/*
  ════════════════════════════════════════════════════════════
  RICHING TRADING 瑞成贸易 - 全球化外贸官网样式表
  修改入口：
  - 颜色主题：修改 :root 中的 CSS 变量
  - 字体/间距：搜索对应 class 名修改
  ════════════════════════════════════════════════════════════
*/

/* ========== CSS Variables ========== */
:root {
  --primary: #0ea5e9;
  --primary-dark: #0284c7;
  --secondary: #1e40af;
  --accent-red: #dc2626;
  --dark: #0a192f;
  --dark-light: #112240;
  --text: #334155;
  --text-light: #64748b;
  --bg: #f8fafc;
  --white: #ffffff;
  --radius: 14px;
  --shadow: 0 10px 40px rgba(0,0,0,0.08);
}

/* ========== Reset & Base ========== */
*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }
html { scroll-behavior: smooth; font-size: 16px; }
body {
  font-family: 'Segoe UI', 'PingFang SC', 'Microsoft YaHei', 'Helvetica Neue', Arial, sans-serif;
  color: var(--text); background: var(--bg); line-height: 1.7; overflow-x: hidden;
}
body[dir="rtl"] { direction: rtl; }
a { text-decoration: none; color: inherit; }
img, video { max-width: 100%; display: block; }
.container { max-width: 1200px; margin: 0 auto; padding: 0 24px; }

/* ========== Navbar ========== */
.navbar {
  position: fixed; top: 0; left: 0; right: 0; z-index: 1000;
  background: rgba(255, 255, 255, 0.98);
  backdrop-filter: blur(10px);
  box-shadow: 0 2px 20px rgba(0,0,0,0.06);
  transition: all 0.3s;
}
.navbar .container { display: flex; align-items: center; justify-content: space-between; height: 80px; }
.navbar .logo { display: flex; align-items: center; }
.navbar .logo img { height: 52px; width: auto; border-radius: 6px; }
.nav-links { display: flex; gap: 28px; list-style: none; }
.nav-links a { color: var(--text); font-size: 0.88rem; font-weight: 600; transition: color 0.3s; position: relative; }
.nav-links a:hover, .nav-links a.active { color: var(--primary); }
.nav-links a::after { content: ''; position: absolute; bottom: -4px; left: 0; width: 0; height: 2px; background: var(--primary); transition: width 0.3s; }
body[dir="rtl"] .nav-links a::after { left: auto; right: 0; }
.nav-links a:hover::after, .nav-links a.active::after { width: 100%; }

/* Language Switcher */
.lang-switcher { position: relative; }
.lang-btn { display: flex; align-items: center; gap: 8px; padding: 8px 14px; border: 1px solid #cbd5e1; border-radius: 25px; background: #fff; color: var(--text); font-size: 0.82rem; font-weight: 600; cursor: pointer; transition: all 0.3s; }
.lang-btn:hover { border-color: var(--primary); color: var(--primary); }
.lang-btn .flag { font-size: 1.1rem; }
.lang-dropdown { position: absolute; top: 110%; right: 0; min-width: 180px; background: #fff; border-radius: 12px; box-shadow: var(--shadow); padding: 8px 0; opacity: 0; visibility: hidden; transform: translateY(-10px); transition: all 0.25s; z-index: 1001; max-height: 320px; overflow-y: auto; }
body[dir="rtl"] .lang-dropdown { right: auto; left: 0; }
.lang-dropdown.open { opacity: 1; visibility: visible; transform: translateY(0); }
.lang-option { display: flex; align-items: center; gap: 10px; padding: 10px 18px; cursor: pointer; transition: background 0.2s; font-size: 0.85rem; }
.lang-option:hover { background: #f1f5f9; }
.lang-option.active { background: rgba(14,165,233,0.08); color: var(--primary); font-weight: 600; }
.lang-option .flag { font-size: 1.1rem; }

