/* ===== 基础重置与变量 ===== */
:root {
    --primary: #00BCD4;
    --primary-dark: #0097A7;
    --primary-light: #26C6DA;
    --accent: #4DD0E1;
    --gradient: linear-gradient(135deg, #00BCD4, #26C6DA);
    --gradient-alt: linear-gradient(135deg, #00BCD4 0%, #4DD0E1 50%, #80DEEA 100%);
    --bg: #ffffff;
    --bg-soft: #f8fafa;
    --bg-card: #ffffff;
    --text: #1a2332;
    --text-secondary: #5a6a7e;
    --text-light: #8896a6;
    --border: #e8edf2;
    --shadow-sm: 0 2px 8px rgba(0,0,0,0.04);
    --shadow-md: 0 8px 30px rgba(0,0,0,0.06);
    --shadow-lg: 0 20px 60px rgba(0,0,0,0.08);
    --shadow-glow: 0 8px 40px rgba(0,188,212,0.15);
    --radius: 16px;
    --radius-lg: 24px;
    --radius-xl: 32px;
}

* { margin: 0; padding: 0; box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
    font-family: 'Noto Sans SC', -apple-system, BlinkMacSystemFont, sans-serif;
    background: var(--bg);
    color: var(--text);
    line-height: 1.6;
    overflow-x: hidden;
    -webkit-font-smoothing: antialiased;
}
img { max-width: 100%; display: block; }

/* ===== 导航栏 ===== */
.navbar {
    position: fixed; top: 0; left: 0; right: 0; z-index: 1000;
    padding: 16px 0;
    transition: all 0.4s cubic-bezier(0.4,0,0.2,1);
}
.navbar.scrolled {
    background: rgba(255,255,255,0.92);
    backdrop-filter: blur(20px);
    -webkit-backdrop-filter: blur(20px);
    box-shadow: 0 1px 20px rgba(0,0,0,0.06);
    padding: 10px 0;
}
.nav-container {
    max-width: 1200px; margin: 0 auto; padding: 0 24px;
    display: flex; align-items: center; justify-content: space-between;
}
.nav-brand { display: flex; align-items: center; gap: 10px; }
.nav-logo { width: 36px; height: 36px; border-radius: 10px; }
.nav-title { font-weight: 700; font-size: 18px; color: var(--text); }
.nav-cta {
    padding: 10px 24px; border-radius: 50px;
    background: var(--gradient); color: #fff;
    text-decoration: none; font-weight: 600; font-size: 14px;
    transition: all 0.3s ease;
    box-shadow: 0 4px 15px rgba(0,188,212,0.3);
}
.nav-cta:hover { transform: translateY(-2px); box-shadow: 0 6px 25px rgba(0,188,212,0.4); }

/* ===== Hero 区域 ===== */
.hero {
    min-height: 100vh; display: flex; align-items: center; justify-content: center;
    padding: 120px 24px 80px; position: relative; overflow: hidden;
    background: linear-gradient(180deg, #ffffff 0%, #f0fafb 50%, #ffffff 100%);
    flex-wrap: wrap; gap: 40px;
}
.hero-bg-shapes { position: absolute; inset: 0; pointer-events: none; }
.shape {
    position: absolute; border-radius: 50%; opacity: 0.08;
    background: var(--gradient);
}
.shape-1 { width: 600px; height: 600px; top: -200px; right: -200px; animation: float 8s ease-in-out infinite; }
.shape-2 { width: 400px; height: 400px; bottom: -100px; left: -150px; animation: float 10s ease-in-out infinite reverse; }
.shape-3 { width: 200px; height: 200px; top: 40%; left: 20%; animation: float 6s ease-in-out infinite 2s; }

@keyframes float {
    0%, 100% { transform: translate(0, 0) scale(1); }
    50% { transform: translate(20px, -30px) scale(1.05); }
}

.hero-content { max-width: 560px; z-index: 2; opacity: 0; transform: translateY(30px); transition: all 0.8s cubic-bezier(0.4,0,0.2,1); }
.hero.visible .hero-content { opacity: 1; transform: translateY(0); }

