/* ========================================
   公共样式 - 所有页面通用
   ======================================== */

/* ---------- CSS 变量 ---------- */
:root {
    --bg-white: #ffffff;
    --bg-slate-50: #f8fafc;
    --text-slate-900: #0f172a;
    --text-slate-700: #334155;
    --text-slate-600: #475569;
    --text-slate-500: #64748b;
    --text-slate-400: #94a3b8;
    --blue-50: #eff6ff;
    --blue-100: #dbeafe;
    --blue-200: #bfdbfe;
    --blue-300: #93c5fd;
    --blue-400: #60a5fa;
    --blue-500: #3b82f6;
    --blue-600: #2563eb;
    --blue-700: #1d4ed8;
    --blue-800: #1e40af;
    --purple-400: #a78bfa;
    --purple-500: #8b5cf6;
    --purple-600: #7c3aed;
    --emerald-400: #34d399;
    --emerald-500: #10b981;
    --emerald-600: #059669;
    --amber-400: #fbbf24;
    --amber-500: #f59e0b;
    --amber-600: #d97706;
    --rose-400: #fb7185;
    --rose-500: #f43f5e;
    --cyan-400: #22d3ee;
    --cyan-500: #06b6d4;
    --indigo-400: #818cf8;
    --indigo-500: #6366f1;
    --shadow-sm: 0 1px 2px rgba(0,0,0,0.04);
    --shadow-md: 0 4px 6px -1px rgba(0,0,0,0.06);
    --shadow-lg: 0 10px 25px -3px rgba(0,0,0,0.07);
    --shadow-xl: 0 20px 40px -8px rgba(0,0,0,0.09);
    --radius-sm: 8px;
    --radius-md: 12px;
    --radius-lg: 18px;
    --radius-xl: 24px;
    --radius-2xl: 32px;
    --radius-full: 999px;
    --transition: 0.25s cubic-bezier(0.4,0,0.2,1);
    --font-sans: 'Inter', 'PingFang SC', 'Microsoft YaHei', system-ui, sans-serif;
}

/* ---------- Reset & Base ---------- */
* { margin: 0; padding: 0; box-sizing: border-box; }
html { scroll-behavior: smooth; -webkit-font-smoothing: antialiased; }
body {
    font-family: var(--font-sans);
    background: var(--bg-white);
    color: var(--text-slate-900);
    line-height: 1.6;
    overflow-x: hidden;
}

/* ---------- 点阵背景 ---------- */
.dot-bg {
    position: fixed; top: 0; left: 0; width: 100%; height: 100%;
    pointer-events: none; z-index: 0;
    background-image: radial-gradient(circle, #bfdbfe 1px, transparent 1px);
    background-size: 28px 28px; opacity: 0.32;
    mask-image: radial-gradient(ellipse 70% 60% at 50% 40%, black 25%, transparent 70%);
    -webkit-mask-image: radial-gradient(ellipse 70% 60% at 50% 40%, black 25%, transparent 70%);
}

/* ---------- 柔和光晕 ---------- */
.soft-glow {
    position: fixed; border-radius: 50%; filter: blur(140px);
    pointer-events: none; z-index: 0; opacity: 0.08;
}

/* ---------- 导航栏 ---------- */
.navbar {
    position: sticky; top: 0; z-index: 100;
    background: rgba(255,255,255,0.82); backdrop-filter: blur(18px);
    -webkit-backdrop-filter: blur(18px);
    border-bottom: 1px solid rgba(226,232,240,0.6);
    height: 62px; display: flex; align-items: center;
    justify-content: space-between; padding: 0 24px;
}
.nav-brand {
    display: flex; align-items: center; gap: 10px;
    text-decoration: none; color: var(--text-slate-900);
    font-weight: 700; font-size: 1.35rem;
}
.nav-logo {
    width: 36px; height: 36px;
    background: linear-gradient(135deg, #2563eb, #1e40af);
    border-radius: var(--radius-sm);
    display: flex; align-items: center; justify-content: center;
    color: #fff; font-weight: 800;
}
.nav-links { display: flex; align-items: center; gap: 6px; list-style: none; }
.nav-links a {
    text-decoration: none; color: var(--text-slate-700);
    font-size: 0.9rem; font-weight: 500; padding: 8px 14px;
    border-radius: var(--radius-full); transition: var(--transition);
}
.nav-links a:hover { background: var(--blue-50); color: var(--blue-600); }
.nav-links a.active-nav {
    background: var(--blue-50); color: var(--blue-600); font-weight: 600;
}
.nav-cta {
    background: var(--blue-600) !important; color: #fff !important;
    font-weight: 600 !important; padding: 9px 20px !important;
    box-shadow: 0 2px 8px rgba(37,99,235,0.3);
}
.mobile-menu-btn {
    display: none; background: none; border: none; cursor: pointer;
    padding: 8px; color: var(--text-slate-700);
}
.mobile-menu-btn svg { width: 22px; height: 22px; stroke: currentColor; }

