:root {
  --primary: #0284c7;
  --primary-dark: #0369a1;
  --primary-light: #e0f2fe;
  --accent: #06b6d4;
  --accent-glow: rgba(6, 182, 212, 0.15);
  --bg-main: #f8fafc;
  --bg-card: #ffffff;
  --text-main: #0f172a;
  --text-muted: #475569;
  --border-color: #cbd5e1;
  --shadow-sm: 0 2px 4px rgba(0,0,0,0.04);
  --shadow-md: 0 6px 16px rgba(2,132,199,0.08);
  --shadow-lg: 0 12px 32px rgba(2,132,199,0.12);
  --radius: 12px;
  --transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
}

* { box-sizing: border-box; margin: 0; padding: 0; }
html { scroll-behavior: smooth; font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif; background-color: var(--bg-main); color: var(--text-main); line-height: 1.6; }
body { overflow-x: hidden; }

.container { width: 100%; max-width: 1200px; margin: 0 auto; padding: 0 20px; }

/* Header */
.site-header { position: sticky; top: 0; z-index: 1000; background: rgba(255, 255, 255, 0.95); backdrop-filter: blur(10px); border-bottom: 1px solid rgba(226, 232, 240, 0.8); }
.header-inner { display: flex; align-items: center; justify-content: space-between; height: 72px; }
.brand-zone { display: flex; align-items: center; gap: 12px; }
.ai-page-logo { height: 38px; width: auto; display: block; }
.nav-links { display: flex; align-items: center; gap: 0; list-style: none; }
.nav-links li a { display: inline-block; padding: 8px 12px; color: var(--text-main); text-decoration: none; font-size: 14px; font-weight: 500; transition: var(--transition); border-radius: 6px; }
.nav-links li a:hover { color: var(--primary); background: var(--primary-light); }
.header-actions { display: flex; align-items: center; gap: 12px; }
.btn-primary { background: linear-gradient(135deg, var(--primary), var(--accent)); color: #fff; text-decoration: none; padding: 10px 22px; border-radius: 8px; font-weight: 600; font-size: 14px; border: none; cursor: pointer; display: inline-flex; align-items: center; justify-content: center; transition: var(--transition); box-shadow: 0 4px 12px rgba(2, 132, 199, 0.25); }
.btn-primary:hover { opacity: 0.95; transform: translateY(-1px); box-shadow: 0 6px 16px rgba(2, 132, 199, 0.35); }
.btn-outline { background: transparent; color: var(--primary); border: 1.5px solid var(--primary); padding: 9px 20px; border-radius: 8px; font-weight: 600; font-size: 14px; text-decoration: none; display: inline-flex; align-items: center; justify-content: center; transition: var(--transition); }
.btn-outline:hover { background: var(--primary-light); }

/* Mobile Menu Toggle */
.menu-toggle { display: none; background: none; border: none; font-size: 24px; color: var(--text-main); cursor: pointer; }

/* Hero Section (No Images!) */
.hero-section { padding: 90px 0 70px; background: linear-gradient(180deg, #e0f2fe 0%, #f8fafc 100%); text-align: center; position: relative; overflow: hidden; }
.hero-badge { display: inline-flex; align-items: center; gap: 8px; background: rgba(2, 132, 199, 0.1); border: 1px solid rgba(2, 132, 199, 0.2); color: var(--primary-dark); padding: 6px 16px; border-radius: 50px; font-size: 13px; font-weight: 600; margin-bottom: 24px; }
.hero-title { font-size: 36px; font-weight: 800; color: var(--text-main); line-height: 1.25; margin-bottom: 20px; letter-spacing: -0.5px; }
.hero-subtitle { font-size: 18px; color: var(--text-muted); max-width: 800px; margin: 0 auto 32px; font-weight: 400; }
.hero-ctas { display: flex; justify-content: center; gap: 16px; flex-wrap: wrap; margin-bottom: 48px; }
.hero-ctas .btn-primary { padding: 14px 32px; font-size: 16px; }
.hero-metrics { display: grid; grid-template-columns: repeat(auto-fit, minmax(220px, 1fr)); gap: 20px; max-width: 1000px; margin: 0 auto; }
.metric-card { background: var(--bg-card); padding: 24px; border-radius: var(--radius); border: 1px solid rgba(203, 213, 225, 0.6); box-shadow: var(--shadow-sm); transition: var(--transition); }
.metric-card:hover { transform: translateY(-3px); box-shadow: var(--shadow-md); border-color: var(--primary); }
.metric-value { font-size: 32px; font-weight: 800; color: var(--primary); line-height: 1; margin-bottom: 8px; }
.metric-label { font-size: 14px; color: var(--text-muted); font-weight: 500; }