/* Mobile Toggle */
.mobile-toggle { display: none; flex-direction: column; gap: 5px; cursor: pointer; z-index: 1001; }
.mobile-toggle span { width: 26px; height: 2.5px; background: var(--text); border-radius: 2px; transition: all 0.3s; }

/* ========== Hero ========== */
.hero { min-height: 100vh; display: flex; align-items: center; background: linear-gradient(135deg, var(--dark) 0%, var(--dark-light) 50%, #0f2a52 100%); position: relative; overflow: hidden; }
.hero::before { content: ''; position: absolute; top: -50%; right: -20%; width: 700px; height: 700px; background: radial-gradient(circle, rgba(14,165,233,0.1) 0%, transparent 70%); border-radius: 50%; }
.hero::after { content: ''; position: absolute; bottom: -30%; left: -10%; width: 500px; height: 500px; background: radial-gradient(circle, rgba(30,64,175,0.08) 0%, transparent 70%); border-radius: 50%; }
.hero .grid-bg { position: absolute; inset: 0; opacity: 0.03; background-image: linear-gradient(rgba(255,255,255,0.1) 1px, transparent 1px), linear-gradient(90deg, rgba(255,255,255,0.1) 1px, transparent 1px); background-size: 60px 60px; }
.hero-content { position: relative; z-index: 2; max-width: 820px; padding-top: 110px; }
.hero-badge { display: inline-block; padding: 6px 18px; background: rgba(14,165,233,0.15); color: var(--primary); border-radius: 25px; font-size: 0.85rem; font-weight: 600; border: 1px solid rgba(14,165,233,0.3); margin-bottom: 24px; }
.hero h1 { font-size: 3.2rem; font-weight: 800; color: #fff; line-height: 1.2; margin-bottom: 20px; }
.hero h1 .accent { color: var(--primary); }
.hero h1 .accent-red { color: #f87171; }
.hero-subtitle { font-size: 1.15rem; color: #94a3b8; margin-bottom: 40px; max-width: 620px; }
.hero-cta { display: flex; gap: 16px; flex-wrap: wrap; }
.btn { padding: 14px 32px; border-radius: 10px; font-size: 0.95rem; font-weight: 600; cursor: pointer; transition: all 0.3s; border: none; display: inline-flex; align-items: center; gap: 8px; }
.btn-primary { background: var(--primary); color: #fff; }
.btn-primary:hover { background: var(--primary-dark); transform: translateY(-2px); box-shadow: 0 8px 25px rgba(14,165,233,0.35); }
.btn-outline { background: transparent; color: #e2e8f0; border: 1.5px solid rgba(226,232,240,0.3); }
.btn-outline:hover { border-color: var(--primary); color: var(--primary); transform: translateY(-2px); }
.hero-stats { display: flex; gap: 48px; margin-top: 60px; padding-top: 32px; border-top: 1px solid rgba(255,255,255,0.08); }
.stat-item h3 { font-size: 2rem; color: var(--primary); font-weight: 700; }
.stat-item p { font-size: 0.85rem; color: #94a3b8; margin-top: 4px; }

/* ========== Sections ========== */
.section { padding: 100px 0; }
.section-dark { background: var(--dark); color: #fff; }
.section-header { text-align: center; margin-bottom: 64px; }
.section-tag { display: inline-block; padding: 4px 16px; background: rgba(14,165,233,0.1); color: var(--primary); border-radius: 20px; font-size: 0.8rem; font-weight: 600; border: 1px solid rgba(14,165,233,0.2); margin-bottom: 16px; }
.section-header h2 { font-size: 2.2rem; font-weight: 700; margin-bottom: 12px; }
.section-header p { font-size: 1.05rem; color: var(--text-light); max-width: 650px; margin: 0 auto; }
.section-dark .section-header p { color: #94a3b8; }