.hero-badge {
    display: inline-flex; align-items: center; gap: 8px;
    padding: 8px 20px; border-radius: 50px;
    background: rgba(0,188,212,0.08); border: 1px solid rgba(0,188,212,0.15);
    font-size: 13px; font-weight: 500; color: var(--primary-dark);
    margin-bottom: 24px;
}
.badge-dot {
    width: 6px; height: 6px; border-radius: 50%;
    background: var(--primary); animation: pulse 2s ease-in-out infinite;
}
@keyframes pulse { 0%, 100% { opacity: 1; } 50% { opacity: 0.4; } }

.hero-title { margin-bottom: 20px; }
.title-line { display: block; font-size: clamp(32px, 6vw, 52px); font-weight: 900; line-height: 1.2; letter-spacing: -1px; }
.title-gradient {
    background: var(--gradient); -webkit-background-clip: text; -webkit-text-fill-color: transparent;
    background-clip: text;
}
.hero-subtitle { font-size: 16px; color: var(--text-secondary); line-height: 1.8; margin-bottom: 32px; }

.hero-stats {
    display: flex; align-items: center; gap: 24px;
    padding: 20px 28px; border-radius: var(--radius);
    background: var(--bg-card); box-shadow: var(--shadow-md);
    margin-bottom: 36px; border: 1px solid var(--border);
}
.stat-item { text-align: center; }
.stat-number { font-size: 28px; font-weight: 900; color: var(--primary-dark); }
.stat-unit { font-size: 14px; font-weight: 700; color: var(--primary); }
.stat-label { display: block; font-size: 12px; color: var(--text-light); margin-top: 2px; }
.stat-divider { width: 1px; height: 40px; background: var(--border); }

.hero-actions { display: flex; gap: 16px; flex-wrap: wrap; }
.btn-primary {
    display: inline-flex; align-items: center; gap: 8px;
    padding: 14px 36px; border-radius: 50px;
    background: var(--gradient); color: #fff;
    text-decoration: none; font-weight: 700; font-size: 16px;
    box-shadow: var(--shadow-glow);
    transition: all 0.3s ease;
}
.btn-primary:hover { transform: translateY(-3px); box-shadow: 0 12px 45px rgba(0,188,212,0.35); }
.btn-secondary {
    display: inline-flex; align-items: center; gap: 6px;
    padding: 14px 28px; border-radius: 50px;
    background: transparent; color: var(--text-secondary);
    text-decoration: none; font-weight: 500; font-size: 15px;
    border: 1.5px solid var(--border);
    transition: all 0.3s ease;
}
.btn-secondary:hover { border-color: var(--primary-light); color: var(--primary-dark); }

.hero-image {
    position: relative; z-index: 2;
    max-width: 480px; flex: 1; min-width: 280px;
    opacity: 0; transform: translateY(40px);
    transition: all 1s cubic-bezier(0.4,0,0.2,1) 0.3s;
}
.hero.visible .hero-image { opacity: 1; transform: translateY(0); }
.phone-glow {
    position: absolute; top: 50%; left: 50%; transform: translate(-50%, -50%);
    width: 80%; height: 80%; border-radius: 50%;
    background: radial-gradient(circle, rgba(0,188,212,0.12) 0%, transparent 70%);
    filter: blur(40px);
}
.hero-img { position: relative; z-index: 1; border-radius: var(--radius-lg); }

/* ===== 通用区块 ===== */
.section-container { max-width: 1200px; margin: 0 auto; padding: 0 24px; }
.section-header { text-align: center; margin-bottom: 60px; }
.section-tag {
    display: inline-block; padding: 6px 18px; border-radius: 50px;
    background: rgba(0,188,212,0.08); color: var(--primary-dark);
    font-size: 13px; font-weight: 600; margin-bottom: 16px;
    letter-spacing: 1px;
}
.section-title { font-size: clamp(26px, 4vw, 38px); font-weight: 800; margin-bottom: 12px; color: var(--text); }
.section-desc { font-size: 16px; color: var(--text-secondary); }

/* ===== 产品特色 ===== */
.features { padding: 100px 0; background: var(--bg-soft); }
.features-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 24px;
}
.feature-card {
    padding: 36px 28px; border-radius: var(--radius-lg);
    background: var(--bg-card); border: 1px solid var(--border);
    transition: all 0.4s cubic-bezier(0.4,0,0.2,1);
    opacity: 0; transform: translateY(30px);
}
.feature-card.visible { opacity: 1; transform: translateY(0); }
.feature-card:hover { transform: translateY(-6px); box-shadow: var(--shadow-lg); border-color: rgba(0,188,212,0.2); }

