/* ============================================================
   武汉星辰视界文化科技有限公司 · 深色科技风 共享样式
   设计基线：demo2-深色科技风（颜色体系见子页面设计调研报告）
   ============================================================ */
:root {
    --bg-primary: #0a0e27;
    --bg-secondary: #111327;
    --bg-card: #1a1f3a;
    --bg-card-hover: #232848;
    --accent: #4f8cff;
    --accent2: #00d4ff;
    --accent-pink: #ff6b9d;
    --accent-purple: #a855f7;
    --text-primary: #ffffff;
    --text-secondary: #8b9dc3;
    --text-muted: #5a6a8a;
    --border: rgba(79, 140, 255, 0.2);
    --gradient-primary: linear-gradient(135deg, #4f8cff 0%, #00d4ff 100%);
    --gradient-accent: linear-gradient(135deg, #4f8cff 0%, #a855f7 50%, #ff6b9d 100%);
    --shadow-glow: 0 0 30px rgba(79, 140, 255, 0.3);
    --shadow-card: 0 10px 40px rgba(0, 0, 0, 0.3);
    --radius-sm: 8px;
    --radius-md: 12px;
    --radius-lg: 20px;
    --transition: all 0.3s ease;
    --container: 1400px;
}

* { margin: 0; padding: 0; box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
    font-family: 'Noto Sans SC', -apple-system, BlinkMacSystemFont, 'PingFang SC', 'Microsoft YaHei', sans-serif;
    background: var(--bg-primary);
    color: var(--text-primary);
    line-height: 1.6;
    overflow-x: hidden;
    -webkit-font-smoothing: antialiased;
}
a { color: inherit; text-decoration: none; transition: var(--transition); }
img { max-width: 100%; height: auto; display: block; }
ul { list-style: none; }

.container { max-width: var(--container); margin: 0 auto; padding: 0 40px; }
.main-content { position: relative; z-index: 1; }

/* ---------- 星空背景 ---------- */
.starfield { position: fixed; inset: 0; pointer-events: none; z-index: 0; overflow: hidden; }
.starfield::before, .starfield::after {
    content: ''; position: absolute; inset: 0;
    background-image:
        radial-gradient(2px 2px at 20px 30px, rgba(255,255,255,0.8), transparent),
        radial-gradient(2px 2px at 40px 70px, rgba(79,140,255,0.6), transparent),
        radial-gradient(1px 1px at 90px 40px, rgba(255,255,255,0.5), transparent),
        radial-gradient(2px 2px at 160px 120px, rgba(0,212,255,0.5), transparent),
        radial-gradient(1px 1px at 230px 80px, rgba(255,255,255,0.4), transparent),
        radial-gradient(2px 2px at 300px 150px, rgba(79,140,255,0.4), transparent),
        radial-gradient(1px 1px at 380px 60px, rgba(255,255,255,0.6), transparent),
        radial-gradient(2px 2px at 450px 200px, rgba(0,212,255,0.5), transparent);
    background-repeat: repeat; background-size: 500px 300px;
    animation: twinkle 8s ease-in-out infinite;
}
.starfield::after { background-size: 400px 250px; animation-delay: -4s; opacity: 0.5; }
@keyframes twinkle { 0%, 100% { opacity: 0.85; } 50% { opacity: 0.4; } }

