/* ============================================================
   渠道人联盟官网 - 统一样式系统
   风格：科技蓝渐变 + 玻璃拟态 + 轻阴影 + 入场动画
   版本：v=20261013a
   ============================================================ */

:root {
    --primary: #2563eb;
    --primary-light: #3b82f6;
    --primary-dark: #1e40af;
    --gradient: linear-gradient(135deg, #3b82f6 0%, #2563eb 50%, #1e40af 100%);
    --gradient-soft: linear-gradient(135deg, rgba(59,130,246,.12), rgba(37,99,235,.06));
    --bg: #f5f7fa;
    --bg-dark: #0b1530;
    --text: #1f2937;
    --muted: #6b7280;
    --card: #ffffff;
    --border: #e5e7eb;
    --radius: 16px;
    --radius-sm: 10px;
    --shadow: 0 10px 30px rgba(15, 23, 42, .08);
    --shadow-lg: 0 20px 50px rgba(15, 23, 42, .14);
    --maxw: 1180px;
    --nav-h: 68px;
}

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

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;
    -webkit-font-smoothing: antialiased;
}

a { color: inherit; text-decoration: none; }
img { max-width: 100%; display: block; }
ul { list-style: none; }

.container { width: 100%; max-width: var(--maxw); margin: 0 auto; padding: 0 20px; }

/* ---------- 按钮 ---------- */
.btn {
    display: inline-flex; align-items: center; justify-content: center; gap: 8px;
    padding: 13px 28px; border-radius: 999px; font-weight: 600; font-size: 15px;
    cursor: pointer; border: none; transition: all .25s ease; white-space: nowrap;
}
.btn-primary { background: var(--gradient); color: #fff; box-shadow: 0 8px 22px rgba(37,99,235,.35); }
.btn-primary:hover { transform: translateY(-2px); box-shadow: 0 14px 32px rgba(37,99,235,.45); }
.btn-ghost { background: rgba(255,255,255,.12); color: #fff; border: 1px solid rgba(255,255,255,.45); backdrop-filter: blur(6px); }
.btn-ghost:hover { background: rgba(255,255,255,.22); }
.btn-outline { background: #fff; color: var(--primary); border: 1.5px solid var(--primary); }
.btn-outline:hover { background: var(--gradient-soft); }

/* ---------- 导航 ---------- */
.site-header {
    position: fixed; top: 0; left: 0; right: 0; height: var(--nav-h); z-index: 1000;
    background: rgba(255,255,255,.72); backdrop-filter: blur(14px);
    border-bottom: 1px solid rgba(255,255,255,.5);
    transition: all .3s ease;
}
.site-header.scrolled { background: rgba(255,255,255,.92); box-shadow: 0 6px 24px rgba(15,23,42,.08); }
.nav { height: var(--nav-h); display: flex; align-items: center; justify-content: space-between; }
.brand { display: flex; align-items: center; gap: 10px; font-weight: 800; font-size: 20px; color: var(--primary-dark); }
.brand .logo-mark {
    width: 38px; height: 38px; border-radius: 10px; background: var(--gradient);
    display: grid; place-items: center; color: #fff; font-weight: 900; font-size: 18px;
    box-shadow: 0 6px 16px rgba(37,99,235,.35);
}
.nav-links { display: flex; align-items: center; gap: 6px; }
.nav-links a {
    padding: 9px 16px; border-radius: 999px; font-weight: 500; color: var(--text);
    transition: all .2s ease; font-size: 15px;
}
.nav-links a:hover { background: var(--gradient-soft); color: var(--primary); }
.nav-links a.active { background: var(--gradient); color: #fff; }
.nav-cta { margin-left: 8px; }
.hamburger { display: none; flex-direction: column; gap: 5px; cursor: pointer; padding: 8px; }
.hamburger span { width: 24px; height: 2.5px; background: var(--text); border-radius: 2px; transition: .3s; }

/* ---------- 通用区块 ---------- */
.section { padding: 88px 0; }
.section-alt { background: #fff; }
.section-head { text-align: center; max-width: 720px; margin: 0 auto 52px; }
.section-head .eyebrow {
    display: inline-block; font-size: 13px; font-weight: 700; letter-spacing: 2px;
    color: var(--primary); background: var(--gradient-soft); padding: 5px 16px; border-radius: 999px; margin-bottom: 16px;
}
.section-head h2 { font-size: 34px; line-height: 1.25; margin-bottom: 14px; color: #0f172a; }
.section-head p { color: var(--muted); font-size: 16px; }