.feature-card-large { grid-column: span 3; display: flex; align-items: center; gap: 40px; padding: 48px 40px; }
.feature-card-large .feature-visual { flex: 1; max-width: 400px; }
.feature-card-large .feature-visual img { border-radius: var(--radius); }

.feature-icon {
    width: 56px; height: 56px; border-radius: 16px;
    display: flex; align-items: center; justify-content: center;
    margin-bottom: 20px;
}
.icon-gradient-1 { background: linear-gradient(135deg, rgba(0,188,212,0.12), rgba(38,198,218,0.06)); color: #00BCD4; }
.icon-gradient-2 { background: linear-gradient(135deg, rgba(76,175,80,0.12), rgba(129,199,132,0.06)); color: #4CAF50; }
.icon-gradient-3 { background: linear-gradient(135deg, rgba(33,150,243,0.12), rgba(100,181,246,0.06)); color: #2196F3; }
.icon-gradient-4 { background: linear-gradient(135deg, rgba(255,152,0,0.12), rgba(255,183,77,0.06)); color: #FF9800; }
.icon-gradient-5 { background: linear-gradient(135deg, rgba(156,39,176,0.12), rgba(186,104,200,0.06)); color: #9C27B0; }

.feature-card h3 { font-size: 19px; font-weight: 700; margin-bottom: 10px; color: var(--text); }
.feature-card p { font-size: 14px; color: var(--text-secondary); line-height: 1.7; }

/* ===== 安全保障 ===== */
.security { padding: 100px 0; background: var(--bg); }
.security-layout { display: flex; align-items: center; gap: 60px; flex-wrap: wrap; }
.security-image {
    flex: 1; min-width: 280px; max-width: 450px;
    opacity: 0; transform: translateX(-30px);
    transition: all 0.8s cubic-bezier(0.4,0,0.2,1);
}
.security-image.visible { opacity: 1; transform: translateX(0); }
.security-image img { border-radius: var(--radius-lg); }
.security-content { flex: 1; min-width: 320px; }
.security-list { margin-top: 32px; display: flex; flex-direction: column; gap: 20px; }
.security-item {
    display: flex; align-items: flex-start; gap: 16px;
    padding: 20px; border-radius: var(--radius);
    background: var(--bg-soft); border: 1px solid var(--border);
    opacity: 0; transform: translateX(20px);
    transition: all 0.5s cubic-bezier(0.4,0,0.2,1);
}
.security-item.visible { opacity: 1; transform: translateX(0); }
.security-item:nth-child(2).visible { transition-delay: 0.1s; }
.security-item:nth-child(3).visible { transition-delay: 0.2s; }
.security-item:nth-child(4).visible { transition-delay: 0.3s; }
.security-check {
    width: 36px; height: 36px; border-radius: 50%;
    background: var(--gradient); color: #fff;
    display: flex; align-items: center; justify-content: center;
    font-weight: 700; font-size: 16px; flex-shrink: 0;
}
.security-item h4 { font-size: 16px; font-weight: 700; margin-bottom: 4px; color: var(--text); }
.security-item p { font-size: 13px; color: var(--text-secondary); }

/* ===== 使用流程 ===== */
.process { padding: 100px 0; background: var(--bg-soft); }
.process-steps { display: flex; align-items: center; justify-content: center; gap: 0; flex-wrap: wrap; }
.step-card {
    text-align: center; padding: 40px 32px;
    background: var(--bg-card); border-radius: var(--radius-lg);
    border: 1px solid var(--border);
    min-width: 220px; flex: 1; max-width: 300px;
    opacity: 0; transform: translateY(30px);
    transition: all 0.5s cubic-bezier(0.4,0,0.2,1);
}
.step-card.visible { opacity: 1; transform: translateY(0); }
.step-card:nth-child(3).visible { transition-delay: 0.15s; }
.step-card:nth-child(5).visible { transition-delay: 0.3s; }
.step-card:hover { transform: translateY(-4px); box-shadow: var(--shadow-md); }
.step-number {
    font-size: 48px; font-weight: 900; line-height: 1;
    background: var(--gradient); -webkit-background-clip: text; -webkit-text-fill-color: transparent;
    background-clip: text; margin-bottom: 20px;
}
.step-card h3 { font-size: 18px; font-weight: 700; margin-bottom: 10px; }
.step-card p { font-size: 14px; color: var(--text-secondary); line-height: 1.6; }
.step-connector { width: 60px; height: 2px; background: var(--gradient); flex-shrink: 0; }