/* ---------- 导航 ---------- */
.navbar {
    position: fixed; top: 0; left: 0; right: 0; z-index: 1000;
    background: rgba(10, 14, 39, 0.8);
    backdrop-filter: blur(20px);
    border-bottom: 1px solid var(--border);
    transition: var(--transition);
}
.navbar.scrolled { background: rgba(10, 14, 39, 0.97); box-shadow: 0 5px 30px rgba(0,0,0,0.35); }
.navbar .container { display: flex; align-items: center; justify-content: space-between; height: 80px; }
.logo { display: flex; align-items: center; gap: 12px; }
.logo-icon {
    width: 44px; height: 44px; border-radius: 12px;
    background: var(--gradient-primary); display: flex; align-items: center; justify-content: center;
    font-size: 22px; font-weight: 700; box-shadow: var(--shadow-glow);
}
.logo-text { font-size: 20px; font-weight: 700; letter-spacing: 2px; background: var(--gradient-primary); -webkit-background-clip: text; -webkit-text-fill-color: transparent; background-clip: text; }
.nav-links { display: flex; align-items: center; gap: 8px; }
.nav-link { padding: 10px 18px; border-radius: var(--radius-sm); color: var(--text-secondary); font-size: 15px; font-weight: 500; position: relative; }
.nav-link:hover, .nav-link.active { color: var(--text-primary); background: rgba(79,140,255,0.1); }
.nav-dropdown { position: relative; }
.nav-dropdown-content {
    position: absolute; top: 100%; left: 50%; transform: translateX(-50%) translateY(10px);
    background: var(--bg-card); border: 1px solid var(--border); border-radius: var(--radius-md);
    padding: 10px; min-width: 200px; opacity: 0; visibility: hidden; transition: var(--transition);
    box-shadow: var(--shadow-card); z-index: 10;
}
.nav-dropdown:hover .nav-dropdown-content { opacity: 1; visibility: visible; transform: translateX(-50%) translateY(0); }
.nav-dropdown-content a { display: block; padding: 10px 16px; border-radius: var(--radius-sm); color: var(--text-secondary); font-size: 14px; }
.nav-dropdown-content a:hover { background: rgba(79,140,255,0.15); color: var(--text-primary); }
.nav-cta { background: var(--gradient-primary); color: #fff; padding: 11px 22px; border-radius: var(--radius-sm); font-size: 14px; font-weight: 600; }
.nav-cta:hover { transform: translateY(-2px); box-shadow: 0 10px 30px rgba(79,140,255,0.4); }
.mobile-menu-btn { display: none; background: none; border: none; cursor: pointer; padding: 10px; }
.mobile-menu-btn span { display: block; width: 24px; height: 2px; background: var(--text-primary); margin: 5px 0; transition: var(--transition); border-radius: 2px; }
.mobile-menu-btn.open span:nth-child(1) { transform: translateY(7px) rotate(45deg); }
.mobile-menu-btn.open span:nth-child(2) { opacity: 0; }
.mobile-menu-btn.open span:nth-child(3) { transform: translateY(-7px) rotate(-45deg); }
/* 移动抽屉/遮罩：桌面隐藏，移动端在媒体查询内启用 */
.mobile-overlay, .mobile-drawer { display: none; }
body.nav-open { overflow: hidden; }

/* ---------- 按钮 ---------- */
.btn { display: inline-flex; align-items: center; justify-content: center; gap: 8px; padding: 14px 32px; border-radius: var(--radius-md); font-size: 15px; font-weight: 600; cursor: pointer; border: none; transition: var(--transition); }
.btn-primary { background: var(--gradient-primary); color: #fff; box-shadow: 0 4px 20px rgba(79,140,255,0.4); }
.btn-primary:hover { transform: translateY(-2px); box-shadow: 0 6px 30px rgba(79,140,255,0.55); }
.btn-secondary { background: transparent; color: var(--text-primary); border: 2px solid var(--accent); }
.btn-secondary:hover { background: var(--accent); box-shadow: var(--shadow-glow); }
.btn-glow { position: relative; overflow: hidden; }
.btn-glow::before { content: ''; position: absolute; top: 0; left: -100%; width: 100%; height: 100%; background: linear-gradient(90deg, transparent, rgba(255,255,255,0.2), transparent); transition: left 0.5s; }
.btn-glow:hover::before { left: 100%; }

