/* ===== Reset & Base ===== */
*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }

:root {
    --primary: #1a56db;
    --primary-dark: #1e40af;
    --primary-light: #e8f0fe;
    --accent: #f97316;
    --text: #1a1a2e;
    --text-secondary: #555;
    --bg: #f8fafc;
    --white: #fff;
    --border: #e2e8f0;
    --radius: 12px;
    --shadow: 0 2px 12px rgba(0,0,0,.08);
    --shadow-lg: 0 8px 30px rgba(0,0,0,.12);
    --max-width: 1200px;
}

html { scroll-behavior: smooth; }

body {
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", "Helvetica Neue", Arial, sans-serif;
    color: var(--text);
    background: var(--bg);
    line-height: 1.7;
    font-size: 16px;
    overflow-x: hidden;
}

a { color: var(--primary); text-decoration: none; }
a:hover { color: var(--primary-dark); }
img { max-width: 100%; height: auto; }

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

.section-title {
    font-size: 32px; font-weight: 700; text-align: center;
    margin-bottom: 12px; color: var(--text);
}
.section-desc {
    text-align: center; color: var(--text-secondary); font-size: 18px;
    margin-bottom: 48px;
}

/* ===== Buttons ===== */
.btn {
    display: inline-block; padding: 10px 24px; border-radius: 8px;
    font-size: 15px; font-weight: 600; cursor: pointer; border: 2px solid transparent;
    transition: all .2s; text-align: center; white-space: nowrap;
}
.btn-primary {
    background: var(--primary); color: var(--white); border-color: var(--primary);
}
.btn-primary:hover { background: var(--primary-dark); color: var(--white); }
.btn-outline {
    background: transparent; color: var(--primary); border-color: var(--primary);
}
.btn-outline:hover { background: var(--primary); color: var(--white); }
.btn-ghost {
    background: transparent; color: var(--text); border-color: var(--border);
}
.btn-ghost:hover { background: var(--white); }
.btn-lg { padding: 14px 36px; font-size: 17px; }
.btn-block { display: block; width: 100%; }

/* ===== Header ===== */
.header {
    position: sticky; top: 0; z-index: 100;
    background: rgba(255,255,255,.95); backdrop-filter: blur(10px);
    border-bottom: 1px solid var(--border); padding: 0;
}
.header-inner {
    display: flex; align-items: center; justify-content: space-between;
    height: 64px; gap: 20px;
}
.logo {
    display: flex; align-items: center; gap: 8px;
    font-size: 22px; font-weight: 800; color: var(--primary); flex-shrink: 0;
}
.logo-icon { font-size: 26px; }
.logo-text { background: linear-gradient(135deg, var(--primary), var(--accent)); -webkit-background-clip: text; -webkit-text-fill-color: transparent; }

.nav { display: flex; gap: 8px; flex-wrap: wrap; }
.nav-link {
    padding: 8px 14px; color: var(--text-secondary); font-size: 14px;
    border-radius: 6px; transition: all .2s; font-weight: 500;
}
.nav-link:hover, .nav-link.active { color: var(--primary); background: var(--primary-light); }

.header-actions { display: flex; gap: 10px; flex-shrink: 0; }

/* ===== Hero ===== */
.hero {
    background: linear-gradient(160deg, #eff6ff 0%, #f8fafc 40%, #fff7ed 100%);
    padding: 60px 0 80px;
}
.hero-inner {
    display: grid; grid-template-columns: 1.2fr 1fr; gap: 60px; align-items: center;
}
.hero-title {
    font-size: 44px; font-weight: 800; line-height: 1.3; margin-bottom: 16px;
}
.hero-title .highlight {
    background: linear-gradient(135deg, var(--primary), #7c3aed);
    -webkit-background-clip: text; -webkit-text-fill-color: transparent;
}
.hero-subtitle { font-size: 18px; color: var(--text-secondary); margin-bottom: 32px; line-height: 1.8; }
.hero-subtitle strong { color: var(--accent); }

.hero-stats {
    display: flex; gap: 30px; margin-bottom: 36px; flex-wrap: wrap;
}
.stat-item { text-align: center; }
.stat-number { display: block; font-size: 28px; font-weight: 800; color: var(--primary); }
.stat-label { font-size: 14px; color: var(--text-secondary); }