/* ---------- 按钮 ---------- */
.btn {
    display: inline-flex; align-items: center; gap: 6px;
    padding: 14px 28px; border-radius: var(--radius-full);
    font-weight: 600; font-size: 0.95rem; text-decoration: none;
    transition: var(--transition); cursor: pointer; border: none;
}
.btn-primary { background: var(--blue-600); color: #fff; box-shadow: 0 8px 24px rgba(37,99,235,0.3); }
.btn-primary:hover { background: var(--blue-700); transform: translateY(-2px); }
.btn-outline { background: transparent; color: var(--blue-700); border: 1.5px solid var(--blue-300); }
.btn-outline:hover { background: var(--blue-50); border-color: var(--blue-400); }

/* ---------- 标题 ---------- */
.section-title {
    text-align: center; font-size: 1.8rem; font-weight: 700;
    letter-spacing: -0.5px; margin-bottom: 8px; color: var(--text-slate-900);
}
.section-sub {
    text-align: center; color: var(--text-slate-500); font-size: 0.95rem;
}

/* ---------- 图标背景色 ---------- */
.bg-blue-light { background: #eff6ff; color: #2563eb; }
.bg-purple-light { background: #f5f3ff; color: #7c3aed; }
.bg-emerald-light { background: #ecfdf5; color: #10b981; }
.bg-amber-light { background: #fffbeb; color: #d97706; }
.bg-cyan-light { background: #ecfeff; color: #06b6d4; }
.bg-rose-light { background: #ffe4e6; color: #f43f5e; }
.bg-indigo-light { background: #eef2ff; color: #6366f1; }
.bg-teal-light { background: #f0fdfa; color: #14b8a6; }

/* ---------- 页脚 ---------- */
.footer {
    border-top: 1px solid #e8ecf1; background: var(--bg-slate-50);
    padding: 20px 24px; position: relative; z-index: 1;
}
.footer-inner {
    max-width: 1200px; margin: 0 auto; display: flex;
    align-items: center; justify-content: space-between;
    flex-wrap: wrap; gap: 12px;
}
.footer-left { display: flex; align-items: center; flex-wrap: wrap; gap: 16px; }
.footer-copyright { font-size: 0.85rem; color: var(--text-slate-500); white-space: nowrap; }
.footer-links { display: flex; flex-wrap: wrap; gap: 14px; }
.footer-links a { font-size: 0.85rem; color: var(--blue-600); text-decoration: none; font-weight: 500; white-space: nowrap; }
.footer-links a:hover { text-decoration: underline; }
.footer-right { display: flex; align-items: center; gap: 8px; font-size: 0.85rem; color: var(--text-slate-700); white-space: nowrap; }
.footer-right a { color: var(--blue-600); text-decoration: none; font-weight: 600; }
.beian-link { font-size: 0.85rem; color: var(--text-slate-500); text-decoration: none; white-space: nowrap; }
.beian-link:hover { text-decoration: underline; }

/* ---------- 响应式：移动端导航 ---------- */
@media (max-width: 768px) {
    .nav-links {
        display: none; position: fixed; top: 62px; left: 0; right: 0;
        background: rgba(255,255,255,0.97); backdrop-filter: blur(20px);
        flex-direction: column; padding: 16px;
        border-bottom: 1px solid #e2e8f0; z-index: 99;
    }
    .nav-links.mobile-open { display: flex; }
    .mobile-menu-btn { display: block; }
    .footer-inner { flex-direction: column; align-items: flex-start; }
}