/* ---------- 通用区块 ---------- */
.section { padding: 100px 0; position: relative; z-index: 1; }
.section.alt { background: var(--bg-secondary); }
.section-header { text-align: center; margin-bottom: 60px; }
.section-tag { display: inline-block; padding: 6px 16px; background: rgba(79,140,255,0.1); border: 1px solid var(--border); border-radius: 20px; font-size: 13px; color: var(--accent); margin-bottom: 16px; text-transform: uppercase; letter-spacing: 2px; }
.section-title { font-size: 42px; font-weight: 700; margin-bottom: 16px; }
.section-title .hl { color: var(--accent2); }
.section-desc { font-size: 18px; color: var(--text-secondary); max-width: 700px; margin: 0 auto; }

.card { background: var(--bg-card); border: 1px solid var(--border); border-radius: var(--radius-lg); padding: 32px; transition: var(--transition); }
.card:hover { transform: translateY(-5px); border-color: var(--accent); box-shadow: var(--shadow-glow); }
.grid-2 { display: grid; grid-template-columns: repeat(2, 1fr); gap: 30px; }
.grid-3 { display: grid; grid-template-columns: repeat(3, 1fr); gap: 30px; }

/* ---------- Hero ---------- */
.hero { position: relative; min-height: 100vh; min-height: 100svh; display: flex; align-items: center; padding: 120px 0 80px; overflow: hidden; }
.hero-bg-gradient { position: absolute; top: -30%; right: -10%; width: 800px; height: 800px; background: radial-gradient(circle, rgba(79,140,255,0.35) 0%, transparent 70%); filter: blur(100px); animation: float 8s ease-in-out infinite; }
@keyframes float { 0%, 100% { transform: translateY(0); } 50% { transform: translateY(-24px); } }
.hero .container { position: relative; z-index: 2; }
.hero-tag { display: inline-flex; align-items: center; gap: 12px; font-size: 13px; color: var(--accent2); letter-spacing: 3px; margin-bottom: 28px; padding: 8px 16px; background: rgba(79,140,255,0.1); border: 1px solid rgba(79,140,255,0.3); border-radius: 100px; }
.hero-tag::before { content: ''; width: 8px; height: 8px; background: var(--accent); border-radius: 50%; animation: pulse 2s infinite; }
@keyframes pulse { 0%, 100% { box-shadow: 0 0 0 0 rgba(79,140,255,0.6); } 50% { box-shadow: 0 0 0 6px rgba(79,140,255,0); } }
.hero h1 { font-size: clamp(40px, 6vw, 76px); font-weight: 700; line-height: 1.15; margin-bottom: 28px; max-width: 920px; }
.hero h1 .gradient-text { background: linear-gradient(135deg, var(--accent2), var(--accent-purple), var(--accent)); background-size: 200% 200%; -webkit-background-clip: text; -webkit-text-fill-color: transparent; background-clip: text; animation: grad-shift 5s ease infinite; }
@keyframes grad-shift { 0% { background-position: 0% 50%; } 50% { background-position: 100% 50%; } 100% { background-position: 0% 50%; } }
.hero-desc { font-size: 18px; color: var(--text-secondary); max-width: 600px; line-height: 1.8; margin-bottom: 40px; }
.hero-buttons { display: flex; gap: 18px; flex-wrap: wrap; }

/* ---------- 数据背书 ---------- */
.stats-grid { display: grid; grid-template-columns: repeat(4, 1fr); border-top: 1px solid var(--border); border-bottom: 1px solid var(--border); }
.stat-item { padding: 56px 30px; text-align: center; border-right: 1px solid var(--border); }
.stat-item:last-child { border-right: none; }
.stat-number { font-size: 56px; font-weight: 700; background: linear-gradient(135deg, #fff, var(--accent2)); -webkit-background-clip: text; -webkit-text-fill-color: transparent; background-clip: text; line-height: 1; margin-bottom: 12px; }
.stat-label { font-size: 14px; color: var(--text-secondary); letter-spacing: 2px; }