/* ========== About ========== */
.about-grid { display: grid; grid-template-columns: 1fr 1fr; gap: 60px; align-items: center; }
.about-text h3 { font-size: 1.6rem; margin-bottom: 20px; color: #1e293b; }
.about-text p { color: var(--text-light); margin-bottom: 16px; font-size: 0.98rem; }
.about-highlights { display: grid; grid-template-columns: 1fr 1fr; gap: 20px; margin-top: 32px; }
.highlight-card { padding: 20px; background: #f1f5f9; border-radius: 12px; border-left: 3px solid var(--primary); }
body[dir="rtl"] .highlight-card { border-left: none; border-right: 3px solid var(--primary); }
.highlight-card .num { font-size: 1.8rem; font-weight: 700; color: var(--primary); }
.highlight-card .label { font-size: 0.85rem; color: var(--text-light); margin-top: 4px; }
.about-image { position: relative; border-radius: 16px; overflow: hidden; background: linear-gradient(135deg, var(--dark), #1e3a5f); min-height: 420px; display: flex; align-items: center; justify-content: center; }
.about-image .globe { font-size: 8rem; opacity: 0.12; position: absolute; }
.company-card { background: rgba(255,255,255,0.96); border-radius: 16px; padding: 36px; position: relative; z-index: 2; text-align: center; box-shadow: 0 20px 50px rgba(0,0,0,0.3); }
.company-card img { max-width: 240px; margin: 0 auto 16px; border-radius: 8px; }
.company-card .en { font-size: 0.78rem; color: var(--text-light); margin-bottom: 16px; }
.company-card .badges { display: flex; gap: 8px; justify-content: center; flex-wrap: wrap; }
.company-card .badge-item { padding: 4px 12px; background: var(--primary); color: #fff; border-radius: 12px; font-size: 0.72rem; font-weight: 600; }

/* ========== OUTPUT 产出品牌专区 ========== */
.output-section { background: linear-gradient(135deg, #f0f9ff 0%, #f5f3ff 50%, #f0fdfa 100%); position: relative; overflow: hidden; }
.output-section::before { content: ''; position: absolute; top: -20%; right: -10%; width: 500px; height: 500px; background: radial-gradient(circle, rgba(14,165,233,0.08) 0%, transparent 70%); border-radius: 50%; }
.output-section::after { content: ''; position: absolute; bottom: -20%; left: -10%; width: 400px; height: 400px; background: radial-gradient(circle, rgba(13,148,136,0.06) 0%, transparent 70%); border-radius: 50%; }
.output-grid { display: grid; grid-template-columns: 1fr 1.2fr; gap: 60px; align-items: center; position: relative; z-index: 2; }

/* 手机 mockup */
.output-phone { display: flex; justify-content: center; }
.phone-frame { width: 280px; height: 560px; background: #1e293b; border-radius: 42px; padding: 14px; box-shadow: 0 30px 70px rgba(0,0,0,0.18), inset 0 0 0 2px rgba(255,255,255,0.08); position: relative; }
.phone-frame::before { content: ''; position: absolute; top: 18px; left: 50%; transform: translateX(-50%); width: 90px; height: 22px; background: #0f172a; border-radius: 12px; z-index: 3; }
.phone-screen { width: 100%; height: 100%; background: linear-gradient(180deg, #0ea5e9 0%, #0d9488 100%); border-radius: 30px; display: flex; flex-direction: column; align-items: center; justify-content: center; padding: 32px; text-align: center; color: #fff; }
.phone-screen .app-icon { width: 120px; height: 120px; border-radius: 28px; margin-bottom: 20px; box-shadow: 0 12px 30px rgba(0,0,0,0.2); }
.phone-screen h4 { font-size: 1.6rem; font-weight: 800; margin-bottom: 8px; letter-spacing: 1px; }
.phone-screen p { font-size: 0.9rem; opacity: 0.95; line-height: 1.5; }
.app-dots { display: flex; gap: 8px; margin-top: 32px; }
.app-dots span { width: 8px; height: 8px; border-radius: 50%; background: rgba(255,255,255,0.5); }
.app-dots span:nth-child(2) { background: #fff; }

