}
.news-card:hover .news-body h4 { color: var(--primary); }

.news-body p {
    font-size: 14px;
    color: var(--text-secondary);
    margin-bottom: 8px;
    display: -webkit-box;
    -webkit-line-clamp: 2;
    -webkit-box-orient: vertical;
    overflow: hidden;
}

.news-date {
    font-size: 12px;
    color: var(--text-muted);
}

.news-more { text-align: center; }

/* ---------- CTA 区域 ---------- */
.cta-section { padding: 0 0 90px; }

.cta-card {
    text-align: center;
    padding: 64px 40px;
    background: linear-gradient(135deg, #464EB8, #6C63FF);
    border-radius: var(--radius-xl);
    box-shadow: var(--shadow-xl);
}
.cta-card h2 {
    font-size: clamp(24px, 3vw, 34px);
    font-weight: 800;
    color: #fff;
    margin-bottom: 12px;
}
.cta-card p {
    font-size: 17px;
    color: rgba(255,255,255,0.85);
    margin-bottom: 32px;
    max-width: 500px;
    margin-left: auto;
    margin-right: auto;
}

/* ---------- 页脚 ---------- */
.footer {
    background: #1a1a2e;
    color: #b0b0c8;
    padding: 64px 0 28px;
}

.footer-grid {
    display: grid;
    grid-template-columns: 1.5fr 1fr 1fr 1fr;
    gap: 40px;
    margin-bottom: 50px;
}

.footer-brand p {
    font-size: 14px;
    line-height: 1.7;
    max-width: 280px;
}

.footer-logo {
    display: flex;
    align-items: center;
    gap: 10px;
    margin-bottom: 16px;
    font-size: 18px;
    font-weight: 700;
    color: #fff;
}

.footer-links h4 {
    font-size: 14px;
    font-weight: 700;
    color: #fff;
    text-transform: uppercase;
    letter-spacing: 0.5px;
    margin-bottom: 18px;
}

.footer-links a {
    display: block;
    font-size: 14px;
    color: #b0b0c8;
    padding: 6px 0;
    transition: color var(--transition);
}
.footer-links a:hover { color: #fff; }

.footer-bottom {
    padding-top: 24px;
    border-top: 1px solid rgba(255,255,255,0.08);
    text-align: center;
    font-size: 13px;
    color: #6a6a80;
}

/* ========================================
   下载页样式
   ======================================== */
.download-page-body {
    background: var(--bg-light);
    min-height: 100vh;
}

.download-hero {
    padding: 80px 0 70px;
    text-align: center;
}

.download-hero .icon {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    width: 90px;
    height: 90px;
    background: var(--primary-light);
    border-radius: var(--radius-xl);
    margin-bottom: 24px;
}
.download-hero .icon svg { width: 48px; height: 48px; }

.download-hero h1 {
    font-size: clamp(28px, 4vw, 40px);
    font-weight: 800;
    color: var(--text);
    margin-bottom: 10px;
}

.download-hero .subtitle {
    font-size: 17px;
    color: var(--text-secondary);
    margin-bottom: 16px;
}

.download-hero .version {
    display: inline-block;
    padding: 6px 14px;
    background: var(--primary-light);
    color: var(--primary);
    font-size: 14px;
    font-weight: 600;
    border-radius: 20px;
}

.download-options {
    padding-bottom: 90px;
}

.download-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
    gap: 20px;
    max-width: 900px;
    margin: 0 auto;
}

.download-card {
    background: var(--bg);
    border: 1px solid var(--border);
    border-radius: var(--radius-lg);
    padding: 32px 24px;
    text-align: center;
    transition: transform var(--transition), box-shadow var(--transition), border-color var(--transition);
}
.download-card:hover {
    transform: translateY(-4px);
    box-shadow: var(--shadow-lg);
    border-color: var(--primary);
}

.dl-icon {
    margin-bottom: 18px;
    display: inline-flex;
}
.dl-icon svg { width: 44px; height: 44px; }