/* ---------- 服务卡片 ---------- */
.services-grid { display: grid; grid-template-columns: repeat(5, 1fr); gap: 22px; }
.service-card { background: var(--bg-card); border: 1px solid var(--border); border-radius: var(--radius-lg); padding: 36px 24px; text-align: center; transition: var(--transition); cursor: pointer; position: relative; overflow: hidden; }
.service-card::before { content: ''; position: absolute; top: 0; left: 0; right: 0; height: 3px; background: var(--gradient-primary); transform: scaleX(0); transition: transform 0.4s; }
.service-card:hover { transform: translateY(-8px); border-color: var(--accent); box-shadow: var(--shadow-card); }
.service-card:hover::before { transform: scaleX(1); }
.service-icon { width: 64px; height: 64px; margin: 0 auto 22px; background: linear-gradient(135deg, rgba(79,140,255,0.2), rgba(79,140,255,0.05)); border-radius: 16px; display: flex; align-items: center; justify-content: center; transition: var(--transition); }
.service-card:hover .service-icon { background: var(--gradient-primary); }
.service-icon svg { width: 32px; height: 32px; stroke: var(--accent2); transition: stroke 0.3s; }
.service-card:hover .service-icon svg { stroke: #fff; }
.service-card h3 { font-size: 18px; font-weight: 500; margin-bottom: 10px; }
.service-card p { font-size: 13px; color: var(--text-secondary); line-height: 1.6; }

/* ---------- 案例 ---------- */
.portfolio-header { display: flex; justify-content: space-between; align-items: flex-end; margin-bottom: 50px; gap: 24px; flex-wrap: wrap; }
.portfolio-link { color: var(--accent2); font-size: 14px; display: inline-flex; align-items: center; gap: 8px; }
.portfolio-link:hover { gap: 14px; }
.portfolio-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 24px; }
.portfolio-item { position: relative; border-radius: var(--radius-lg); overflow: hidden; aspect-ratio: 4/3; background: var(--bg-card); }
.portfolio-item img { width: 100%; height: 100%; object-fit: cover; transition: transform 0.6s; }
.portfolio-item:hover img { transform: scale(1.08); }
.portfolio-overlay { position: absolute; inset: 0; background: linear-gradient(to top, rgba(10,14,39,0.95), rgba(10,14,39,0.3), transparent); display: flex; flex-direction: column; justify-content: flex-end; padding: 28px; opacity: 0; transition: opacity 0.4s; }
.portfolio-item:hover .portfolio-overlay { opacity: 1; }
.portfolio-tag { font-size: 12px; color: var(--accent2); letter-spacing: 2px; margin-bottom: 8px; }
.portfolio-overlay h4 { font-size: 19px; font-weight: 600; margin-bottom: 6px; }
.portfolio-overlay p { font-size: 14px; color: var(--text-secondary); }

/* ---------- 流程 ---------- */
.process-steps { display: grid; grid-template-columns: repeat(2, 1fr); gap: 20px; }
.step { display: flex; gap: 20px; background: var(--bg-card); border: 1px solid var(--border); border-radius: var(--radius-lg); padding: 28px; }
.step-num { width: 54px; height: 54px; flex-shrink: 0; background: var(--gradient-primary); border-radius: 50%; display: flex; align-items: center; justify-content: center; font-size: 22px; font-weight: 700; }
.step h4 { font-size: 19px; margin-bottom: 6px; }
.step p { font-size: 14px; color: var(--text-secondary); }

/* ---------- FAQ（GEO 关键） ---------- */
.faq-list { max-width: 860px; margin: 0 auto; }
.faq-item { background: var(--bg-card); border: 1px solid var(--border); border-radius: var(--radius-md); margin-bottom: 14px; overflow: hidden; }
.faq-q { width: 100%; text-align: left; background: none; border: none; color: var(--text-primary); font-size: 17px; font-weight: 500; padding: 22px 26px; cursor: pointer; display: flex; justify-content: space-between; align-items: center; gap: 16px; font-family: inherit; }
.faq-q .ico { color: var(--accent2); font-size: 22px; transition: transform 0.3s; flex-shrink: 0; }
.faq-item.open .faq-q .ico { transform: rotate(45deg); }
.faq-a { max-height: 0; overflow: hidden; transition: max-height 0.35s ease; }
.faq-a-inner { padding: 0 26px 22px; color: var(--text-secondary); font-size: 15px; line-height: 1.8; }