/* 右侧内容 */
.output-content p { font-size: 1.05rem; color: var(--text-light); margin-bottom: 28px; line-height: 1.7; }
.output-features { display: flex; flex-direction: column; gap: 18px; margin-bottom: 32px; }
.output-feature { display: flex; gap: 16px; padding: 18px 20px; background: #fff; border-radius: 14px; border: 1px solid #e2e8f0; box-shadow: 0 4px 16px rgba(0,0,0,0.03); transition: all 0.3s; }
.output-feature:hover { transform: translateY(-3px); box-shadow: 0 8px 24px rgba(14,165,233,0.1); border-color: rgba(14,165,233,0.2); }
.output-feature .of-icon { width: 46px; height: 46px; border-radius: 12px; background: rgba(14,165,233,0.1); display: flex; align-items: center; justify-content: center; font-size: 1.4rem; flex-shrink: 0; }
.output-feature h4 { font-size: 1rem; color: #1e293b; margin-bottom: 4px; }
.output-feature p { font-size: 0.85rem; color: #64748b; margin: 0; line-height: 1.5; }
.output-cta { display: flex; gap: 16px; flex-wrap: wrap; }
.output-section .btn-primary { background: linear-gradient(135deg, var(--primary), #0d9488); }
.output-section .btn-outline { color: var(--primary); border-color: var(--primary); }
.output-section .btn-outline:hover { background: var(--primary); color: #fff; }

/* 社交媒体链接 */
.footer-social a[href^="https://www.xiaohongshu.com"] { color: #ff2442; }
.footer-social a[href^="https://www.xiaohongshu.com"]:hover { color: #ff4d6d; }

/* ========== Business Scope ========== */
.scope-grid { display: grid; grid-template-columns: repeat(auto-fill, minmax(360px, 1fr)); gap: 28px; }
.scope-card { background: #fff; border-radius: var(--radius); overflow: hidden; border: 1px solid #e2e8f0; transition: all 0.35s; position: relative; display: flex; flex-direction: column; }
.scope-card::before { content: ''; position: absolute; top: 0; left: 0; right: 0; height: 4px; transition: height 0.3s; }
.scope-card:hover { transform: translateY(-6px); box-shadow: var(--shadow); border-color: transparent; }
.scope-card:hover::before { height: 6px; }
.scope-card-inner { padding: 32px; flex: 1; display: grid; grid-template-rows: auto auto auto 1fr; }
.scope-card .card-icon { width: 56px; height: 56px; border-radius: 14px; display: flex; align-items: center; justify-content: center; font-size: 1.6rem; margin-bottom: 18px; }
.scope-card h4 { font-size: 1.15rem; margin-bottom: 12px; color: #1e293b; font-weight: 700; }
.scope-card .tags { display: flex; flex-wrap: wrap; gap: 6px; margin-bottom: 14px; }
.scope-card .tag { padding: 3px 12px; border-radius: 12px; font-size: 0.75rem; font-weight: 500; background: #f1f5f9; color: #475569; }
.scope-card .desc { font-size: 0.86rem; color: #94a3b8; line-height: 1.65; }

/* Category Colors */
.cat-energy::before { background: linear-gradient(90deg, #22c55e, #16a34a); }
.cat-energy .card-icon { background: rgba(34,197,94,0.1); color: #22c55e; }
.cat-chem::before { background: linear-gradient(90deg, #3b82f6, #2563eb); }
.cat-chem .card-icon { background: rgba(59,130,246,0.1); color: #3b82f6; }
.cat-electro::before { background: linear-gradient(90deg, #f59e0b, #d97706); }
.cat-electro .card-icon { background: rgba(245,158,11,0.1); color: #f59e0b; }
.cat-mach::before { background: linear-gradient(90deg, #8b5cf6, #7c3aed); }
.cat-mach .card-icon { background: rgba(139,92,246,0.1); color: #8b5cf6; }
.cat-build::before { background: linear-gradient(90deg, #ef4444, #dc2626); }
.cat-build .card-icon { background: rgba(239,68,68,0.1); color: #ef4444; }
.cat-outdoor::before { background: linear-gradient(90deg, #14b8a6, #0d9488); }
.cat-outdoor .card-icon { background: rgba(20,184,166,0.1); color: #14b8a6; }
.cat-service::before { background: linear-gradient(90deg, #6366f1, #4f46e5); }
.cat-service .card-icon { background: rgba(99,102,241,0.1); color: #6366f1; }