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

/* Hero Mockup */
.hero-mockup {
    background: var(--white); border-radius: 16px; box-shadow: var(--shadow-lg);
    overflow: hidden; border: 1px solid var(--border);
}
.mockup-header {
    background: #f1f5f9; padding: 12px 16px; display: flex; gap: 6px;
}
.mockup-dot { width: 10px; height: 10px; border-radius: 50%; background: #cbd5e1; }
.mockup-body { padding: 16px; }
.mockup-search { display: flex; gap: 8px; margin-bottom: 12px; }
.mockup-search input {
    flex: 1; padding: 10px 14px; border: 1px solid var(--border); border-radius: 8px;
    font-size: 13px; outline: none;
}
.mockup-search button {
    padding: 10px 18px; background: var(--primary); color: var(--white);
    border: none; border-radius: 8px; font-size: 13px; cursor: pointer;
}
.mockup-card {
    background: var(--bg); border-radius: 8px; padding: 12px; margin-bottom: 8px;
}
.mockup-company { font-size: 14px; font-weight: 600; margin-bottom: 4px; }
.mockup-info { font-size: 12px; color: var(--text-secondary); }
.mockup-phone { font-size: 13px; color: var(--primary); font-weight: 600; margin-top: 4px; }

/* ===== Pain Points ===== */
.pain-points { padding: 80px 0; background: var(--white); }
.pain-grid {
    display: grid; grid-template-columns: repeat(4, 1fr); gap: 24px;
}
.pain-card {
    text-align: center; padding: 36px 24px; border-radius: var(--radius);
    border: 1px solid var(--border); transition: all .3s;
}
.pain-card:hover { box-shadow: var(--shadow-lg); transform: translateY(-4px); }
.pain-icon { font-size: 40px; margin-bottom: 16px; }
.pain-card h3 { font-size: 20px; margin-bottom: 12px; color: var(--text); }
.pain-card p { font-size: 14px; color: var(--text-secondary); line-height: 1.8; }

/* ===== Features ===== */
.features { padding: 80px 0; background: var(--bg); }
.features-grid {
    display: grid; grid-template-columns: repeat(3, 1fr); gap: 28px;
}
.feature-card {
    background: var(--white); border-radius: var(--radius); padding: 36px 28px;
    border: 1px solid var(--border); transition: all .3s;
}
.feature-card:hover { box-shadow: var(--shadow-lg); }
.feature-icon { margin-bottom: 20px; }
.feature-card h3 { font-size: 22px; margin-bottom: 14px; color: var(--text); }
.feature-card p { font-size: 15px; color: var(--text-secondary); line-height: 1.8; margin-bottom: 16px; }
.feature-list { list-style: none; }
.feature-list li {
    padding: 6px 0; font-size: 14px; color: var(--text-secondary);
    padding-left: 20px; position: relative;
}
.feature-list li::before {
    content: "✓"; position: absolute; left: 0; color: #10b981; font-weight: 700;
}

/* ===== Data Coverage ===== */
.data-coverage { padding: 80px 0; background: var(--white); }
.coverage-grid {
    display: grid; grid-template-columns: repeat(3, 1fr); gap: 24px;
}
.coverage-card {
    text-align: center; padding: 40px 24px; border-radius: var(--radius);
    background: linear-gradient(135deg, var(--primary-light), #f0f9ff);
    border: 1px solid #dbeafe; transition: all .3s;
}
.coverage-card:hover { transform: translateY(-4px); box-shadow: var(--shadow); }
.coverage-card h3 { font-size: 36px; color: var(--primary); margin-bottom: 8px; }
.coverage-card p { font-size: 17px; font-weight: 600; margin-bottom: 8px; }
.coverage-card span { font-size: 14px; color: var(--text-secondary); }

/* ===== Data Fields ===== */
.data-fields { padding: 80px 0; background: var(--bg); }
.fields-grid {
    display: grid; grid-template-columns: repeat(4, 1fr); gap: 24px;
}
.field-group {
    background: var(--white); border-radius: var(--radius); padding: 28px 24px;
    border: 1px solid var(--border);
}
.field-group h3 {
    font-size: 18px; margin-bottom: 16px; padding-bottom: 12px;
    border-bottom: 2px solid var(--primary-light); color: var(--primary);
}
.field-group ul { list-style: none; }
.field-group li {
    padding: 7px 0; font-size: 14px; color: var(--text-secondary);
    border-bottom: 1px dashed #f1f5f9;
}

