/* Feishu Official Website - Global Styles */
/* SEO-optimized, responsive, brand-compliant */

:root {
    --brand-blue: #3370FF;
    --brand-blue-hover: #2860E6;
    --brand-blue-light: #E8F0FE;
    --text-dark: #1D1D1F;
    --text-body: #5A5A6E;
    --text-light: #86868B;
    --bg-white: #FFFFFF;
    --bg-light: #F5F6F7;
    --bg-dark: #1A1A2E;
    --border-color: #E5E6EB;
    --shadow-sm: 0 2px 8px rgba(0,0,0,0.06);
    --shadow-md: 0 4px 16px rgba(0,0,0,0.1);
    --shadow-lg: 0 8px 32px rgba(0,0,0,0.12);
    --radius-sm: 8px;
    --radius-md: 12px;
    --radius-lg: 16px;
    --transition: all 0.3s ease-out;
    --max-width: 1200px;
}

* { margin: 0; padding: 0; box-sizing: border-box; }

html { scroll-behavior: smooth; }

body {
    font-family: -apple-system, BlinkMacSystemFont, "PingFang SC", "Microsoft YaHei", "Helvetica Neue", Arial, sans-serif;
    color: var(--text-body);
    line-height: 1.7;
    font-size: 16px;
    background: var(--bg-white);
}

a { color: var(--brand-blue); text-decoration: none; transition: var(--transition); }
a:hover { color: var(--brand-blue-hover); }

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

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

/* Typography */
h1 { font-size: 56px; font-weight: 700; color: var(--text-dark); line-height: 1.2; letter-spacing: -0.5px; }
h2 { font-size: 40px; font-weight: 700; color: var(--text-dark); line-height: 1.3; }
h3 { font-size: 28px; font-weight: 600; color: var(--text-dark); line-height: 1.4; }
h4 { font-size: 22px; font-weight: 600; color: var(--text-dark); line-height: 1.4; }
p { margin-bottom: 16px; }

/* Navigation */
.nav {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    z-index: 1000;
    background: rgba(255,255,255,0.95);
    backdrop-filter: blur(10px);
    border-bottom: 1px solid var(--border-color);
    height: 64px;
    display: flex;
    align-items: center;
}

.nav .container {
    display: flex;
    align-items: center;
    justify-content: space-between;
    width: 100%;
}

.nav-logo {
    display: flex;
    align-items: center;
    gap: 8px;
    font-size: 22px;
    font-weight: 700;
    color: var(--text-dark);
}

.nav-logo img { height: 32px; }

.nav-links { display: flex; align-items: center; gap: 32px; list-style: none; }
.nav-links li { position: relative; }
.nav-links a { color: var(--text-dark); font-size: 15px; font-weight: 500; padding: 8px 0; }
.nav-links a:hover { color: var(--brand-blue); }

/* Dropdown */
.dropdown { position: relative; }
.dropdown-menu {
    display: none;
    position: absolute;
    top: 100%;
    left: -20px;
    background: var(--bg-white);
    border-radius: var(--radius-md);
    box-shadow: var(--shadow-lg);
    padding: 12px 0;
    min-width: 220px;
    z-index: 100;
}
.dropdown:hover .dropdown-menu { display: block; }
.dropdown-menu a {
    display: block;
    padding: 10px 20px;
    color: var(--text-body);
    font-size: 14px;
}
.dropdown-menu a:hover { background: var(--bg-light); color: var(--brand-blue); }

.nav-actions { display: flex; align-items: center; gap: 16px; }

/* Buttons */
.btn {
    display: inline-block;
    padding: 12px 28px;
    border-radius: 8px;
    font-size: 15px;
    font-weight: 600;
    text-align: center;
    cursor: pointer;
    transition: var(--transition);
    border: none;
    line-height: 1.4;
}

.btn-primary {
    background: var(--brand-blue);
    color: #fff;
}
.btn-primary:hover {
    background: var(--brand-blue-hover);
    color: #fff;
    transform: translateY(-2px);
    box-shadow: 0 4px 12px rgba(51,112,255,0.3);
}

.btn-outline {
    background: transparent;
    color: var(--brand-blue);
    border: 2px solid var(--brand-blue);
}
.btn-outline:hover {
    background: var(--brand-blue);
    color: #fff;
    transform: translateY(-2px);
}