/* ---------- Hero ---------- */
.hero {
    position: relative; padding: 150px 0 96px; color: #fff; overflow: hidden;
    background: radial-gradient(circle at 20% 20%, #1e3a8a 0%, transparent 55%),
                radial-gradient(circle at 80% 30%, #2563eb 0%, transparent 50%),
                linear-gradient(135deg, #0b1530, #142a5c 60%, #1e40af);
}
.hero::after {
    content: ""; position: absolute; inset: 0;
    background-image: linear-gradient(rgba(255,255,255,.05) 1px, transparent 1px),
                      linear-gradient(90deg, rgba(255,255,255,.05) 1px, transparent 1px);
    background-size: 46px 46px;
    mask-image: radial-gradient(circle at 50% 30%, #000, transparent 75%);
    pointer-events: none;
}
.hero .container { position: relative; z-index: 2; }
.hero h1 { font-size: 52px; line-height: 1.15; font-weight: 800; margin-bottom: 18px; }
.hero .gradient-text {
    background: linear-gradient(90deg, #7dd3fc, #93c5fd, #c4b5fd);
    -webkit-background-clip: text; background-clip: text; color: transparent;
}
.hero p.lead { font-size: 19px; max-width: 620px; color: rgba(255,255,255,.85); margin-bottom: 32px; }
.hero-cta { display: flex; gap: 14px; flex-wrap: wrap; margin-bottom: 48px; }
.hero-stats { display: flex; gap: 40px; flex-wrap: wrap; }
.hero-stats .stat .num { font-size: 38px; font-weight: 800; color: #fff; }
.hero-stats .stat .label { font-size: 14px; color: rgba(255,255,255,.7); }

/* ---------- 四大主线卡片 ---------- */
.pillars { display: grid; grid-template-columns: repeat(4, 1fr); gap: 22px; }
.pillar {
    background: var(--card); border-radius: var(--radius); padding: 30px 24px; text-align: center;
    box-shadow: var(--shadow); border: 1px solid var(--border); transition: all .3s ease; position: relative; overflow: hidden;
}
.pillar:hover { transform: translateY(-6px); box-shadow: var(--shadow-lg); }
.pillar .ico {
    width: 64px; height: 64px; border-radius: 18px; margin: 0 auto 18px; display: grid; place-items: center;
    background: var(--gradient-soft); color: var(--primary); font-size: 30px;
}
.pillar h3 { font-size: 20px; margin-bottom: 8px; color: #0f172a; }
.pillar p { font-size: 14px; color: var(--muted); }

/* ---------- 特性网格 ---------- */
.feature-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 24px; }
.feature-card {
    background: var(--card); border-radius: var(--radius); padding: 30px; border: 1px solid var(--border);
    box-shadow: var(--shadow); transition: all .3s ease;
}
.feature-card:hover { transform: translateY(-5px); box-shadow: var(--shadow-lg); }
.feature-card .ico { font-size: 32px; margin-bottom: 14px; }
.feature-card h3 { font-size: 19px; margin-bottom: 8px; color: #0f172a; }
.feature-card p { color: var(--muted); font-size: 15px; }

/* ---------- 时间线 ---------- */
.timeline { position: relative; max-width: 820px; margin: 0 auto; padding-left: 28px; }
.timeline::before { content: ""; position: absolute; left: 6px; top: 6px; bottom: 6px; width: 2px; background: linear-gradient(var(--primary), transparent); }
.tl-item { position: relative; padding-bottom: 36px; }
.tl-item::before {
    content: ""; position: absolute; left: -28px; top: 6px; width: 14px; height: 14px; border-radius: 50%;
    background: var(--gradient); box-shadow: 0 0 0 4px rgba(37,99,235,.15);
}
.tl-item .year { font-weight: 800; color: var(--primary); font-size: 18px; }
.tl-item h4 { font-size: 17px; margin: 4px 0 6px; color: #0f172a; }
.tl-item p { color: var(--muted); font-size: 15px; }

/* ---------- 数据条 ---------- */
.stat-band { background: var(--gradient); color: #fff; border-radius: var(--radius); padding: 44px 30px; display: grid; grid-template-columns: repeat(4, 1fr); gap: 20px; text-align: center; }
.stat-band .num { font-size: 44px; font-weight: 800; }
.stat-band .label { font-size: 15px; opacity: .9; margin-top: 4px; }

/* ---------- 步骤 ---------- */
.steps { display: grid; grid-template-columns: repeat(4, 1fr); gap: 22px; counter-reset: step; }
.step { background: var(--card); border-radius: var(--radius); padding: 28px 22px; text-align: center; border: 1px solid var(--border); box-shadow: var(--shadow); position: relative; }
.step .n { width: 46px; height: 46px; border-radius: 50%; background: var(--gradient); color: #fff; font-weight: 800; display: grid; place-items: center; margin: 0 auto 14px; font-size: 20px; }
.step h4 { font-size: 17px; margin-bottom: 6px; color: #0f172a; }
.step p { color: var(--muted); font-size: 14px; }