/* Category Video Section */
.category-video { background: #f8fafc; border-top: 1px solid #e2e8f0; padding: 20px 32px 28px; }
.category-video h5 { font-size: 0.9rem; color: #475569; margin-bottom: 12px; display: flex; align-items: center; gap: 8px; }
.category-video h5::before { content: ''; display: inline-block; width: 6px; height: 6px; border-radius: 50%; background: var(--accent-red); }
.video-wrapper { position: relative; border-radius: 12px; overflow: hidden; background: #000; }
.video-wrapper video { display: block; width: 100%; aspect-ratio: 16/9; object-fit: cover; background: #000; }
.video-hint { position: absolute; bottom: 0; left: 0; right: 0; padding: 10px 14px; background: rgba(0,0,0,0.65); color: #e2e8f0; font-size: 0.75rem; display: flex; align-items: center; gap: 8px; }
.video-hint .dot { width: 8px; height: 8px; border-radius: 50%; background: var(--accent-red); animation: pulse 1.5s infinite; }
@keyframes pulse { 0%,100% { opacity: 1; } 50% { opacity: 0.4; } }

/* ========== Advantages ========== */
.adv-grid { display: grid; grid-template-columns: repeat(4, 1fr); gap: 24px; }
.adv-card { background: rgba(255,255,255,0.03); border: 1px solid rgba(255,255,255,0.06); border-radius: var(--radius); padding: 36px 28px; text-align: center; transition: all 0.35s; }
.adv-card:hover { background: rgba(14,165,233,0.05); border-color: rgba(14,165,233,0.2); transform: translateY(-4px); }
.adv-card .adv-icon { width: 64px; height: 64px; border-radius: 50%; background: rgba(14,165,233,0.1); margin: 0 auto 20px; display: flex; align-items: center; justify-content: center; font-size: 1.8rem; }
.adv-card h4 { font-size: 1.05rem; color: #e2e8f0; margin-bottom: 10px; }
.adv-card p { font-size: 0.85rem; color: #94a3b8; line-height: 1.6; }

/* ========== Process ========== */
.process-flow { display: flex; justify-content: space-between; position: relative; margin-top: 48px; }
.process-flow::before { content: ''; position: absolute; top: 32px; left: 10%; right: 10%; height: 2px; background: linear-gradient(90deg, var(--primary), var(--secondary), var(--primary)); border-radius: 2px; }
.process-step { text-align: center; position: relative; z-index: 2; flex: 1; }
.process-step .step-num { width: 64px; height: 64px; border-radius: 50%; margin: 0 auto 16px; display: flex; align-items: center; justify-content: center; font-size: 1.4rem; font-weight: 700; color: #fff; background: linear-gradient(135deg, var(--primary), var(--primary-dark)); }
.process-step h5 { font-size: 0.95rem; margin-bottom: 6px; color: #1e293b; }
.section-dark .process-step h5 { color: #e2e8f0; }
.process-step p { font-size: 0.8rem; color: #94a3b8; }

/* ========== Cert Strip ========== */
.cert-strip { display: flex; justify-content: center; align-items: center; gap: 36px; padding: 40px 0; flex-wrap: wrap; }
.cert-item { display: flex; align-items: center; gap: 10px; color: var(--text-light); font-size: 0.88rem; font-weight: 500; }
.cert-item .cert-dot { width: 8px; height: 8px; border-radius: 50%; background: var(--primary); }