.btn-ghost {
    background: transparent;
    color: var(--text-dark);
    padding: 8px 16px;
}
.btn-ghost:hover { color: var(--brand-blue); }

.btn-lg { padding: 16px 40px; font-size: 17px; border-radius: 10px; }
.btn-sm { padding: 8px 20px; font-size: 14px; }

/* Hero Section */
.hero {
    padding: 160px 0 100px;
    background: linear-gradient(135deg, #E8F0FE 0%, #F0E6FF 50%, #E8F4FD 100%);
    text-align: center;
    position: relative;
    overflow: hidden;
}

.hero h1 { font-size: 64px; margin-bottom: 24px; }
.hero .subtitle { font-size: 20px; color: var(--text-body); max-width: 680px; margin: 0 auto 40px; line-height: 1.8; }
.hero-actions { display: flex; gap: 16px; justify-content: center; flex-wrap: wrap; }
.hero-trust { margin-top: 48px; display: flex; gap: 40px; justify-content: center; flex-wrap: wrap; }
.hero-trust-item { text-align: center; }
.hero-trust-item .number { font-size: 36px; font-weight: 700; color: var(--brand-blue); }
.hero-trust-item .label { font-size: 14px; color: var(--text-light); }

.scroll-hint {
    position: absolute;
    bottom: 30px;
    left: 50%;
    transform: translateX(-50%);
    color: var(--text-light);
    font-size: 14px;
    animation: bounce 2s infinite;
}

@keyframes bounce {
    0%, 100% { transform: translateX(-50%) translateY(0); }
    50% { transform: translateX(-50%) translateY(-8px); }
}

/* Section Common */
.section { padding: 100px 0; }
.section-light { background: var(--bg-light); }
.section-dark { background: var(--bg-dark); color: #fff; }
.section-dark h2, .section-dark h3, .section-dark h4 { color: #fff; }
.section-dark p { color: rgba(255,255,255,0.8); }

.section-header { text-align: center; margin-bottom: 60px; }
.section-header h2 { margin-bottom: 16px; }
.section-header p { font-size: 18px; max-width: 600px; margin: 0 auto; }

/* Solution Cards */
.cards-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: 24px;
}

.card {
    background: var(--bg-white);
    border-radius: var(--radius-md);
    padding: 32px;
    border: 1px solid var(--border-color);
    transition: var(--transition);
}
.card:hover {
    transform: translateY(-4px);
    box-shadow: var(--shadow-md);
    border-color: var(--brand-blue);
}

.card-icon {
    width: 56px;
    height: 56px;
    border-radius: 12px;
    background: var(--brand-blue-light);
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 28px;
    margin-bottom: 20px;
}

.card h4 { margin-bottom: 12px; }
.card p { font-size: 15px; color: var(--text-body); margin-bottom: 16px; }
.card-link { font-size: 14px; font-weight: 600; color: var(--brand-blue); }
.card-link:hover { color: var(--brand-blue-hover); }

/* Feature Blocks */
.feature-block {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 60px;
    align-items: center;
    margin-bottom: 80px;
}
.feature-block:nth-child(even) .feature-visual { order: -1; }

.feature-text h3 { margin-bottom: 16px; }
.feature-text p { font-size: 16px; line-height: 1.8; margin-bottom: 20px; }
.feature-list { list-style: none; margin-bottom: 24px; }
.feature-list li {
    padding: 8px 0;
    padding-left: 28px;
    position: relative;
    font-size: 15px;
}
.feature-list li::before {
    content: "\2713";
    position: absolute;
    left: 0;
    color: var(--brand-blue);
    font-weight: 700;
}

.feature-visual {
    background: var(--bg-light);
    border-radius: var(--radius-lg);
    padding: 40px;
    text-align: center;
    min-height: 360px;
    display: flex;
    align-items: center;
    justify-content: center;
    border: 1px solid var(--border-color);
}

/* Logo Wall */
.logo-wall {
    display: flex;
    flex-wrap: wrap;
    gap: 32px;
    justify-content: center;
    align-items: center;
    margin-bottom: 48px;
}