/* ---------- 表单 ---------- */
.form-wrap { max-width: 640px; margin: 0 auto; background: var(--card); border-radius: var(--radius); padding: 38px; box-shadow: var(--shadow); border: 1px solid var(--border); }
.field { margin-bottom: 18px; }
.field label { display: block; font-weight: 600; margin-bottom: 7px; font-size: 14px; color: #374151; }
.field input, .field textarea, .field select {
    width: 100%; padding: 12px 14px; border: 1.5px solid var(--border); border-radius: var(--radius-sm);
    font-size: 15px; font-family: inherit; transition: border-color .2s, box-shadow .2s; background: #fff;
}
.field input:focus, .field textarea:focus, .field select:focus {
    outline: none; border-color: var(--primary); box-shadow: 0 0 0 3px rgba(37,99,235,.12);
}
.field textarea { resize: vertical; min-height: 110px; }
.form-note { font-size: 13px; color: var(--muted); margin-top: 8px; }
.form-msg { padding: 12px 16px; border-radius: var(--radius-sm); margin-bottom: 18px; font-size: 14px; display: none; }
.form-msg.ok { display: block; background: #ecfdf5; color: #047857; border: 1px solid #a7f3d0; }
.form-msg.err { display: block; background: #fef2f2; color: #b91c1c; border: 1px solid #fecaca; }

/* ---------- 联系信息卡 ---------- */
.contact-cards { display: grid; grid-template-columns: repeat(3, 1fr); gap: 22px; margin-bottom: 40px; }
.contact-card { background: var(--card); border-radius: var(--radius); padding: 28px; text-align: center; border: 1px solid var(--border); box-shadow: var(--shadow); }
.contact-card .ico { font-size: 30px; margin-bottom: 12px; }
.contact-card h4 { font-size: 16px; color: #0f172a; margin-bottom: 6px; }
.contact-card p { color: var(--muted); font-size: 15px; word-break: break-all; }

/* ---------- 页脚 ---------- */
.site-footer { background: var(--bg-dark); color: rgba(255,255,255,.7); padding: 56px 0 28px; margin-top: 0; }
.footer-grid { display: grid; grid-template-columns: 1.6fr 1fr 1fr 1fr; gap: 32px; margin-bottom: 36px; }
.footer-grid .brand { color: #fff; margin-bottom: 14px; }
.footer-grid p.desc { font-size: 14px; max-width: 320px; }
.footer-col h5 { color: #fff; font-size: 15px; margin-bottom: 14px; }
.footer-col a { display: block; font-size: 14px; padding: 5px 0; transition: color .2s; }
.footer-col a:hover { color: #fff; }
.footer-bottom { border-top: 1px solid rgba(255,255,255,.12); padding-top: 22px; text-align: center; font-size: 13px; color: rgba(255,255,255,.5); }

/* ---------- 入场动画 ---------- */
.reveal { opacity: 0; transform: translateY(28px); transition: opacity .7s ease, transform .7s ease; }
.reveal.in { opacity: 1; transform: none; }
@keyframes fadeUp { from { opacity: 0; transform: translateY(24px); } to { opacity: 1; transform: none; } }
.hero h1, .hero p.lead, .hero-cta, .hero-stats { animation: fadeUp .8s ease both; }
.hero p.lead { animation-delay: .1s; }
.hero-cta { animation-delay: .2s; }
.hero-stats { animation-delay: .3s; }

/* ---------- 响应式 ---------- */
@media (max-width: 980px) {
    .pillars { grid-template-columns: repeat(2, 1fr); }
    .feature-grid { grid-template-columns: repeat(2, 1fr); }
    .steps { grid-template-columns: repeat(2, 1fr); }
    .stat-band { grid-template-columns: repeat(2, 1fr); }
    .footer-grid { grid-template-columns: 1fr 1fr; }
    .contact-cards { grid-template-columns: 1fr; }
}
@media (max-width: 720px) {
    .nav-links {
        position: fixed; top: var(--nav-h); left: 0; right: 0; background: #fff;
        flex-direction: column; align-items: stretch; padding: 14px 20px 22px; gap: 4px;
        box-shadow: 0 14px 30px rgba(15,23,42,.12); transform: translateY(-130%); transition: transform .35s ease;
    }
    .nav-links.open { transform: none; }
    .nav-links a { padding: 13px 14px; }
    .nav-cta { margin: 8px 0 0; }
    .nav-cta .btn { width: 100%; }
    .hamburger { display: flex; }
    .hero { padding: 120px 0 70px; }
    .hero h1 { font-size: 36px; }
    .hero p.lead { font-size: 16px; }
    .hero-stats { gap: 24px; }
    .hero-stats .stat .num { font-size: 30px; }
    .section { padding: 60px 0; }
    .section-head h2 { font-size: 26px; }
    .pillars, .feature-grid, .steps { grid-template-columns: 1fr; }
    .stat-band { grid-template-columns: 1fr 1fr; padding: 30px 18px; }
    .stat-band .num { font-size: 34px; }
    .footer-grid { grid-template-columns: 1fr; }
    .form-wrap { padding: 26px 20px; }
}
@media (prefers-reduced-motion: reduce) {
    .reveal { opacity: 1; transform: none; transition: none; }
    html { scroll-behavior: auto; }
}