/* ========== Contact ========== */
.contact-grid { display: grid; grid-template-columns: 1fr 1fr; gap: 60px; }
.contact-info h3 { font-size: 1.6rem; margin-bottom: 24px; color: #1e293b; }
.contact-item { display: flex; align-items: flex-start; gap: 14px; margin-bottom: 20px; color: var(--text-light); font-size: 0.95rem; }
body[dir="rtl"] .contact-item { flex-direction: row-reverse; }
.contact-item .ci-icon { width: 42px; height: 42px; border-radius: 10px; flex-shrink: 0; display: flex; align-items: center; justify-content: center; background: rgba(14,165,233,0.1); color: var(--primary); font-size: 1.1rem; }
.contact-form { background: #fff; padding: 36px; border-radius: var(--radius); border: 1px solid #e2e8f0; box-shadow: 0 4px 20px rgba(0,0,0,0.04); }
.contact-form h4 { font-size: 1.2rem; margin-bottom: 24px; color: #1e293b; }
.form-group { margin-bottom: 18px; }
.form-group label { display: block; font-size: 0.85rem; font-weight: 600; margin-bottom: 6px; color: #475569; }
.form-group input, .form-group textarea, .form-group select { width: 100%; padding: 12px 16px; border: 1.5px solid #e2e8f0; border-radius: 10px; font-size: 0.9rem; font-family: inherit; transition: all 0.3s; background: #f8fafc; color: #1e293b; outline: none; }
.form-group input:focus, .form-group textarea:focus, .form-group select:focus { border-color: var(--primary); box-shadow: 0 0 0 3px rgba(14,165,233,0.1); }
.form-group textarea { resize: vertical; min-height: 100px; }
.btn-submit { width: 100%; padding: 14px; background: var(--primary); color: #fff; border: none; border-radius: 10px; font-size: 1rem; font-weight: 600; cursor: pointer; transition: all 0.3s; }
.btn-submit:hover { background: var(--primary-dark); transform: translateY(-2px); }

/* Honeypot 反垃圾字段：对正常用户不可见 */
.hp-field { position: absolute; left: -9999px; opacity: 0; pointer-events: none; height: 0; width: 0; border: 0; padding: 0; margin: 0; overflow: hidden; }

/* ========== Footer ========== */
.footer { background: var(--dark); color: #8892b0; padding: 56px 0 24px; border-top: 1px solid rgba(255,255,255,0.05); }
.footer-grid { display: grid; grid-template-columns: 2fr 1fr 1fr 1fr 1fr; gap: 32px; margin-bottom: 40px; }
.footer-brand h4 { font-size: 1.15rem; color: #fff; margin-bottom: 12px; }
.footer-brand img { height: 44px; margin-bottom: 14px; border-radius: 6px; }
.footer-brand p { font-size: 0.85rem; line-height: 1.7; }
.footer-col h5 { font-size: 0.9rem; color: #e2e8f0; margin-bottom: 16px; }
.footer-col ul { list-style: none; }
.footer-col li { margin-bottom: 10px; }
.footer-col a { font-size: 0.85rem; color: #8892b0; transition: color 0.3s; }
.footer-col a:hover { color: var(--primary); }
.footer-bottom { padding-top: 24px; border-top: 1px solid rgba(255,255,255,0.06); display: flex; justify-content: space-between; align-items: center; flex-wrap: wrap; gap: 12px; font-size: 0.8rem; }
.footer-bottom a { color: var(--primary); }

/* ========== Admin Edit Hint Bar ========== */
.edit-hint-bar { position: fixed; bottom: 20px; right: 20px; z-index: 999; background: #1e293b; color: #fff; padding: 12px 18px; border-radius: 10px; font-size: 0.8rem; box-shadow: 0 6px 24px rgba(0,0,0,0.2); max-width: 320px; line-height: 1.5; }
body[dir="rtl"] .edit-hint-bar { right: auto; left: 20px; }
.edit-hint-bar a { color: var(--primary); text-decoration: underline; }
.edit-hint-bar .close { float: right; margin-left: 10px; cursor: pointer; color: #94a3b8; }

/* ========== Animations ========== */
.fade-up { opacity: 0; transform: translateY(30px); transition: all 0.6s ease-out; }
.fade-up.visible { opacity: 1; transform: translateY(0); }

