/* ============================================================
   pufeng.mygongfu.com — lab 主题（杂志编辑 × 实验记录）
   V1.2 冻结版 · 浅色系（区别于 mygongfu 深色系）
   ============================================================ */
:root {
  color-scheme: light;
  --paper: #FAF7F2;
  --paper-2: #F1ECE3;
  --ink: #2D2A26;
  --ink-2: #5C5750;
  --ink-3: #6E6960;
  --line-1: #DDD6CA;
  --line-2: #C4BCAE;
  --signal: #C0392B;
  --signal-soft: #F3E3E0;
  --font-serif: Georgia, "Noto Serif SC", "Songti SC", serif;
  --font-body: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC", "Microsoft YaHei", sans-serif;
  --font-data: ui-monospace, "SFMono-Regular", Consolas, monospace;
  --page: min(1080px, calc(100vw - 40px));
  --reading: 700px;
  --space-section: clamp(64px, 9vw, 128px);
  --ease: cubic-bezier(.22, 1, .36, 1);
  --z-nav: 30;
}

* { box-sizing: border-box; margin: 0; padding: 0; }
html { scroll-behavior: smooth; }
body {
  background: var(--paper);
  color: var(--ink);
  font-family: var(--font-body);
  font-size: 16px;
  line-height: 1.75;
  -webkit-font-smoothing: antialiased;
}

/* ---------- 布局 ---------- */
.shell { max-width: var(--page); margin: 0 auto; padding: 0 20px; }
.section { padding: var(--space-section) 0; }
.section--tint { background: var(--paper-2); }

/* ---------- 排版 ---------- */
.display {
  font-family: var(--font-serif);
  font-size: clamp(2.2rem, 6vw, 4rem);
  font-weight: 700;
  line-height: 1.15;
  letter-spacing: .01em;
}
.h2 {
  font-family: var(--font-serif);
  font-size: clamp(1.5rem, 3.5vw, 2.2rem);
  font-weight: 700;
  margin-bottom: 16px;
}
.lead { font-size: 1.1rem; color: var(--ink-2); max-width: var(--reading); }
.mono { font-family: var(--font-data); font-size: .85rem; }
.stamp {
  font-family: var(--font-data);
  font-size: .75rem;
  color: var(--ink-3);
  text-transform: uppercase;
  letter-spacing: .12em;
}

/* ---------- Header / Nav ---------- */
.site-header { border-bottom: 1px solid var(--line-1); position: sticky; top: 0; background: var(--paper); z-index: var(--z-nav); }
.site-header__inner { display: flex; align-items: center; justify-content: space-between; max-width: var(--page); margin: 0 auto; padding: 14px 20px; }
.brand { text-decoration: none; color: var(--ink); display: flex; align-items: baseline; gap: 8px; }
.brand__name { font-family: var(--font-serif); font-weight: 700; font-size: 1.1rem; }
.brand__mark { font-family: var(--font-data); font-size: .68rem; color: var(--ink-3); letter-spacing: .1em; }
.site-nav__links { display: flex; gap: 22px; align-items: center; }
.site-nav__links a { text-decoration: none; color: var(--ink-2); font-size: .92rem; }
.site-nav__links a:hover { color: var(--signal); }
.menu-toggle { display: none; background: none; border: none; cursor: pointer; padding: 8px; }
.menu-toggle__line { display: block; width: 20px; height: 2px; background: var(--ink); margin: 4px 0; }

/* ---------- 按钮 ---------- */
.button {
  display: inline-block; padding: 12px 26px;
  border: 1.5px solid var(--ink); border-radius: 0;
  background: transparent; color: var(--ink);
  text-decoration: none; font-size: .95rem; font-weight: 600;
  transition: background var(--ease), color var(--ease);
}
.button:hover { background: var(--ink); color: var(--paper); }
.button--signal { background: var(--signal); border-color: var(--signal); color: #fff; }
.button--signal:hover { background: var(--ink); border-color: var(--ink); color: var(--paper); }