/* ===== How It Works ===== */
.how-it-works { padding: 80px 0; background: var(--white); }
.steps {
    display: flex; align-items: center; justify-content: center; gap: 20px;
    flex-wrap: wrap;
}
.step {
    text-align: center; padding: 36px 28px; border-radius: var(--radius);
    background: var(--bg); border: 1px solid var(--border); min-width: 180px;
    transition: all .3s;
}
.step:hover { box-shadow: var(--shadow-lg); transform: translateY(-4px); }
.step-number {
    font-size: 14px; color: var(--primary); font-weight: 700;
    margin-bottom: 8px; letter-spacing: 2px;
}
.step-icon { font-size: 40px; margin-bottom: 12px; }
.step h3 { font-size: 20px; margin-bottom: 12px; }
.step p { font-size: 14px; color: var(--text-secondary); line-height: 1.8; }
.step-arrow {
    font-size: 28px; color: var(--primary); font-weight: 300; opacity: .5;
}

/* ===== Industry ===== */
.industry { padding: 80px 0; background: var(--bg); }
.industry-grid {
    display: grid; grid-template-columns: repeat(4, 1fr); gap: 24px;
}
.industry-card {
    text-align: center; padding: 32px 20px; border-radius: var(--radius);
    background: var(--white); border: 1px solid var(--border); transition: all .3s;
}
.industry-card:hover { box-shadow: var(--shadow); transform: translateY(-3px); }
.industry-icon { font-size: 42px; margin-bottom: 14px; }
.industry-card h3 { font-size: 18px; margin-bottom: 10px; }
.industry-card p { font-size: 13px; color: var(--text-secondary); line-height: 1.7; }

/* ===== Comparison ===== */
.comparison { padding: 80px 0; background: var(--white); }
.compare-table-wrap { overflow-x: auto; }
.compare-table {
    width: 100%; border-collapse: collapse; font-size: 15px;
}
.compare-table th {
    background: var(--primary); color: var(--white); padding: 14px 20px;
    text-align: left; font-weight: 600;
}
.compare-table th:first-child { border-radius: 8px 0 0 0; }
.compare-table th:last-child { border-radius: 0 8px 0 0; }
.compare-table .highlight-col { background: var(--accent); }
.compare-table td {
    padding: 14px 20px; border-bottom: 1px solid var(--border);
}
.compare-table tr:nth-child(even) td { background: #f8fafc; }
.compare-table td.highlight-col {
    font-weight: 600; color: var(--accent);
}

/* ===== FAQ ===== */
.faq { padding: 80px 0; background: var(--bg); }
.faq-list { max-width: 800px; margin: 0 auto; }
.faq-item {
    background: var(--white); border-radius: var(--radius);
    margin-bottom: 12px; border: 1px solid var(--border);
    overflow: hidden; transition: all .2s;
}
.faq-item:hover { border-color: var(--primary); }
.faq-item summary {
    padding: 18px 24px; font-size: 17px; font-weight: 600; cursor: pointer;
    list-style: none; display: flex; justify-content: space-between; align-items: center;
}
.faq-item summary::-webkit-details-marker { display: none; }
.faq-item summary::after {
    content: "+"; font-size: 22px; color: var(--primary);
    transition: transform .2s; font-weight: 300;
}
.faq-item[open] summary::after { content: "−"; }
.faq-answer { padding: 0 24px 20px; }
.faq-answer p { font-size: 15px; color: var(--text-secondary); line-height: 1.8; }

/* ===== About ===== */
.about { padding: 80px 0; background: var(--white); }
.about-content {
    display: grid; grid-template-columns: 1.5fr 1fr; gap: 40px; align-items: start;
}
.about-text p {
    font-size: 16px; color: var(--text-secondary); line-height: 1.9; margin-bottom: 16px;
}
.about-text strong { color: var(--text); }
.about-highlights {
    display: grid; grid-template-columns: repeat(3, 1fr); gap: 16px; margin-top: 28px;
}
.about-hl {
    padding: 20px; border-radius: var(--radius); background: var(--primary-light);
    text-align: center;
}
.about-hl h4 { font-size: 16px; color: var(--primary); margin-bottom: 8px; }
.about-hl p { font-size: 13px; color: var(--text-secondary); line-height: 1.6; }