/* ========== Responsive ========== */
/* 平板及以下 */
@media (max-width: 992px) {
  .about-grid, .contact-grid, .output-grid { grid-template-columns: 1fr; gap: 40px; }
  .adv-grid { grid-template-columns: repeat(2, 1fr); }
  .scope-grid { grid-template-columns: 1fr; }
  .footer-grid { grid-template-columns: 1fr 1fr; }
  .hero h1 { font-size: 2.4rem; }
  .process-flow { flex-direction: column; gap: 24px; }
  .process-flow::before { display: none; }
  .output-content { order: 1; }
  .output-phone { order: 2; }
  .phone-frame { width: 240px; height: 480px; }
}

/* 手机端 */
@media (max-width: 640px) {
  .container { padding: 0 16px; }
  .navbar .container { height: 62px; }
  .navbar .logo img { height: 40px; }

  /* 移动端导航菜单（汉堡展开） */
  .nav-links {
    display: none;
    position: fixed; top: 62px; left: 0; right: 0;
    flex-direction: column;
    background: #fff;
    padding: 8px 24px 20px;
    gap: 0;
    box-shadow: 0 12px 30px rgba(0,0,0,0.12);
  }
  .nav-links.mobile-open { display: flex; }
  .nav-links li { width: 100%; }
  .nav-links a { display: block; padding: 14px 4px; font-size: 1rem; border-bottom: 1px solid #f1f5f9; }
  .nav-links a::after { display: none; }
  .mobile-toggle { display: flex; }

  /* 语言切换器 */
  .lang-btn { padding: 6px 10px; font-size: 0.72rem; gap: 5px; }
  .lang-btn .flag { font-size: 0.95rem; }
  .lang-dropdown { min-width: 150px; max-height: 46vh; }

  /* Hero */
  .hero { min-height: 92vh; }
  .hero-content { padding-top: 100px; }
  .hero h1 { font-size: 1.7rem; }
  .hero-subtitle { font-size: 0.95rem; margin-bottom: 28px; }
  .hero-cta { flex-direction: column; gap: 12px; }
  .btn { width: 100%; justify-content: center; padding: 13px 24px; font-size: 0.9rem; }
  .hero-stats { flex-wrap: wrap; gap: 18px; margin-top: 40px; padding-top: 24px; }
  .stat-item h3 { font-size: 1.5rem; }
  .stat-item p { font-size: 0.78rem; }

  /* 区块 */
  .section { padding: 56px 0; }
  .section-header { margin-bottom: 36px; }
  .section-header h2 { font-size: 1.5rem; }
  .section-header p { font-size: 0.92rem; }
  .adv-grid { grid-template-columns: 1fr; gap: 16px; }
  .adv-card { padding: 26px 20px; }
  .scope-grid { grid-template-columns: 1fr; gap: 20px; }
  .scope-card-inner { padding: 24px 20px; }
  .category-video { padding: 16px 20px 24px; }
  .about-image { min-height: 300px; }
  .contact-form { padding: 24px 20px; }
  .contact-info h3 { font-size: 1.35rem; }
  .footer-grid { grid-template-columns: 1fr; gap: 28px; }
  .cert-strip { gap: 20px; padding: 28px 0; }
  .output-features { gap: 14px; }
  .output-feature { padding: 16px; }
  .output-feature .of-icon { width: 40px; height: 40px; font-size: 1.2rem; }

  /* 编辑提示栏 */
  .edit-hint-bar { left: 16px; right: 16px; bottom: 16px; max-width: none; }
}

/* 小屏手机 */
@media (max-width: 380px) {
  .hero h1 { font-size: 1.45rem; }
  .hero-badge { font-size: 0.75rem; padding: 4px 12px; }
  .scope-card .tags { gap: 4px; }
  .scope-card .tag { padding: 2px 9px; font-size: 0.7rem; }
}

