/* ===================================================
   ToDesk — 蓝白 · 清新科技风格
   =================================================== */

@import url('https://fonts.googleapis.com/css2?family=Inter:wght@400;500;600;700;800;900&display=swap');

:root {
    --primary: #2563EB;
    --primary-light: #60A5FA;
    --primary-dark: #1D4ED8;
    --accent: #06B6D4;
    --accent-light: #67E8F9;
    --bg: #F8FAFC;
    --bg-elevated: #FFFFFF;
    --bg-card: #FFFFFF;
    --bg-card-hover: #F1F5F9;
    --surface: #FFFFFF;
    --text-primary: #0F172A;
    --text-secondary: #475569;
    --text-muted: #94A3B8;
    --border: rgba(0,0,0,0.06);
    --border-hover: rgba(37,99,235,0.3);
    --glow-primary: rgba(37,99,235,0.2);
    --glow-accent: rgba(6,182,212,0.18);
    --radius-sm: 10px;
    --radius: 16px;
    --radius-lg: 24px;
    --radius-xl: 32px;
    --shadow-sm: 0 1px 3px rgba(0,0,0,0.04);
    --shadow: 0 4px 20px rgba(0,0,0,0.06);
    --shadow-lg: 0 12px 40px rgba(0,0,0,0.08);
    --transition: 0.35s cubic-bezier(0.22, 0.61, 0.36, 1);
}

*, *::before, *::after { margin: 0; padding: 0; box-sizing: border-box; }
html { scroll-behavior: smooth; }

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

/* ============================================
   背景装饰
   ============================================ */
.bg-layer {
    position: fixed;
    inset: 0;
    pointer-events: none;
    z-index: 0;
}
.bg-layer .glow-orb {
    position: absolute;
    border-radius: 50%;
    filter: blur(140px);
    opacity: 0.5;
    animation: orbDrift 22s ease-in-out infinite;
}
.bg-layer .glow-orb:nth-child(1) {
    width: 700px; height: 700px;
    background: rgba(37,99,235,0.08);
    top: -250px; right: -120px;
    animation-delay: 0s;
}
.bg-layer .glow-orb:nth-child(2) {
    width: 550px; height: 550px;
    background: rgba(6,182,212,0.06);
    bottom: -200px; left: -120px;
    animation-delay: -8s;
}
.bg-layer .glow-orb:nth-child(3) {
    width: 450px; height: 450px;
    background: rgba(37,99,235,0.04);
    top: 45%; left: 55%;
    transform: translate(-50%, -50%);
    animation-delay: -15s;
}
@keyframes orbDrift {
    0%, 100% { transform: translate(0, 0) scale(1); }
    25% { transform: translate(50px, -40px) scale(1.06); }
    50% { transform: translate(-30px, 30px) scale(0.94); }
    75% { transform: translate(-40px, -15px) scale(1.03); }
}

.bg-dots {
    position: fixed;
    inset: 0;
    pointer-events: none;
    z-index: 0;
    opacity: 0.3;
    background-image: radial-gradient(circle, rgba(37,99,235,0.15) 1px, transparent 1px);
    background-size: 44px 44px;
}

/* ============================================
   导航栏
   ============================================ */
.nav {
    position: fixed;
    top: 0; left: 0; right: 0;
    z-index: 100;
    height: 68px;
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 0 40px;
    background: rgba(255,255,255,0.8);
    backdrop-filter: blur(20px) saturate(150%);
    -webkit-backdrop-filter: blur(20px) saturate(150%);
    border-bottom: 1px solid var(--border);
    transition: all 0.4s;
}
.nav.scrolled {
    background: rgba(255,255,255,0.95);
    box-shadow: 0 1px 20px rgba(0,0,0,0.05);
}
.nav-brand {
    display: flex;
    align-items: center;
    gap: 10px;
    text-decoration: none;
}
.nav-logo-icon {
    width: 34px; height: 34px;
    background: linear-gradient(135deg, var(--primary), var(--accent));
    border-radius: 10px;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 16px;
    color: #fff;
    font-weight: 900;
}
.nav-logo-text {
    font-size: 20px;
    font-weight: 800;
    color: var(--text-primary);
    letter-spacing: -0.5px;
}
.nav-links {
    display: flex;
    gap: 4px;
    background: rgba(37,99,235,0.04);
    border-radius: 14px;
    padding: 4px;
}
.nav-links a {
    color: var(--text-secondary);
    text-decoration: none;
    font-size: 14px;
    font-weight: 500;
    padding: 8px 20px;
    border-radius: 11px;
    transition: var(--transition);
}
.nav-links a:hover { color: var(--primary); }
.nav-links a.active {
    color: #fff;
    background: var(--primary);
    box-shadow: 0 4px 15px var(--glow-primary);
}