.logo-wall-item {
    width: 140px;
    height: 60px;
    display: flex;
    align-items: center;
    justify-content: center;
    background: var(--bg-white);
    border-radius: var(--radius-sm);
    border: 1px solid var(--border-color);
    font-weight: 600;
    color: var(--text-light);
    font-size: 15px;
    transition: var(--transition);
}
.logo-wall-item:hover {
    color: var(--brand-blue);
    border-color: var(--brand-blue);
    box-shadow: var(--shadow-sm);
}

/* Case Carousel */
.case-carousel {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(350px, 1fr));
    gap: 24px;
}

.case-card {
    background: var(--bg-white);
    border-radius: var(--radius-md);
    padding: 32px;
    border: 1px solid var(--border-color);
    transition: var(--transition);
}
.case-card:hover { transform: translateY(-4px); box-shadow: var(--shadow-md); }
.case-card .case-quote { font-style: italic; font-size: 16px; line-height: 1.8; margin-bottom: 20px; color: var(--text-dark); }
.case-card .case-author { font-size: 14px; color: var(--text-light); }
.case-card .case-metric { font-size: 32px; font-weight: 700; color: var(--brand-blue); margin-bottom: 8px; }

/* Security Grid */
.security-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 24px;
}

.security-item {
    text-align: center;
    padding: 32px 24px;
    background: var(--bg-white);
    border-radius: var(--radius-md);
    border: 1px solid var(--border-color);
}
.security-item .icon { font-size: 40px; margin-bottom: 16px; }
.security-item h4 { margin-bottom: 8px; font-size: 18px; }
.security-item p { font-size: 14px; color: var(--text-body); }

/* Data Stats */
.stats-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 32px;
    text-align: center;
}

.stat-item .stat-number { font-size: 48px; font-weight: 700; color: #fff; margin-bottom: 8px; }
.stat-item .stat-label { font-size: 16px; color: rgba(255,255,255,0.7); }

/* Integration */
.integration-visual {
    text-align: center;
    padding: 60px 0;
}
.integration-center {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    width: 100px;
    height: 100px;
    border-radius: 50%;
    background: var(--brand-blue);
    color: #fff;
    font-size: 20px;
    font-weight: 700;
    margin-bottom: 40px;
}
.integration-icons {
    display: flex;
    flex-wrap: wrap;
    gap: 20px;
    justify-content: center;
}
.integration-icon {
    width: 72px;
    height: 72px;
    border-radius: 16px;
    background: var(--bg-white);
    border: 1px solid var(--border-color);
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 13px;
    font-weight: 600;
    color: var(--text-body);
    transition: var(--transition);
}
.integration-icon:hover { transform: translateY(-4px); box-shadow: var(--shadow-md); color: var(--brand-blue); }

/* Pricing */
.pricing-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 24px;
    max-width: 1000px;
    margin: 0 auto;
}

.pricing-card {
    background: var(--bg-white);
    border-radius: var(--radius-lg);
    padding: 40px 32px;
    border: 2px solid var(--border-color);
    text-align: center;
    transition: var(--transition);
    position: relative;
}
.pricing-card:hover { transform: translateY(-4px); box-shadow: var(--shadow-lg); }
.pricing-card.featured { border-color: var(--brand-blue); }
.pricing-card.featured::before {
    content: "最受欢迎";
    position: absolute;
    top: -14px;
    left: 50%;
    transform: translateX(-50%);
    background: var(--brand-blue);
    color: #fff;
    padding: 4px 20px;
    border-radius: 20px;
    font-size: 13px;
    font-weight: 600;
}

.pricing-card h3 { margin-bottom: 8px; }
.pricing-card .price { font-size: 40px; font-weight: 700; color: var(--text-dark); margin-bottom: 8px; }
.pricing-card .price-note { font-size: 14px; color: var(--text-light); margin-bottom: 24px; }
.pricing-card .features-list { list-style: none; text-align: left; margin-bottom: 32px; }
.pricing-card .features-list li { padding: 10px 0; border-bottom: 1px solid var(--border-color); font-size: 15px; padding-left: 24px; position: relative; }
.pricing-card .features-list li::before { content: "\2713"; position: absolute; left: 0; color: var(--brand-blue); font-weight: 700; }

