/* ============================================================
   锦渚浮桥 · 设计系统 tokens.css
   水韵蓝 × 工程质感 —— 基础层：设计令牌 / 重置 / 排版 / 布局
   ============================================================ */

/* ---------- Design Tokens ---------- */
:root {
  /* Brand colors */
  --brand-50: #eef7fb;
  --brand-100: #d8ecf6;
  --brand-200: #b0d9ec;
  --brand-300: #7fc0dd;
  --brand-400: #4aa3c9;
  --brand-500: #1f86b4;
  --brand-600: #0b6fa6;      /* primary */
  --brand-700: #0a5c8a;
  --brand-800: #0a4a6f;
  --brand-900: #083d5c;      /* deep navy */
  --brand-950: #062d45;

  /* Accent */
  --accent-400: #f0b45e;
  --accent-500: #e8a33d;     /* gold */
  --accent-600: #d18a22;

  /* Neutrals */
  --ink-900: #12242f;        /* heading */
  --ink-700: #2a3b47;        /* body */
  --ink-500: #5c6b78;        /* secondary */
  --ink-400: #8b98a3;        /* muted */
  --line: #e2eaf0;           /* borders */
  --bg: #ffffff;
  --bg-soft: #f4f8fb;        /* soft section */
  --bg-deep: #083d5c;        /* dark section */

  /* Gradients */
  --grad-brand: linear-gradient(135deg, #0b6fa6 0%, #0a4a6f 100%);
  --grad-hero: linear-gradient(120deg, rgba(6,45,69,.92) 0%, rgba(10,74,111,.78) 55%, rgba(31,134,180,.55) 100%);
  --grad-gold: linear-gradient(135deg, #f0b45e 0%, #d18a22 100%);

  /* Typography */
  --font-sans: "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", "Noto Sans SC", "Source Han Sans SC", sans-serif;
  --font-num: "DIN Alternate", "Bahnschrift", "Arial Narrow", var(--font-sans);

  /* Layout */
  --container: 1200px;
  --radius: 10px;
  --radius-lg: 16px;
  --shadow-sm: 0 2px 8px rgba(8, 61, 92, .06);
  --shadow-md: 0 6px 24px rgba(8, 61, 92, .10);
  --shadow-lg: 0 16px 48px rgba(8, 61, 92, .16);
  --transition: .28s cubic-bezier(.4, 0, .2, 1);
}

/* ---------- Reset & Base ---------- */
*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }
html { scroll-behavior: smooth; -webkit-text-size-adjust: 100%; }
body {
  font-family: var(--font-sans);
  font-size: 16px;
  line-height: 1.7;
  color: var(--ink-700);
  background: var(--bg);
  -webkit-font-smoothing: antialiased;
}
img { display: block; max-width: 100%; height: auto; }
a { color: inherit; text-decoration: none; transition: color var(--transition); }
ul, ol { list-style: none; }
button { font-family: inherit; cursor: pointer; border: none; background: none; }
input, textarea, select { font-family: inherit; font-size: 1rem; }
::selection { background: var(--brand-600); color: #fff; }

/* ---------- Layout helpers ---------- */
.container { width: 100%; max-width: var(--container); margin: 0 auto; padding: 0 24px; }
.section { padding: 88px 0; }
.section--soft { background: var(--bg-soft); }
.section--deep { background: var(--bg-deep); color: #dbe9f2; }
.section--compact { padding: 56px 0; }

/* ---------- Typography ---------- */
h1, h2, h3, h4, h5 { color: var(--ink-900); line-height: 1.3; font-weight: 700; }
h1 { font-size: clamp(1.9rem, 4vw, 3rem); }
h2 { font-size: clamp(1.6rem, 3vw, 2.3rem); }
h3 { font-size: clamp(1.2rem, 2vw, 1.5rem); }
.section--deep h1, .section--deep h2, .section--deep h3 { color: #fff; }

/* Section header */
.section-head { text-align: center; max-width: 760px; margin: 0 auto 56px; }
.section-head__tag {
  display: inline-flex; align-items: center; gap: 8px;
  font-size: .85rem; font-weight: 600; letter-spacing: .14em;
  color: var(--brand-600); text-transform: uppercase;
}
.section-head__tag::before, .section-head__tag::after {
  content: ""; width: 26px; height: 1px; background: var(--brand-400);
}
.section-head h2 { margin: 12px 0 14px; }
.section-head p { color: var(--ink-500); font-size: 1.02rem; }
.section-head--left { text-align: left; margin: 0 0 40px; }
.section-head--left .section-head__tag::before { display: none; }
.section--deep .section-head__tag { color: var(--accent-400); }
.section--deep .section-head p { color: #b8cbd8; }