/* ============================================
   主布局
   ============================================ */
main {
    position: relative;
    z-index: 1;
    max-width: 1200px;
    margin: 0 auto;
    padding: 100px 32px 80px;
}

/* ============================================
   英雄区域 · 首页
   ============================================ */
.hero {
    text-align: center;
    padding: 20px 0 70px;
}

/* 视觉装饰 */
.hero-visual {
    position: relative;
    width: 340px;
    height: 220px;
    margin: 0 auto 50px;
}
.hero-visual .glass-panel {
    position: absolute;
    border-radius: 20px;
    border: 1px solid rgba(37,99,235,0.12);
    background: rgba(255,255,255,0.7);
    box-shadow: var(--shadow);
    backdrop-filter: blur(8px);
}
.hero-visual .panel-pc {
    width: 200px; height: 130px;
    top: 0; left: 0;
    box-shadow: 0 20px 60px rgba(37,99,235,0.06);
    display: flex;
    align-items: center;
    justify-content: center;
    overflow: hidden;
}
.hero-visual .panel-pc .pc-inner {
    width: 82%; height: 70%;
    background: #F1F5F9;
    border-radius: 6px;
    position: relative;
}
.hero-visual .panel-pc .pc-inner .dot {
    position: absolute;
    width: 10px; height: 10px;
    background: var(--primary);
    border-radius: 50%;
    box-shadow: 0 0 20px var(--glow-primary);
    animation: floatAround 4s ease-in-out infinite;
}
@keyframes floatAround {
    0%, 100% { top: 30%; left: 30%; }
    25% { top: 25%; left: 65%; }
    50% { top: 60%; left: 60%; }
    75% { top: 55%; left: 25%; }
}
.hero-visual .panel-phone {
    width: 55px; height: 95px;
    top: 15px; right: 30px;
    border-radius: 14px;
    box-shadow: 0 15px 40px rgba(37,99,235,0.04);
    display: flex;
    justify-content: center;
    padding-top: 8px;
}
.hero-visual .panel-phone::before {
    content: ''; width: 18px; height: 3px;
    background: rgba(37,99,235,0.15);
    border-radius: 2px;
}
.hero-visual .connector {
    position: absolute;
    top: 60px; left: 200px;
    width: 50px; height: 2px;
    background: linear-gradient(90deg, rgba(37,99,235,0.4), transparent);
}
.hero-visual .connector .data-pulse {
    position: absolute;
    width: 8px; height: 100%;
    background: var(--accent);
    border-radius: 2px;
    box-shadow: 0 0 12px var(--glow-accent);
    animation: pulse 1.8s ease-in-out infinite;
}
@keyframes pulse {
    0%, 100% { left: 0; opacity: 0; }
    50% { opacity: 1; }
    100% { left: 42px; opacity: 0; }
}

/* 标签 */
.hero-badge {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    padding: 6px 18px 6px 6px;
    background: rgba(37,99,235,0.06);
    border: 1px solid rgba(37,99,235,0.15);
    border-radius: 50px;
    font-size: 13px;
    color: var(--primary);
    margin-bottom: 28px;
}
.hero-badge .badge-dot {
    width: 8px; height: 8px;
    background: var(--primary);
    border-radius: 50%;
    animation: blink 2s ease-in-out infinite;
}
@keyframes blink {
    0%, 100% { opacity: 1; }
    50% { opacity: 0.3; }
}