/* ==================== Accessibility (a11y) ==================== */

/* Skip-link：键盘/读屏用户跳到正文；默认隐藏，聚焦时显示 */
.skip-link {
  position: absolute;
  top: -40px;
  left: 8px;
  background: var(--primary);
  color: #fff;
  padding: 8px 14px;
  border-radius: 6px;
  z-index: 9999;
  font-weight: 600;
  text-decoration: none;
  transition: top 0.2s;
}
.skip-link:focus { top: 8px; outline: 3px solid #fbbf24; outline-offset: 2px; }

/* 统一键盘聚焦轮廓（鼠标用户不可见，键盘用户清晰可见） */
:focus-visible {
  outline: 3px solid var(--primary);
  outline-offset: 2px;
  border-radius: 4px;
}
/* 编辑模式下，编辑器自带的内嵌轮廓优先级更高，避免双重轮廓 */
body.editing *:focus-visible { outline-color: #f59e0b; }

/* 尊重用户系统的"减少动效"偏好：禁用滚动动画与平滑滚动 */
@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after {
    animation-duration: 0.001ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.001ms !important;
    scroll-behavior: auto !important;
  }
  .fade-up { opacity: 1 !important; transform: none !important; }
}

/* 屏幕阅读器专用：仅供盲文/语音阅读的视觉隐藏 */
.sr-only {
  position: absolute;
  width: 1px;
  height: 1px;
  padding: 0;
  margin: -1px;
  overflow: hidden;
  clip: rect(0, 0, 0, 0);
  white-space: nowrap;
  border: 0;
}

/* ============== FAQ 常见问题（语义 details/summary） ============== */
.faq-grid {
  max-width: 880px;
  margin: 0 auto;
  display: flex;
  flex-direction: column;
  gap: 12px;
}
.faq-item {
  border: 1px solid #e2e8f0;
  border-radius: 12px;
  background: var(--white);
  overflow: hidden;
  transition: box-shadow 0.2s ease, border-color 0.2s ease;
}
.faq-item:hover { border-color: #cbd5e1; }
.faq-item[open] {
  box-shadow: 0 4px 18px rgba(14, 165, 233, 0.08);
  border-color: var(--primary);
}
.faq-item > summary {
  padding: 18px 56px 18px 22px;
  font-weight: 600;
  font-size: 1.02rem;
  color: var(--text);
  cursor: pointer;
  list-style: none;
  position: relative;
  user-select: none;
  line-height: 1.5;
}
.faq-item > summary::-webkit-details-marker { display: none; }
.faq-item > summary::marker { display: none; }
.faq-item > summary:focus-visible {
  outline: 2px solid var(--primary);
  outline-offset: -2px;
  border-radius: 6px;
}
.faq-item > summary::after {
  content: '+';
  position: absolute;
  right: 22px;
  top: 50%;
  transform: translateY(-50%);
  width: 28px;
  height: 28px;
  border-radius: 50%;
  background: rgba(14, 165, 233, 0.1);
  color: var(--primary);
  font-size: 1.2rem;
  font-weight: 400;
  line-height: 28px;
  text-align: center;
  transition: background 0.2s ease, transform 0.2s ease;
}
.faq-item[open] > summary::after {
  content: '−';
  background: var(--primary);
  color: var(--white);
}
.faq-item > summary:hover::after {
  background: rgba(14, 165, 233, 0.18);
}
.faq-item > .faq-answer {
  padding: 0 22px 20px;
  color: var(--text-light);
  line-height: 1.75;
  font-size: 0.97rem;
  border-top: 1px solid #f1f5f9;
  margin-top: 0;
}
.faq-item > .faq-answer > p { margin: 14px 0 0; }
/* 尊重用户的"减少动效"偏好：折叠状态切换时不转圈 */
@media (prefers-reduced-motion: reduce) {
  .faq-item, .faq-item > summary::after { transition: none !important; }
}
@media (max-width: 640px) {
  .faq-item > summary { font-size: 0.95rem; padding: 16px 50px 16px 18px; }
  .faq-item > .faq-answer { padding: 0 18px 18px; font-size: 0.92rem; }
  .faq-item > summary::after { right: 18px; }
}