/* ===== 下载区域 ===== */
.download { padding: 100px 0 120px; background: var(--bg); }
.download-card {
    padding: 64px 40px; border-radius: var(--radius-xl); text-align: center;
    background: linear-gradient(135deg, #f0fafb 0%, #e0f7fa 50%, #f0fafb 100%);
    border: 1px solid rgba(0,188,212,0.15);
    position: relative; overflow: hidden;
    opacity: 0; transform: translateY(30px);
    transition: all 0.8s cubic-bezier(0.4,0,0.2,1);
}
.download-card.visible { opacity: 1; transform: translateY(0); }
.download-logo { width: 80px; height: 80px; border-radius: 20px; margin: 0 auto 24px; box-shadow: var(--shadow-md); }
.download-card h2 { font-size: 30px; font-weight: 800; margin-bottom: 10px; color: var(--text); }
.download-card > .download-content > p:first-of-type { font-size: 16px; color: var(--text-secondary); margin-bottom: 32px; }
.download-buttons { display: flex; gap: 16px; justify-content: center; flex-wrap: wrap; margin-bottom: 24px; }
.download-btn {
    display: flex; align-items: center; gap: 12px;
    padding: 16px 32px; border-radius: 16px;
    text-decoration: none; font-size: 15px;
    transition: all 0.3s ease; min-width: 200px;
}
.download-btn small { display: block; font-size: 11px; opacity: 0.8; }
.download-btn strong { display: block; font-size: 16px; }
.android-btn {
    background: var(--text); color: #fff;
    box-shadow: 0 4px 20px rgba(26,35,50,0.2);
}
.android-btn:hover { transform: translateY(-3px); box-shadow: 0 8px 30px rgba(26,35,50,0.3); }
.ios-btn {
    background: var(--bg-card); color: var(--text);
    border: 1.5px solid var(--border);
}
.ios-btn:hover { transform: translateY(-3px); box-shadow: var(--shadow-md); border-color: var(--primary-light); }
.download-note { font-size: 13px; color: var(--text-light); display: flex; align-items: center; justify-content: center; gap: 6px; }

/* ===== 页脚 ===== */
.footer { padding: 32px 0; background: var(--bg-soft); border-top: 1px solid var(--border); }
.footer-content { display: flex; align-items: center; justify-content: space-between; flex-wrap: wrap; gap: 16px; }
.footer-brand { display: flex; align-items: center; gap: 8px; font-weight: 700; font-size: 15px; color: var(--text); }
.footer-logo { width: 28px; height: 28px; border-radius: 8px; }
.footer-copyright { font-size: 13px; color: var(--text-light); }