.contact-card {
    background: linear-gradient(135deg, var(--primary), var(--primary-dark));
    color: var(--white); border-radius: var(--radius); padding: 36px 28px;
}
.contact-card h3 { font-size: 22px; margin-bottom: 20px; }
.contact-card ul { list-style: none; }
.contact-card li { padding: 10px 0; font-size: 15px; border-bottom: 1px solid rgba(255,255,255,.15); }
.contact-card li strong { display: inline-block; width: 80px; }

/* ===== Footer ===== */
.footer {
    background: #0f172a; color: #94a3b8; padding: 50px 0 24px;
}
.footer-grid { display: grid; grid-template-columns: 1.5fr 1fr 1fr 1fr; gap: 40px; margin-bottom: 40px; }
.footer-brand h3 { font-size: 24px; color: var(--white); margin-bottom: 12px; }
.footer-brand p { font-size: 14px; line-height: 1.8; }
.footer-links h4 { color: var(--white); font-size: 16px; margin-bottom: 16px; }
.footer-links a { display: block; color: #94a3b8; font-size: 14px; padding: 4px 0; }
.footer-links a:hover { color: var(--white); }
.footer-bottom {
    border-top: 1px solid #1e293b; padding-top: 20px;
    text-align: center; font-size: 14px;
}
.footer-bottom a { color: #94a3b8; }
.footer-bottom a:hover { color: var(--white); }

/* ===== Sidebar Widget ===== */
.sidebar-widget { position: fixed; right: 0; top: 50%; transform: translateY(-50%); z-index: 200; display: flex; }
.sidebar-toggle {
    width: 36px; height: 100px; background: var(--primary); color: var(--white);
    border-radius: 8px 0 0 8px; display: flex; align-items: center; justify-content: center;
    cursor: pointer; font-size: 14px; font-weight: 700; transition: all .2s;
    writing-mode: vertical-rl; letter-spacing: 2px;
}
.sidebar-toggle:hover { background: var(--primary-dark); }

.sidebar-panel {
    display: none; width: 260px; background: var(--white);
    border-radius: 12px 0 0 12px; padding: 28px 24px;
    box-shadow: -4px 0 20px rgba(0,0,0,.15); position: relative;
}
.sidebar-panel.open { display: block; }
.sidebar-close {
    position: absolute; top: 8px; right: 12px; font-size: 24px; cursor: pointer;
    color: #94a3b8; line-height: 1;
}
.sidebar-close:hover { color: var(--text); }
.sidebar-panel h3 { font-size: 22px; color: var(--primary); margin-bottom: 4px; }
.sidebar-panel > p { font-size: 13px; color: var(--text-secondary); margin-bottom: 16px; }
.sidebar-features { margin-bottom: 20px; }
.sidebar-features span { display: block; font-size: 13px; padding: 4px 0; color: var(--text-secondary); }
.sidebar-panel .btn { margin-bottom: 10px; }
.sidebar-tip { text-align: center; font-size: 12px; color: #f97316; margin-top: 8px; }

/* ===== Responsive ===== */
@media (max-width: 1024px) {
    .hero-inner { grid-template-columns: 1fr; }
    .hero-image { max-width: 500px; margin: 0 auto; }
    .pain-grid { grid-template-columns: repeat(2, 1fr); }
    .features-grid { grid-template-columns: repeat(2, 1fr); }
    .fields-grid { grid-template-columns: repeat(2, 1fr); }
    .industry-grid { grid-template-columns: repeat(2, 1fr); }
    .about-content { grid-template-columns: 1fr; }
    .footer-grid { grid-template-columns: repeat(2, 1fr); }
    .nav { display: none; }
}

@media (max-width: 640px) {
    .hero-title { font-size: 28px; }
    .section-title { font-size: 24px; }
    .pain-grid { grid-template-columns: 1fr; }
    .features-grid { grid-template-columns: 1fr; }
    .coverage-grid { grid-template-columns: repeat(2, 1fr); }
    .fields-grid { grid-template-columns: 1fr; }
    .industry-grid { grid-template-columns: 1fr; }
    .about-highlights { grid-template-columns: 1fr; }
    .footer-grid { grid-template-columns: 1fr; }
    .steps { flex-direction: column; }
    .step-arrow { transform: rotate(90deg); }
    .hero-stats { gap: 16px; }
    .hero-cta { flex-direction: column; }
    .header-actions .btn { padding: 8px 16px; font-size: 13px; }
    .sidebar-widget { display: none; }
}