/* ---------- 面包屑 ---------- */
.breadcrumb { display: flex; align-items: center; gap: 10px; margin-bottom: 26px; font-size: 14px; color: var(--text-muted); }
.breadcrumb a { color: var(--text-secondary); }
.breadcrumb a:hover { color: var(--accent); }

/* ---------- 页头（子页） ---------- */
.page-header { padding: 160px 0 90px; text-align: center; position: relative; overflow: hidden; background: linear-gradient(135deg, rgba(79,140,255,0.1) 0%, rgba(0,212,255,0.05) 100%); }
.page-header h1 { font-size: 52px; font-weight: 700; margin-bottom: 18px; background: var(--gradient-primary); -webkit-background-clip: text; -webkit-text-fill-color: transparent; background-clip: text; }
.page-header p { font-size: 18px; color: var(--text-secondary); max-width: 620px; margin: 0 auto; }

/* ---------- 服务详情 ---------- */
.service-hero { padding: 160px 0 90px; position: relative; overflow: hidden; }
.service-hero::before { content: ''; position: absolute; inset: 0; background: radial-gradient(ellipse at center, rgba(79,140,255,0.15) 0%, transparent 70%); }
.service-hero .container { display: flex; align-items: center; gap: 60px; }
.service-hero-icon { width: 120px; height: 120px; flex-shrink: 0; background: var(--gradient-primary); border-radius: var(--radius-lg); display: flex; align-items: center; justify-content: center; font-size: 52px; box-shadow: var(--shadow-glow); }
.service-hero h1 { font-size: 46px; font-weight: 700; margin-bottom: 18px; background: var(--gradient-primary); -webkit-background-clip: text; -webkit-text-fill-color: transparent; background-clip: text; }
.service-hero p { font-size: 18px; color: var(--text-secondary); line-height: 1.8; margin-bottom: 24px; }
.service-list { list-style: none; }
.service-list li { display: flex; align-items: center; gap: 12px; padding: 11px 0; border-bottom: 1px solid var(--border); color: var(--text-secondary); }
.service-list li:last-child { border-bottom: none; }
.service-list li::before { content: '✓'; color: var(--accent); font-weight: 700; }
.card-icon { width: 64px; height: 64px; background: var(--gradient-primary); border-radius: var(--radius-md); display: flex; align-items: center; justify-content: center; font-size: 30px; margin-bottom: 18px; }
.card-title { font-size: 21px; font-weight: 600; margin-bottom: 10px; }
.card-text { color: var(--text-secondary); font-size: 15px; line-height: 1.7; }
.case-card { background: var(--bg-card); border: 1px solid var(--border); border-radius: var(--radius-lg); overflow: hidden; transition: var(--transition); }
.case-card:hover { transform: translateY(-5px); border-color: var(--accent); box-shadow: var(--shadow-glow); }
.case-card img { width: 100%; height: 210px; object-fit: cover; }
.case-card-content { padding: 22px; }
.case-card h4 { font-size: 18px; margin-bottom: 8px; }
.case-card p { color: var(--text-secondary); font-size: 14px; margin-bottom: 12px; }
.case-tag { display: inline-block; padding: 4px 12px; background: rgba(79,140,255,0.1); border-radius: 20px; font-size: 12px; color: var(--accent); }

/* ---------- 案例中心 ---------- */
.filter-bar { display: flex; flex-wrap: wrap; gap: 12px; justify-content: center; margin-bottom: 44px; }
.filter-btn { padding: 9px 22px; border-radius: 999px; border: 1px solid var(--border); background: transparent; color: var(--text-secondary); font-size: 14px; cursor: pointer; transition: var(--transition); font-family: inherit; }
.filter-btn:hover, .filter-btn.active { background: var(--gradient-primary); color: #fff; border-color: transparent; }