/* ===== 弹窗 ===== */
.modal-overlay {
    position: fixed; inset: 0; z-index: 9999;
    background: rgba(0,0,0,0.5); backdrop-filter: blur(8px);
    display: flex; align-items: center; justify-content: center;
    opacity: 0; visibility: hidden;
    transition: all 0.3s ease; padding: 24px;
}
.modal-overlay.active { opacity: 1; visibility: visible; }
.modal-card {
    background: var(--bg-card); border-radius: var(--radius-xl);
    padding: 40px 32px; max-width: 400px; width: 100%;
    text-align: center; position: relative;
    transform: translateY(20px) scale(0.95);
    transition: all 0.4s cubic-bezier(0.4,0,0.2,1);
}
.modal-overlay.active .modal-card { transform: translateY(0) scale(1); }
.modal-close {
    position: absolute; top: 16px; right: 16px;
    width: 32px; height: 32px; border-radius: 50%;
    border: none; background: var(--bg-soft); cursor: pointer;
    font-size: 20px; color: var(--text-light);
    display: flex; align-items: center; justify-content: center;
    transition: all 0.2s;
}
.modal-close:hover { background: var(--border); color: var(--text); }
.modal-header-tag {
    display: inline-block; padding: 4px 16px; border-radius: 50px;
    background: rgba(0,188,212,0.1); color: var(--primary-dark);
    font-size: 12px; font-weight: 600; margin-bottom: 16px;
    letter-spacing: 1px;
}
.modal-logo { width: 72px; height: 72px; border-radius: 18px; margin: 0 auto 20px; box-shadow: var(--shadow-md); }
.modal-card h3 { font-size: 20px; font-weight: 700; margin-bottom: 12px; color: var(--text); }
.modal-card > p { font-size: 14px; color: var(--text-secondary); margin-bottom: 8px; line-height: 1.6; }
.modal-path {
    padding: 14px 20px; border-radius: 12px;
    background: var(--bg-soft); border: 1px solid var(--border);
    font-size: 15px; font-weight: 600; color: var(--text);
    margin: 12px 0 8px; letter-spacing: 0.5px;
}
.modal-path span {
    color: var(--primary-dark); font-weight: 700;
}
.modal-path-hint {
    font-size: 13px; color: var(--text-light); margin-bottom: 24px;
}
.modal-btn-group { display: flex; flex-direction: column; gap: 10px; }
.modal-install-btn { width: 100%; justify-content: center; }
.btn-cancel {
    width: 100%; padding: 12px; border-radius: 50px;
    border: 1.5px solid var(--border); background: transparent;
    color: var(--text-secondary); font-size: 15px; font-weight: 500;
    cursor: pointer; transition: all 0.2s;
    font-family: inherit;
}
.btn-cancel:hover { border-color: var(--text-light); color: var(--text); }

/* ===== 安卓安装引导 ===== */
.android-guide-steps {
    display: flex; flex-direction: column; gap: 10px;
    margin: 16px 0; text-align: left;
}
.guide-step {
    display: flex; align-items: flex-start; gap: 12px;
    padding: 12px 16px; border-radius: 12px;
    background: var(--bg-soft); font-size: 14px;
    line-height: 1.5;
}
.guide-step strong { color: var(--primary-dark); }
.guide-num {
    width: 22px; height: 22px; border-radius: 50%;
    background: var(--gradient); color: #fff;
    display: flex; align-items: center; justify-content: center;
    font-size: 12px; font-weight: 700; flex-shrink: 0;
    margin-top: 1px;
}
.guide-tip {
    display: flex; align-items: center; justify-content: center; gap: 8px;
    padding: 10px 16px; border-radius: 10px;
    background: rgba(76,175,80,0.08); border: 1px solid rgba(76,175,80,0.15);
    font-size: 13px; color: #2E7D32; margin-bottom: 20px;
}
.tip-icon { font-size: 16px; }

/* ===== 响应式 ===== */
@media (max-width: 768px) {
    .hero { flex-direction: column; text-align: center; padding: 100px 20px 60px; min-height: auto; }
    .hero-content { max-width: 100%; }
    .hero-badge { margin: 0 auto 24px; }
    .hero-stats { flex-direction: row; gap: 16px; justify-content: center; padding: 16px 20px; }
    .stat-number { font-size: 22px; }
    .hero-actions { justify-content: center; }
    .hero-image { max-width: 320px; }
    .features-grid { grid-template-columns: 1fr; }
    .feature-card-large { grid-column: span 1; flex-direction: column; padding: 32px 24px; }
    .feature-card-large .feature-visual { max-width: 100%; }
    .security-layout { flex-direction: column; }
    .security-image { max-width: 100%; }
    .process-steps { flex-direction: column; gap: 16px; }
    .step-connector { width: 2px; height: 30px; }
    .step-card { max-width: 100%; }
    .download-card { padding: 40px 24px; }
    .download-card h2 { font-size: 24px; }
    .download-buttons { flex-direction: column; align-items: center; }
    .download-btn { width: 100%; max-width: 280px; justify-content: center; }
    .footer-content { justify-content: center; text-align: center; }
}

@media (max-width: 480px) {
    .hero-stats { flex-wrap: wrap; }
    .stat-divider { display: none; }
}