.download-card h3 {
    font-size: 18px;
    font-weight: 700;
    color: var(--text);
    margin-bottom: 6px;
}
.download-card .dl-size {
    font-size: 13px;
    color: var(--text-muted);
    margin-bottom: 20px;
}

.download-card .btn-primary {
    width: 100%;
    justify-content: center;
    font-size: 15px;
    padding: 12px 24px;
}

.download-info {
    margin-top: 50px;
    max-width: 600px;
    margin-left: auto;
    margin-right: auto;
    text-align: center;
}

.download-info .info-box {
    background: var(--bg);
    border: 1px solid var(--border);
    border-radius: var(--radius-md);
    padding: 24px;
    margin-bottom: 24px;
}
.download-info .info-box p {
    font-size: 15px;
    color: var(--text-secondary);
    margin: 8px 0;
    line-height: 1.6;
}
.download-info .info-box strong {
    color: var(--text);
    display: inline-block;
    min-width: 100px;
}

.download-info .back-link {
    font-size: 15px;
    color: var(--text-secondary);
    transition: color var(--transition);
}
.download-info .back-link:hover { color: var(--primary); }

/* ---------- 响应式 ---------- */
@media (max-width: 992px) {
    .hero .container {
        grid-template-columns: 1fr;
        text-align: center;
    }
    .hero-subtitle { max-width: 100%; margin-left: auto; margin-right: auto; }
    .hero-buttons { justify-content: center; }
    .hero-visual { display: none; }
    .hero { padding: 80px 0 130px; }

    .features-grid { grid-template-columns: repeat(2, 1fr); }
    .stats-grid { grid-template-columns: repeat(2, 1fr); }
    .mobile-content { grid-template-columns: 1fr; text-align: center; }
    .mobile-text p { max-width: 100%; }
    .store-badges { justify-content: center; }
    .news-grid { grid-template-columns: 1fr; }
    .footer-grid { grid-template-columns: 1fr 1fr; }
}

@media (max-width: 768px) {
    .nav {
        position: fixed;
        top: 70px;
        left: 0;
        right: 0;
        bottom: 0;
        background: rgba(255,255,255,0.98);
        backdrop-filter: blur(20px);
        flex-direction: column;
        align-items: stretch;
        padding: 24px;
        gap: 4px;
        transform: translateX(100%);
        transition: transform var(--transition);
        z-index: 999;
    }
    .nav.open { transform: translateX(0); }
    .nav-link { padding: 14px 16px; font-size: 17px; border-radius: var(--radius-sm); }
    .nav-download-btn { margin-left: 0; text-align: center; margin-top: 8px; }
    .menu-toggle { display: flex; }

    .hero { padding: 60px 0 110px; }
    .hero-title { font-size: 32px; }
    .hero-subtitle { font-size: 16px; }
    .hero-wave svg { height: 50px; }

    .features { padding: 60px 0; }
    .features-grid { grid-template-columns: 1fr; }
    .section-header { margin-bottom: 40px; }
    .section-header h2 { font-size: 26px; }

    .stats-grid { grid-template-columns: repeat(2, 1fr); gap: 12px; }
    .stat-number { font-size: 34px; }
    .stat-card { padding: 24px 12px; }

    .mobile-section { padding: 60px 0; }

    .news-section { padding: 60px 0; }

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

    .footer-grid { grid-template-columns: 1fr; gap: 32px; }
    .footer-brand p { max-width: 100%; }

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

@media (max-width: 480px) {
    .container { padding: 0 16px; }
    .hero { padding: 50px 0 100px; }
    .hero-title { font-size: 28px; }
    .hero-buttons { flex-direction: column; }
    .hero-buttons .btn { justify-content: center; }
    .stats-grid { grid-template-columns: 1fr 1fr; }
    .news-grid { grid-template-columns: 1fr; }
}

/* PC端适配 (1900px+) */
@media (min-width: 1900px) {
    .container { max-width: 1400px; }
}