/* Final CTA */
.final-cta {
    padding: 100px 0;
    background: linear-gradient(135deg, var(--brand-blue) 0%, #5B8DEF 100%);
    text-align: center;
    color: #fff;
}
.final-cta h2 { color: #fff; margin-bottom: 16px; }
.final-cta p { font-size: 18px; color: rgba(255,255,255,0.9); margin-bottom: 32px; }
.final-cta .btn-primary { background: #fff; color: var(--brand-blue); }
.final-cta .btn-primary:hover { background: #f0f0f0; }

/* FAQ Section */
.faq-section { padding: 80px 0; }
.faq-grid { max-width: 900px; margin: 0 auto; }
.faq-item { border-bottom: 1px solid var(--border-color); padding: 24px 0; }
.faq-item h4 { margin-bottom: 12px; font-size: 18px; color: var(--text-dark); }
.faq-answer { padding-left: 0; }
.faq-answer p { font-size: 15px; line-height: 1.8; margin-bottom: 8px; }
.faq-step { display: flex; gap: 12px; margin-bottom: 8px; }
.faq-step-num {
    flex-shrink: 0;
    width: 24px;
    height: 24px;
    border-radius: 50%;
    background: var(--brand-blue);
    color: #fff;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 13px;
    font-weight: 600;
    margin-top: 2px;
}

/* Footer */
.footer {
    background: #1A1A2E;
    color: rgba(255,255,255,0.7);
    padding: 60px 0 30px;
}

.footer-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(180px, 1fr));
    gap: 40px;
    margin-bottom: 40px;
}

.footer-col h4 { color: #fff; font-size: 16px; margin-bottom: 16px; }
.footer-col ul { list-style: none; }
.footer-col ul li { margin-bottom: 10px; }
.footer-col ul li a { color: rgba(255,255,255,0.6); font-size: 14px; }
.footer-col ul li a:hover { color: #fff; }

.footer-bottom {
    border-top: 1px solid rgba(255,255,255,0.1);
    padding-top: 24px;
    display: flex;
    justify-content: space-between;
    align-items: center;
    flex-wrap: wrap;
    gap: 16px;
    font-size: 13px;
}

.footer-social { display: flex; gap: 16px; }
.footer-social a { color: rgba(255,255,255,0.6); font-size: 14px; }
.footer-social a:hover { color: #fff; }

/* Page Header (for sub-pages) */
.page-header {
    padding: 140px 0 60px;
    background: linear-gradient(135deg, #E8F0FE 0%, #F0E6FF 100%);
    text-align: center;
}
.page-header h1 { font-size: 48px; margin-bottom: 16px; }
.page-header p { font-size: 18px; max-width: 600px; margin: 0 auto; }

/* Breadcrumb */
.breadcrumb { padding: 16px 0; font-size: 14px; color: var(--text-light); }
.breadcrumb a { color: var(--text-light); }
.breadcrumb a:hover { color: var(--brand-blue); }
.breadcrumb span { margin: 0 8px; }

/* Responsive */
@media (max-width: 1024px) {
    h1 { font-size: 42px; }
    h2 { font-size: 32px; }
    .hero h1 { font-size: 48px; }
    .feature-block { grid-template-columns: 1fr; gap: 32px; }
    .feature-block:nth-child(even) .feature-visual { order: 0; }
}

@media (max-width: 768px) {
    h1 { font-size: 32px; }
    h2 { font-size: 26px; }
    h3 { font-size: 22px; }
    .hero { padding: 120px 0 60px; }
    .hero h1 { font-size: 36px; }
    .hero .subtitle { font-size: 17px; }
    .section { padding: 60px 0; }
    .nav-links { display: none; }
    .cards-grid { grid-template-columns: 1fr; }
    .pricing-grid { grid-template-columns: 1fr; }
    .stats-grid { grid-template-columns: repeat(2, 1fr); }
    .hero-trust { gap: 24px; }
    .footer-grid { grid-template-columns: repeat(2, 1fr); }
}

@media (max-width: 375px) {
    .container { padding: 0 16px; }
    .hero h1 { font-size: 28px; }
    .hero-actions { flex-direction: column; align-items: center; }
}