/* ---------- 实验日志卡片 ---------- */
.log-entry { border: 1px solid var(--line-1); padding: 18px 20px; margin-bottom: 12px; background: #fff; }
.log-entry__head { display: flex; justify-content: space-between; align-items: baseline; margin-bottom: 6px; }
.log-entry__id { font-family: var(--font-data); font-size: .75rem; color: var(--signal); font-weight: 700; }
.log-entry__title { font-family: var(--font-serif); font-size: 1.05rem; font-weight: 700; }
.log-entry__note { color: var(--ink-2); font-size: .92rem; }
.log-status { font-family: var(--font-data); font-size: .68rem; padding: 2px 8px; border: 1px solid var(--line-2); }
.log-status--done { color: #1e7d3c; border-color: #1e7d3c; }
.log-status--testing { color: var(--signal); border-color: var(--signal); }
.log-status--idea { color: var(--ink-3); border-color: var(--line-2); }

/* ---------- 三入口卡片 ---------- */
.entry-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 20px; }
.entry-card { border: 1px solid var(--line-1); padding: 26px 24px; text-decoration: none; color: var(--ink); background: #fff; transition: border-color var(--ease), transform var(--ease); }
.entry-card:hover { border-color: var(--signal); transform: translateY(-2px); }
.entry-card__num { font-family: var(--font-data); font-size: .72rem; color: var(--ink-3); letter-spacing: .12em; }
.entry-card__title { font-family: var(--font-serif); font-size: 1.2rem; font-weight: 700; margin: 8px 0 6px; }
.entry-card__desc { color: var(--ink-2); font-size: .88rem; }

/* ---------- 合作模式 ---------- */
.coop-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 20px; }
.coop-card { border: 1px solid var(--line-1); padding: 26px 24px; background: #fff; }
.coop-card__tag { font-family: var(--font-data); font-size: .68rem; color: var(--signal); letter-spacing: .1em; }
.coop-card__title { font-family: var(--font-serif); font-size: 1.15rem; font-weight: 700; margin: 8px 0 8px; }
.coop-card__desc { color: var(--ink-2); font-size: .88rem; margin-bottom: 16px; }

/* ---------- 证明样板（双栏对比） ---------- */
.proof-grid { display: grid; grid-template-columns: 1fr 1fr; gap: 24px; }
.proof-panel { border: 1px solid var(--line-1); padding: 24px; background: #fff; }
.proof-panel__label { font-family: var(--font-data); font-size: .72rem; color: var(--ink-3); letter-spacing: .1em; margin-bottom: 10px; }
.proof-panel ul { list-style: none; }
.proof-panel li { padding: 8px 0; border-bottom: 1px dashed var(--line-1); font-size: .92rem; color: var(--ink-2); }
.proof-panel li strong { color: var(--ink); }

/* ---------- 实验协议表格 ---------- */
.protocol-table { width: 100%; border-collapse: collapse; }
.protocol-table th, .protocol-table td { text-align: left; padding: 12px 14px; border-bottom: 1px solid var(--line-1); font-size: .92rem; vertical-align: top; }
.protocol-table th { font-family: var(--font-data); font-size: .75rem; color: var(--ink-3); letter-spacing: .08em; width: 130px; }
.protocol-table td strong { font-family: var(--font-serif); }

/* ---------- Footer ---------- */
.site-footer { border-top: 1px solid var(--line-1); margin-top: var(--space-section); }
.site-footer__inner { max-width: var(--page); margin: 0 auto; padding: 32px 20px; display: flex; justify-content: space-between; align-items: center; flex-wrap: wrap; gap: 12px; font-size: .85rem; color: var(--ink-2); }
.site-footer a { color: var(--ink-2); text-decoration: none; }
.site-footer a:hover { color: var(--signal); }

/* ---------- 404 ---------- */
.not-found { text-align: center; padding: 120px 20px; }
.not-found__code { font-family: var(--font-data); font-size: 5rem; color: var(--signal); font-weight: 700; }

/* ---------- 响应式 ---------- */
@media (max-width: 900px) {
  .entry-grid, .coop-grid { grid-template-columns: 1fr 1fr; }
}
@media (max-width: 640px) {
  .entry-grid, .coop-grid, .proof-grid { grid-template-columns: 1fr; }
  .menu-toggle { display: block; }
  .site-nav__links { display: none; flex-direction: column; position: absolute; top: 56px; left: 0; right: 0; background: var(--paper); padding: 16px 20px; border-bottom: 1px solid var(--line-1); align-items: flex-start; }
  .site-nav__links.is-open { display: flex; }
}
@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  .entry-card, .button { transition: none; }
}

/* ---------- 键盘可访问性 ---------- */
:focus-visible {
  outline: 2px solid var(--signal);
  outline-offset: 4px;
}