/* ---------- 联系 ---------- */
.contact-grid { display: grid; grid-template-columns: 1fr 1fr; gap: 50px; align-items: start; }
.contact-info p { display: flex; align-items: center; gap: 14px; color: var(--text-secondary); font-size: 16px; margin-bottom: 18px; }
.contact-info .ico { width: 42px; height: 42px; flex-shrink: 0; background: rgba(79,140,255,0.12); border-radius: 10px; display: flex; align-items: center; justify-content: center; font-size: 20px; }
.form-field { margin-bottom: 20px; }
.form-field label { display: block; font-size: 14px; color: var(--text-secondary); margin-bottom: 8px; }
.form-field input, .form-field textarea, .form-field select { width: 100%; padding: 14px 16px; background: var(--bg-card); border: 1px solid var(--border); border-radius: var(--radius-sm); color: var(--text-primary); font-size: 15px; font-family: inherit; transition: var(--transition); }
.form-field input:focus, .form-field textarea:focus, .form-field select:focus { outline: none; border-color: var(--accent); box-shadow: 0 0 0 3px rgba(79,140,255,0.15); }
.form-field textarea { min-height: 130px; resize: vertical; }
.form-note { font-size: 13px; color: var(--text-muted); margin-top: 10px; }

/* ---------- 文章列表 ---------- */
.news-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 28px; }
.news-card { background: var(--bg-card); border: 1px solid var(--border); border-radius: var(--radius-lg); overflow: hidden; transition: var(--transition); }
.news-card:hover { transform: translateY(-5px); border-color: var(--accent); box-shadow: var(--shadow-glow); }
.news-card .thumb { height: 190px; background: linear-gradient(135deg, #1a2a5e, #0e3a52); display: flex; align-items: center; justify-content: center; font-size: 40px; overflow: hidden; }
.news-card .thumb img { width: 100%; height: 100%; object-fit: cover; display: block; }
.news-card-content { padding: 22px; }
.news-meta { font-size: 13px; color: var(--accent2); margin-bottom: 10px; }
.news-card h4 { font-size: 18px; margin-bottom: 8px; line-height: 1.5; }
.news-card p { font-size: 14px; color: var(--text-secondary); }

/* ---------- 页脚 ---------- */
.footer { background: var(--bg-secondary); border-top: 1px solid var(--border); padding: 72px 0 30px; margin-top: 100px; position: relative; z-index: 1; }
.footer-grid { display: grid; grid-template-columns: 2fr 1fr 1fr 1fr 1fr; gap: 56px; margin-bottom: 56px; }
.footer-brand { max-width: 360px; }
.footer-brand .logo { margin-bottom: 18px; }
.footer-brand p { color: var(--text-secondary); font-size: 15px; line-height: 1.7; }
.footer-title { font-size: 17px; font-weight: 600; margin-bottom: 22px; }
.footer-links a { display: block; color: var(--text-secondary); padding: 8px 0; font-size: 15px; }
.footer-links a:hover { color: var(--accent); padding-left: 5px; }
.footer-contact p { display: flex; align-items: center; gap: 12px; color: var(--text-secondary); font-size: 15px; margin-bottom: 14px; }
.footer-bottom { padding-top: 28px; border-top: 1px solid var(--border); display: grid; grid-template-columns: 1fr auto 1fr; align-items: center; gap: 14px; font-size: 13px; color: var(--text-muted); }
.footer-social { display: flex; gap: 14px; justify-self: end; }
.footer-social a { width: 38px; height: 38px; background: var(--bg-card); border-radius: 50%; display: flex; align-items: center; justify-content: center; color: var(--text-secondary); font-size: 14px; }
.footer-social a:hover { background: var(--accent); color: #fff; }
.footer-icp { text-align: center; font-size: 12px; color: var(--text-muted); }
.footer-icp a { color: var(--text-muted); text-decoration: none; transition: var(--transition); }
.footer-icp a:hover { color: var(--accent); }