/* Section Standard Styles */
.section { padding: 80px 0; border-bottom: 1px solid #f1f5f9; }
.section-header { text-align: center; max-width: 760px; margin: 0 auto 48px; }
.section-tag { color: var(--primary); font-weight: 700; font-size: 13px; text-transform: uppercase; letter-spacing: 1px; margin-bottom: 8px; display: block; }
.section-title { font-size: 28px; font-weight: 700; color: var(--text-main); margin-bottom: 12px; }
.section-desc { font-size: 15px; color: var(--text-muted); }

/* Card Grids */
.grid-3 { display: grid; grid-template-columns: repeat(auto-fit, minmax(320px, 1fr)); gap: 24px; }
.grid-4 { display: grid; grid-template-columns: repeat(auto-fit, minmax(250px, 1fr)); gap: 20px; }

.feature-card { background: var(--bg-card); border-radius: var(--radius); padding: 28px; border: 1px solid #e2e8f0; transition: var(--transition); box-shadow: var(--shadow-sm); display: flex; flex-direction: column; justify-content: space-between; }
.feature-card:hover { transform: translateY(-4px); box-shadow: var(--shadow-lg); border-color: var(--accent); }
.card-icon { width: 48px; height: 48px; border-radius: 10px; background: var(--primary-light); color: var(--primary); display: flex; align-items: center; justify-content: center; font-weight: 700; font-size: 20px; margin-bottom: 20px; }
.card-title { font-size: 18px; font-weight: 700; margin-bottom: 10px; color: var(--text-main); }
.card-desc { font-size: 14px; color: var(--text-muted); margin-bottom: 16px; line-height: 1.6; }
.card-tags { display: flex; flex-wrap: wrap; gap: 6px; }
.card-tag { font-size: 12px; padding: 3px 8px; background: #f1f5f9; border-radius: 4px; color: var(--text-muted); }

/* Image Showcase */
.case-card { background: var(--bg-card); border-radius: var(--radius); overflow: hidden; border: 1px solid #e2e8f0; transition: var(--transition); box-shadow: var(--shadow-sm); }
.case-card:hover { box-shadow: var(--shadow-md); transform: translateY(-3px); }
.case-img-wrap { width: 100%; aspect-ratio: 16/9; overflow: hidden; background: #f1f5f9; }
.case-img-wrap img { width: 100%; height: 100%; object-fit: cover; display: block; transition: transform 0.5s ease; }
.case-card:hover .case-img-wrap img { transform: scale(1.05); }
.case-body { padding: 20px; }

/* Comparison Section */
.comparison-box { background: var(--bg-card); border-radius: var(--radius); padding: 32px; border: 1px solid #e2e8f0; box-shadow: var(--shadow-md); }
.rating-banner { display: flex; align-items: center; justify-content: space-between; background: linear-gradient(135deg, #e0f2fe, #ecfeff); padding: 20px 28px; border-radius: 10px; margin-bottom: 32px; border: 1px solid #bae6fd; flex-wrap: wrap; gap: 16px; }
.rating-info { display: flex; align-items: center; gap: 16px; }
.rating-stars { color: #f59e0b; font-size: 24px; }
.rating-score { font-size: 32px; font-weight: 800; color: var(--primary-dark); }
.comp-table-wrap { overflow-x: auto; }
.comp-table { width: 100%; border-collapse: collapse; text-align: left; font-size: 14px; }
.comp-table th, .comp-table td { padding: 16px; border-bottom: 1px solid #e2e8f0; }
.comp-table th { background: #f8fafc; font-weight: 700; color: var(--text-main); }
.comp-table tr:hover { background: #f0fdfa; }
.highlight-cell { font-weight: 700; color: var(--primary); background: rgba(224, 242, 254, 0.4); }

/* Interactive Need Matching */
.matching-card { background: linear-gradient(135deg, #ffffff, #f0f9ff); border: 1px solid #bae6fd; border-radius: var(--radius); padding: 32px; text-align: center; }
.matching-options { display: flex; justify-content: center; gap: 12px; flex-wrap: wrap; margin: 24px 0; }
.opt-btn { padding: 10px 20px; border: 1px solid var(--border-color); background: #fff; border-radius: 30px; cursor: pointer; font-weight: 500; font-size: 14px; transition: var(--transition); }
.opt-btn.active, .opt-btn:hover { background: var(--primary); color: #fff; border-color: var(--primary); }

/* FAQ Accordion */
.faq-grid { max-width: 900px; margin: 0 auto; display: flex; flex-direction: column; gap: 14px; }
.faq-item { background: var(--bg-card); border: 1px solid #e2e8f0; border-radius: 8px; overflow: hidden; transition: var(--transition); }
.faq-question { padding: 18px 24px; font-weight: 600; cursor: pointer; display: flex; justify-content: space-between; align-items: center; font-size: 16px; color: var(--text-main); background: #fff; }
.faq-question::after { content: "+"; font-size: 20px; font-weight: 400; color: var(--primary); transition: transform 0.3s ease; }
.faq-item.active .faq-question::after { content: "−"; transform: rotate(180deg); }
.faq-answer { padding: 0 24px 18px; color: var(--text-muted); font-size: 14px; display: none; line-height: 1.6; border-top: 1px solid #f1f5f9; padding-top: 14px; }
.faq-item.active .faq-answer { display: block; }