/* 标题 */
.hero-title {
    font-size: clamp(40px, 7vw, 72px);
    font-weight: 900;
    letter-spacing: -2px;
    line-height: 1.1;
    margin-bottom: 24px;
}
.hero-title .gradient-text {
    background: linear-gradient(135deg, var(--primary-dark) 0%, var(--primary) 40%, var(--accent) 100%);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}
.hero-desc {
    font-size: 18px;
    color: var(--text-secondary);
    line-height: 1.8;
    max-width: 480px;
    margin: 0 auto 42px;
}

/* 按钮组 */
.hero-actions {
    display: flex;
    gap: 16px;
    justify-content: center;
    flex-wrap: wrap;
}
.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 10px;
    padding: 16px 36px;
    border-radius: 16px;
    font-size: 16px;
    font-weight: 600;
    text-decoration: none;
    cursor: pointer;
    transition: all 0.4s cubic-bezier(0.22, 0.61, 0.36, 1);
    border: none;
    font-family: inherit;
    white-space: nowrap;
}
.btn-primary {
    background: var(--primary);
    color: #fff;
    box-shadow: 0 6px 24px var(--glow-primary);
    position: relative;
    overflow: hidden;
}
.btn-primary::after {
    content: '';
    position: absolute;
    inset: 0;
    background: linear-gradient(135deg, transparent 40%, rgba(255,255,255,0.2), transparent 60%);
    transform: translateX(-100%);
    transition: transform 0.5s;
}
.btn-primary:hover::after { transform: translateX(100%); }
.btn-primary:hover {
    transform: translateY(-2px);
    box-shadow: 0 10px 35px var(--glow-primary), 0 0 50px rgba(37,99,235,0.1);
}
.btn-outline {
    background: var(--bg-elevated);
    border: 1.5px solid rgba(37,99,235,0.2);
    color: var(--primary);
}
.btn-outline:hover {
    border-color: var(--primary);
    background: rgba(37,99,235,0.04);
}
.btn-arrow { transition: transform 0.3s; }
.btn-primary:hover .btn-arrow,
.btn-outline:hover .btn-arrow {
    transform: translateX(3px);
}

/* ============================================
   统计区
   ============================================ */
.stats-row {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 20px;
    margin-top: 60px;
}
.stat-card {
    text-align: center;
    padding: 36px 20px;
    background: var(--bg-card);
    border: 1px solid var(--border);
    border-radius: var(--radius-lg);
    box-shadow: var(--shadow-sm);
    transition: var(--transition);
    position: relative;
    overflow: hidden;
}
.stat-card::before {
    content: '';
    position: absolute;
    top: 0; left: 0; right: 0;
    height: 3px;
    background: linear-gradient(90deg, transparent, var(--primary), transparent);
    opacity: 0;
    transition: opacity 0.3s;
}
.stat-card:hover::before { opacity: 1; }
.stat-card:hover {
    transform: translateY(-4px);
    box-shadow: var(--shadow);
    border-color: var(--border-hover);
}
.stat-value {
    display: block;
    font-size: 42px;
    font-weight: 900;
    letter-spacing: -1px;
    background: linear-gradient(135deg, var(--primary), var(--accent));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
    margin-bottom: 6px;
}
.stat-desc {
    font-size: 14px;
    color: var(--text-muted);
    font-weight: 500;
}

/* ============================================
   功能区
   ============================================ */
.section-label {
    text-align: center;
    margin: 70px 0 10px;
    font-size: 12px;
    font-weight: 700;
    text-transform: uppercase;
    letter-spacing: 3px;
    color: var(--primary);
}
.section-title {
    text-align: center;
    font-size: 32px;
    font-weight: 800;
    margin-bottom: 44px;
    letter-spacing: -0.5px;
    color: var(--text-primary);
}