/* ---------- 返回顶部 ---------- */
.back-to-top { position: fixed; bottom: 30px; right: 30px; width: 50px; height: 50px; background: var(--gradient-primary); border-radius: 50%; display: flex; align-items: center; justify-content: center; cursor: pointer; opacity: 0; visibility: hidden; transition: var(--transition); z-index: 999; box-shadow: var(--shadow-glow); color: #fff; font-size: 20px; }
.back-to-top.visible { opacity: 1; visibility: visible; }
.back-to-top:hover { transform: translateY(-5px); }

/* ---------- 滚动揭示动画 ---------- */
.reveal { opacity: 0; transform: translateY(30px); transition: opacity 0.7s ease, transform 0.7s ease; }
.reveal.in { opacity: 1; transform: translateY(0); }

/* 移动端底部快捷栏（桌面隐藏，≤768 显示） */
.mobile-tabbar { display: none; position: fixed; left: 0; right: 0; bottom: 0; z-index: 1000; background: rgba(17,19,39,.96); backdrop-filter: blur(16px); border-top: 1px solid var(--border); padding: 10px 14px calc(10px + env(safe-area-inset-bottom)); gap: 12px; }
.mobile-tabbar a { flex: 1; display: flex; align-items: center; justify-content: center; gap: 8px; padding: 13px 0; border-radius: 12px; font-size: 15px; font-weight: 600; color: #fff; }
.mobile-tabbar .tab-phone { background: var(--gradient-primary); }
.mobile-tabbar .tab-msg { background: rgba(79,140,255,.16); border: 1px solid var(--border); color: var(--text-primary); }

/* ---------- 响应式 ---------- */
@media (max-width: 1200px) {
    .services-grid { grid-template-columns: repeat(3, 1fr); }
    .footer-grid { grid-template-columns: repeat(2, 1fr); gap: 40px; }
    .stats-grid { grid-template-columns: repeat(4, 1fr); }
}

/* 平板及移动：启用抽屉导航 */
@media (max-width: 992px) {
    .container { padding: 0 24px; }
    .nav-links, .nav-cta { display: none; }
    .mobile-menu-btn { display: block; }
    .navbar .container { height: 68px; }

    /* 遮罩 + 右侧抽屉 */
    .mobile-overlay { display: block; position: fixed; inset: 0; background: rgba(5, 8, 20, 0.6); backdrop-filter: blur(2px); opacity: 0; visibility: hidden; transition: opacity .3s ease, visibility .3s ease; z-index: 1001; }
    .mobile-overlay.open { opacity: 1; visibility: visible; }
    .mobile-drawer { display: flex; flex-direction: column; position: fixed; top: 0; right: 0; bottom: 0; width: min(82vw, 340px); background: var(--bg-secondary); border-left: 1px solid var(--border); transform: translateX(100%); visibility: hidden; transition: transform .32s ease, visibility .32s ease; z-index: 1002; padding: calc(env(safe-area-inset-top) + 18px) 22px calc(env(safe-area-inset-bottom) + 22px); overflow-y: auto; box-shadow: -12px 0 40px rgba(0,0,0,.45); }
    .mobile-drawer.open { transform: translateX(0); visibility: visible; }
    .mobile-drawer-head { display: flex; justify-content: space-between; align-items: center; margin-bottom: 18px; padding: 0 4px; }
    .mobile-close { background: none; border: none; color: var(--text-primary); font-size: 30px; line-height: 1; cursor: pointer; padding: 4px 8px; }
    .mobile-drawer-links { display: flex; flex-direction: column; gap: 4px; }
    .mobile-drawer-links > a { padding: 14px 12px; font-size: 17px; color: var(--text-primary); border-radius: var(--radius-sm); }
    .mobile-drawer-links > a:active { background: rgba(79,140,255,.12); }
    .mobile-sub { margin: 8px 0 4px; padding: 10px 0 4px; border-top: 1px solid var(--border); }
    .mobile-sub-title { font-size: 12px; color: var(--text-muted); letter-spacing: 2px; padding: 10px 12px 6px; text-transform: uppercase; }
    .mobile-sub a { padding: 11px 12px 11px 26px; font-size: 15px; color: var(--text-secondary); }
    .mobile-sub a:active { color: var(--text-primary); }
    .mobile-cta { margin-top: 18px; background: var(--gradient-primary); color: #fff !important; text-align: center; font-weight: 600; padding: 14px; }