/* User Reviews Grid */
.reviews-grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(300px, 1fr)); gap: 20px; }
.review-card { background: var(--bg-card); padding: 24px; border-radius: var(--radius); border: 1px solid #e2e8f0; box-shadow: var(--shadow-sm); }
.reviewer-info { display: flex; align-items: center; gap: 12px; margin-bottom: 12px; }
.reviewer-avatar { width: 44px; height: 44px; border-radius: 50%; background: var(--primary-light); color: var(--primary); font-weight: 700; display: flex; align-items: center; justify-content: center; }
.reviewer-name { font-weight: 700; font-size: 15px; }
.reviewer-role { font-size: 12px; color: var(--text-muted); }

/* Form Section */
.contact-wrap { display: grid; grid-template-columns: 1fr 1fr; gap: 40px; background: var(--bg-card); border-radius: var(--radius); border: 1px solid #e2e8f0; padding: 40px; box-shadow: var(--shadow-md); }
.form-group { margin-bottom: 18px; }
.form-group label { display: block; font-size: 14px; font-weight: 600; margin-bottom: 6px; color: var(--text-main); }
.form-control { width: 100%; padding: 12px 16px; border: 1px solid var(--border-color); border-radius: 8px; font-size: 14px; outline: none; transition: var(--transition); background: #f8fafc; }
.form-control:focus { border-color: var(--primary); background: #fff; box-shadow: 0 0 0 3px rgba(2, 132, 199, 0.15); }
textarea.form-control { resize: vertical; min-height: 110px; }

/* Article & Friend Links List */
.links-box { background: #f8fafc; border-radius: var(--radius); padding: 24px; border: 1px solid #e2e8f0; }
.link-list { display: flex; flex-wrap: wrap; gap: 12px; list-style: none; margin-top: 12px; }
.link-list a { display: inline-block; padding: 6px 14px; background: #fff; border: 1px solid #cbd5e1; border-radius: 6px; color: var(--text-muted); text-decoration: none; font-size: 13px; transition: var(--transition); }
.link-list a:hover { border-color: var(--primary); color: var(--primary); background: var(--primary-light); }

/* Footer */
.site-footer { background: #0f172a; color: #94a3b8; padding: 60px 0 30px; font-size: 14px; }
.footer-grid { display: grid; grid-template-columns: 2fr 1fr 1fr 1.5fr; gap: 40px; margin-bottom: 40px; }
.footer-brand h3 { color: #fff; font-size: 20px; margin-bottom: 12px; }
.footer-col h4 { color: #f8fafc; font-size: 15px; margin-bottom: 16px; font-weight: 600; }
.footer-col ul { list-style: none; }
.footer-col ul li { margin-bottom: 10px; }
.footer-col ul li a { color: #94a3b8; text-decoration: none; transition: var(--transition); }
.footer-col ul li a:hover { color: #38bdf8; }
.footer-qr { width: 110px; border-radius: 6px; margin-top: 8px; }
.footer-bottom { border-top: 1px solid #1e293b; padding-top: 24px; text-align: center; color: #64748b; font-size: 13px; }

/* Floating Support */
.float-support { position: fixed; right: 24px; bottom: 24px; z-index: 999; display: flex; flex-direction: column; gap: 10px; }
.float-btn { width: 50px; height: 50px; border-radius: 50%; background: var(--primary); color: #fff; display: flex; align-items: center; justify-content: center; box-shadow: var(--shadow-lg); text-decoration: none; font-size: 20px; transition: var(--transition); cursor: pointer; border: none; }
.float-btn:hover { transform: scale(1.1); background: var(--primary-dark); }

/* Responsive adjustments */
@media (max-width: 992px) {
  .hero-title { font-size: 28px; }
  .contact-wrap { grid-template-columns: 1fr; }
  .footer-grid { grid-template-columns: 1fr 1fr; }
}
@media (max-width: 768px) {
  .menu-toggle { display: block; }
  .nav-links { display: none; width: 100%; position: absolute; top: 72px; left: 0; background: #fff; flex-direction: column; padding: 16px 0; border-bottom: 1px solid #e2e8f0; box-shadow: var(--shadow-md); }
  .nav-links.active { display: flex; }
  .header-actions { display: none; }
  .footer-grid { grid-template-columns: 1fr; }
  .hero-section { padding: 60px 0 40px; }
  .rating-banner { flex-direction: column; align-items: flex-start; }
}