.features-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
    gap: 18px;
}
.feature-card {
    background: var(--bg-card);
    border: 1px solid var(--border);
    border-radius: var(--radius-lg);
    box-shadow: var(--shadow-sm);
    padding: 32px 28px;
    transition: all 0.4s cubic-bezier(0.22, 0.61, 0.36, 1);
    position: relative;
    overflow: hidden;
    cursor: default;
}
.feature-card:hover {
    transform: translateY(-6px);
    border-color: var(--border-hover);
    box-shadow: var(--shadow-lg), 0 0 40px rgba(37,99,235,0.04);
}
.feature-icon {
    width: 50px; height: 50px;
    border-radius: 14px;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 24px;
    margin-bottom: 20px;
    background: linear-gradient(135deg, rgba(37,99,235,0.08), rgba(6,182,212,0.06));
    border: 1px solid rgba(37,99,235,0.1);
    transition: var(--transition);
}
.feature-card:hover .feature-icon {
    background: linear-gradient(135deg, var(--primary), var(--accent));
    border-color: transparent;
}
.feature-card h3 {
    font-size: 18px;
    font-weight: 700;
    margin-bottom: 10px;
    letter-spacing: -0.3px;
    color: var(--text-primary);
}
.feature-card p {
    font-size: 14px;
    color: var(--text-secondary);
    line-height: 1.7;
}

/* 功能卡序号 */
.feature-card .f-num {
    position: absolute;
    top: 20px; right: 24px;
    font-size: 60px;
    font-weight: 900;
    color: rgba(37,99,235,0.03);
    line-height: 1;
    pointer-events: none;
    transition: color 0.3s;
}
.feature-card:hover .f-num { color: rgba(37,99,235,0.07); }

/* ============================================
   页脚
   ============================================ */
.footer {
    text-align: center;
    padding: 50px 20px 40px;
    position: relative;
    z-index: 1;
    border-top: 1px solid var(--border);
    margin-top: 80px;
}
.footer-brand {
    font-size: 16px;
    font-weight: 700;
    color: var(--text-primary);
    margin-bottom: 6px;
}
.footer-text {
    font-size: 13px;
    color: var(--text-muted);
}

/* ============================================
   下载页
   ============================================ */
.dl-page {
    min-height: calc(100vh - 68px);
    display: flex;
    align-items: center;
    justify-content: center;
    padding: 80px 32px 60px;
}
.dl-card {
    display: flex;
    align-items: center;
    gap: 72px;
    max-width: 920px;
    animation: slideIn 0.7s cubic-bezier(0.22, 0.61, 0.36, 1);
}
@keyframes slideIn {
    from { opacity: 0; transform: translateY(30px); }
    to { opacity: 1; transform: translateY(0); }
}
.dl-icon-wrap {
    flex-shrink: 0;
    position: relative;
}
.dl-app-icon {
    width: 160px; height: 160px;
    background: linear-gradient(135deg, var(--primary), var(--accent));
    border-radius: 36px;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 64px;
    box-shadow: 0 20px 50px var(--glow-primary), 0 0 40px var(--glow-accent);
    animation: iconFloat 4s ease-in-out infinite;
    position: relative;
    z-index: 1;
}
@keyframes iconFloat {
    0%, 100% { transform: translateY(0); }
    50% { transform: translateY(-8px); }
}
.dl-app-icon::after {
    content: '';
    position: absolute;
    inset: -10px;
    border-radius: 44px;
    border: 2px solid rgba(37,99,235,0.15);
    animation: iconRing 4s ease-in-out infinite;
}
@keyframes iconRing {
    0%, 100% { transform: scale(1); opacity: 0.4; }
    50% { transform: scale(1.08); opacity: 0.1; }
}

