/* =============================================================
   设计令牌 + 全局基础样式（新中式黑白素色）
   ============================================================= */

:root {
  --ink-black: #1a1a1a;
  --ink-deep: #444;
  --ink-mid: #777;
  --ink-line: #c9c4bb;
  --ink-line-strong: #8a857c;
  --paper: #f5f1e8;
  --paper-card: rgba(255, 255, 255, .72);
  --line: 1px solid var(--ink-line);
  --font-song: "Source Han Serif SC", "Noto Serif CJK SC", "Noto Serif SC",
               "Songti SC", "STSong", "SimSun", serif;
  --leading: 1.9;
}

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

[hidden] { display: none !important; }

html { -webkit-text-size-adjust: 100%; }

body {
  font-family: var(--font-song);
  color: var(--ink-black);
  background-color: var(--paper);
  background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='140' height='140'%3E%3Cfilter id='n'%3E%3CfeTurbulence type='fractalNoise' baseFrequency='0.9' numOctaves='2' stitchTiles='stitch'/%3E%3C/filter%3E%3Crect width='100%25' height='100%25' filter='url(%23n)' opacity='0.04'/%3E%3C/svg%3E");
  line-height: var(--leading);
  min-height: 100vh;
  display: flex;
  flex-direction: column;
  -webkit-font-smoothing: antialiased;
}

h1, h2, h3, h4 { font-weight: 500; }

a { color: inherit; text-decoration: none; }

button { font-family: inherit; cursor: pointer; }

::selection { background: var(--ink-black); color: var(--paper); }

.empty { text-align: center; color: var(--ink-mid); padding: 2rem; }