    /* 栅格与间距 */
    .stats-grid { grid-template-columns: repeat(2, 1fr); }
    .stat-item:nth-child(2) { border-right: none; }
    .stat-item:nth-child(1), .stat-item:nth-child(2) { border-bottom: 1px solid var(--border); }
    .services-grid { grid-template-columns: repeat(2, 1fr); }
    .portfolio-grid, .news-grid { grid-template-columns: repeat(2, 1fr); }
    .grid-3 { grid-template-columns: repeat(2, 1fr); }
    .grid-2, .process-steps, .contact-grid, .service-hero .container { grid-template-columns: 1fr; flex-direction: column; text-align: center; }
    .section { padding: 72px 0; }
    .page-header { padding: 130px 0 56px; }
    .page-header h1 { font-size: 38px; }
    .hero { padding: 104px 0 64px; }
    /* 触屏无 hover：案例标题常显，保证信息可读 */
    .portfolio-overlay { opacity: 1; background: linear-gradient(to top, rgba(10,14,39,.94) 8%, rgba(10,14,39,.25) 68%, transparent); padding: 22px; }
    .portfolio-tag { font-size: 11px; }
}

/* 手机 */
@media (max-width: 768px) {
    .hero h1 { font-size: 32px; }
    .section-title { font-size: 28px; }
    .services-grid, .portfolio-grid, .news-grid, .grid-3 { grid-template-columns: 1fr; }
    .footer-grid { grid-template-columns: 1fr; gap: 34px; }
    .footer-bottom { grid-template-columns: 1fr; justify-items: center; text-align: center; gap: 14px; }
    .footer-social { justify-self: center; }
    .hero-buttons { flex-direction: column; }
    .btn { justify-content: center; width: 100%; }
    .back-to-top { display: none; }
    /* 移动端底部快捷栏 */
    .mobile-tabbar { display: flex; }
    body { padding-bottom: calc(64px + env(safe-area-inset-bottom)); }
    .footer { margin-top: 64px; }
}

/* 小屏手机：更紧凑、更像 App 的布局 */
@media (max-width: 600px) {
    .container { padding: 0 18px; }
    .section { padding: 56px 0; }
    .page-header { padding: 112px 0 44px; }
    .page-header h1 { font-size: 30px; }
    .section-title { font-size: 25px; }
    .section-desc { font-size: 15px; }
    .hero { padding: 96px 0 56px; }
    .hero h1 { font-size: 28px; }
    .hero-desc { font-size: 15px; margin-bottom: 30px; }
    .hero-tag { font-size: 12px; }
    .stat-number { font-size: 40px; }
    .stat-item { padding: 36px 16px; }
    .stat-label { font-size: 12px; }
    .services-grid { grid-template-columns: 1fr; }
    /* 服务卡横向紧凑排列，节省竖向空间 */
    .service-card { display: flex; align-items: center; text-align: left; gap: 16px; padding: 16px 18px; }
    .service-icon { width: 48px; height: 48px; margin: 0; flex-shrink: 0; border-radius: 12px; }
    .service-card h3 { font-size: 17px; margin-bottom: 4px; }
    .service-card p { font-size: 12px; }
    .card { padding: 22px; }
    .case-card img { height: 180px; }
    .news-card .thumb { height: 160px; }
    .portfolio-grid { gap: 16px; }
    .filter-bar { gap: 8px; margin-bottom: 30px; }
    .filter-btn { padding: 8px 16px; font-size: 13px; }
    .form-field input, .form-field textarea, .form-field select { font-size: 16px; }
    .footer { padding: 56px 0 28px; }
    .footer-grid { gap: 28px; }
}

/* 移动端底部快捷栏（基础隐藏，≤768 显示）—— 必须在媒体查询前定义 base，否则后置会覆盖 media 的 display:flex */