.dl-info { flex: 1; }
.dl-tag {
    display: inline-block;
    padding: 5px 15px;
    background: rgba(37,99,235,0.06);
    border: 1px solid rgba(37,99,235,0.2);
    border-radius: 20px;
    font-size: 12px;
    color: var(--primary);
    margin-bottom: 16px;
    font-weight: 600;
}
.dl-info h1 {
    font-size: 50px;
    font-weight: 900;
    letter-spacing: -1.5px;
    margin-bottom: 8px;
    background: linear-gradient(135deg, var(--text-primary), var(--primary));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}
.dl-platform {
    font-size: 16px;
    color: var(--accent);
    margin-bottom: 22px;
    font-weight: 500;
}
.dl-meta-row {
    display: flex;
    gap: 24px;
    margin-bottom: 22px;
    font-size: 13px;
    color: var(--text-secondary);
    flex-wrap: wrap;
}
.dl-list {
    list-style: none;
    margin-bottom: 30px;
}
.dl-list li {
    display: flex;
    align-items: center;
    gap: 10px;
    padding: 8px 0;
    font-size: 14px;
    color: var(--text-secondary);
    transition: color 0.2s;
}
.dl-list li:hover { color: var(--text-primary); }
.dl-list li::before {
    content: '';
    width: 6px; height: 6px;
    background: var(--accent);
    border-radius: 50%;
    flex-shrink: 0;
    box-shadow: 0 0 8px var(--glow-accent);
}
.dl-btn-group {
    display: flex;
    gap: 14px;
    flex-wrap: wrap;
}
.dl-note {
    font-size: 12px;
    color: var(--text-muted);
    margin-top: 16px;
}

/* ============================================
   404页
   ============================================ */
.error-page-wrap {
    min-height: calc(100vh - 68px);
    display: flex;
    align-items: center;
    justify-content: center;
    padding: 80px 32px 60px;
    text-align: center;
}
.error-block {
    animation: slideIn 0.7s cubic-bezier(0.22, 0.61, 0.36, 1);
}
.error-icon-large {
    width: 140px; height: 140px;
    background: linear-gradient(135deg, var(--primary), var(--accent));
    border-radius: 38px;
    margin: 0 auto 40px;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 60px;
    box-shadow: 0 20px 60px var(--glow-primary), 0 0 50px var(--glow-accent);
    animation: iconFloat 5s ease-in-out infinite;
}
.error-num {
    font-size: 140px;
    font-weight: 900;
    line-height: 1;
    letter-spacing: -6px;
    background: linear-gradient(135deg, var(--primary), var(--accent));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
    margin-bottom: 16px;
}
.error-block h1 {
    font-size: 28px;
    font-weight: 700;
    margin-bottom: 10px;
}
.error-block p {
    font-size: 16px;
    color: var(--text-secondary);
    margin-bottom: 36px;
}
.error-actions {
    display: flex;
    gap: 14px;
    justify-content: center;
    flex-wrap: wrap;
}

/* ============================================
   滚动动画类
   ============================================ */
.anim-up {
    opacity: 0;
    transform: translateY(36px);
    transition: all 0.7s cubic-bezier(0.22, 0.61, 0.36, 1);
}
.anim-up.visible {
    opacity: 1;
    transform: translateY(0);
}

/* ============================================
   响应式
   ============================================ */
@media (max-width: 900px) {
    main { padding: 90px 20px 60px; }
    .hero-title { font-size: 38px; letter-spacing: -1px; }
    .hero-desc { font-size: 16px; }
    .stats-row { grid-template-columns: repeat(3, 1fr); gap: 12px; }
    .stat-card { padding: 24px 12px; }
    .stat-value { font-size: 30px; }
    .dl-card { flex-direction: column; text-align: center; gap: 36px; }
    .dl-info h1 { font-size: 38px; }
    .dl-meta-row { justify-content: center; }
    .dl-list li { justify-content: center; }
    .dl-btn-group { justify-content: center; }
    .features-grid { grid-template-columns: 1fr 1fr; }
}

@media (max-width: 640px) {
    .nav { padding: 0 16px; }
    .nav-logo-text { display: none; }
    .hero-title { font-size: 32px; }
    .stats-row { grid-template-columns: 1fr; gap: 10px; }
    .features-grid { grid-template-columns: 1fr; }
    .hero-actions { flex-direction: column; align-items: center; }
    .btn { width: 100%; max-width: 300px; }
    .error-num { font-size: 90px; }
    .section-title { font-size: 24px; }
    .feature-card .f-num { display: none; }
}