/* 物种繁衍论 · 静态站 —— 深蓝星空金色体系 */
:root {
  --bg0: #0d152b; --bg1: #1b2a4f; --panel: rgba(20, 32, 60, .72);
  --line: rgba(212, 175, 55, .35); --gold: #d4af37; --gold-l: #e8c96a;
  --txt: #dfe6f3; --dim: #8f9ab5;
}
* { box-sizing: border-box; margin: 0; padding: 0; }
body {
  font-family: "Microsoft YaHei", "PingFang SC", sans-serif;
  color: var(--txt);
  background: linear-gradient(180deg, var(--bg0), var(--bg1) 60%, var(--bg0));
  min-height: 100vh;
  line-height: 1.85;
}
a { color: var(--gold-l); text-decoration: none; }
a:hover { text-decoration: underline; }

/* 全局侧栏布局（可折叠目录） */
.main { margin-left: 264px; min-height: 100vh; }
body.nosb .main { margin-left: 0; }

/* 首页 hero */
.hero { text-align: center; padding: 88px 20px 40px; position: relative; overflow: hidden; }
.hero .stars {
  position: absolute; inset: 0; pointer-events: none; opacity: .5;
  background-image: radial-gradient(1.5px 1.5px at 12% 22%, #fff, transparent),
    radial-gradient(1px 1px at 70% 12%, #cfd8ff, transparent),
    radial-gradient(2px 2px at 86% 40%, #fff, transparent),
    radial-gradient(1px 1px at 30% 70%, #ffe9b0, transparent),
    radial-gradient(1.5px 1.5px at 55% 55%, #fff, transparent),
    radial-gradient(1px 1px at 42% 12%, #fff, transparent);
}
.hero h1 { font-size: 64px; letter-spacing: 18px; color: var(--gold-l);
  text-shadow: 0 0 34px rgba(212, 175, 55, .45); position: relative; }
.hero .author { color: var(--dim); margin: 10px 0 18px; letter-spacing: 6px; }
.hero .motto { color: var(--txt); font-size: 15px; line-height: 2.1; }
.hero .slogan { margin-top: 26px; display: inline-block; padding: 10px 26px;
  border: 1px solid var(--line); border-radius: 999px; color: var(--gold-l);
  background: rgba(212, 175, 55, .08); position: relative; }

.stats { display: flex; justify-content: center; gap: 26px; flex-wrap: wrap;
  padding: 18px; color: var(--dim); font-size: 14px; }
.stats b { color: var(--gold-l); font-size: 20px; margin-right: 4px; }

.reader-entry { display: block; max-width: 720px; margin: 26px auto 8px; padding: 22px 30px;
  border: 1px solid var(--line); border-radius: 14px; background: var(--panel);
  text-align: center; transition: box-shadow .2s; }
.reader-entry:hover { text-decoration: none; box-shadow: 0 0 26px rgba(212, 175, 55, .25); }
.reader-entry b { display: block; font-size: 21px; color: var(--gold-l); margin-bottom: 6px; }
.reader-entry span { color: var(--dim); font-size: 14px; }

/* 篇章卡片 */
.parts { max-width: 1060px; margin: 20px auto 60px; padding: 0 18px; }
.part-card { border: 1px solid var(--line); border-radius: 14px;
  background: var(--panel); margin: 22px 0; overflow: hidden; }
.part-card h2 { padding: 14px 22px; border-bottom: 1px solid var(--line);
  font-size: 19px; color: var(--txt); }
.part-card h2 i { font-style: normal; color: var(--gold-l); margin-right: 12px; }
.part-card h2 em { font-style: normal; float: right; color: var(--dim); font-size: 14px; }
.part-card ul { list-style: none; display: grid;
  grid-template-columns: repeat(auto-fill, minmax(300px, 1fr)); gap: 1px;
  background: rgba(212, 175, 55, .12); }
.part-card li { background: #101c38; }
.part-card li a { display: flex; gap: 10px; align-items: baseline; padding: 12px 18px;
  color: var(--txt); }
.part-card li a:hover { text-decoration: none; background: rgba(212, 175, 55, .08); }
.part-card li b { color: var(--gold-l); white-space: nowrap; }
.part-card li small { color: var(--dim); margin-left: auto; font-size: 12px; }
footer { text-align: center; color: var(--dim); padding: 30px 10px 40px; font-size: 13px; }

/* 全局侧栏（可折叠目录） */
.sidebar { position: fixed; left: 0; top: 0; bottom: 0; width: 264px; z-index: 60;
  background: rgba(9, 15, 32, .97); border-right: 1px solid var(--line);
  display: flex; flex-direction: column; transition: transform .25s; }
body.nosb .sidebar { transform: translateX(-100%); }
.sb-head { display: flex; align-items: center; gap: 8px; padding: 14px 10px 14px 16px;
  border-bottom: 1px solid var(--line); }
.sb-head a { flex: 1; }
.sb-head b { display: block; color: var(--gold-l); font-size: 19px; letter-spacing: 5px; }
.sb-head span { display: block; color: var(--dim); font-size: 11px; margin-top: 2px; }
.sb-close { background: none; border: 1px solid var(--line); color: var(--gold-l);
  border-radius: 8px; width: 30px; height: 30px; cursor: pointer; font-size: 15px; }
.sb-close:hover { background: rgba(212, 175, 55, .12); }
.sb-nav { flex: 1; overflow-y: auto; padding: 8px 10px; scrollbar-width: thin; }
.sb-nav details { margin: 2px 0; }
.sb-nav summary { display: flex; align-items: baseline; gap: 8px; cursor: pointer;
  padding: 8px 10px; border-radius: 8px; color: var(--gold-l); font-size: 14px; list-style: none; }
.sb-nav summary::-webkit-details-marker { display: none; }
.sb-nav summary::before { content: '▸'; color: var(--dim); font-size: 11px; transition: transform .2s; }
.sb-nav details[open] summary::before { transform: rotate(90deg); }
.sb-nav summary span { color: var(--dim); font-size: 11px; flex: 1; }
.sb-nav summary em { font-style: normal; color: var(--dim); font-size: 11px; }
.sb-nav ul { list-style: none; padding: 2px 4px 8px; }
.sb-nav li a { display: flex; align-items: baseline; gap: 8px; padding: 5px 10px;
  color: var(--txt); font-size: 13px; border-radius: 6px; }
.sb-nav li a:hover { background: rgba(212, 175, 55, .12); text-decoration: none; }
.sb-nav li a.cur { background: rgba(212, 175, 55, .18); color: var(--gold-l); }
.sb-nav li a i { font-style: normal; color: var(--dim); font-size: 11px; min-width: 20px; }
.sb-nav li a span { overflow: hidden; text-overflow: ellipsis; white-space: nowrap; }
.sb-nav li.grp { margin: 1px 0; }
.sb-nav li.grp > details > summary { padding: 5px 8px 5px 20px; border-radius: 6px; }
.sb-nav li.grp > details > summary a { flex: 1; display: flex; align-items: baseline; gap: 6px;
  color: var(--txt); font-size: 13px; }
.sb-nav li.grp > details > summary a:hover { color: var(--gold-l); text-decoration: none; }
.sb-nav li.grp > details > summary a em { font-style: normal; color: var(--dim);
  font-size: 11px; margin-left: auto; }
.sb-nav li.grp > details[open] > summary a { color: var(--gold-l); }
.sb-nav li.grp ul { padding: 1px 0 4px 10px; }
.sb-nav li.grp ul li a { padding: 4px 8px; font-size: 12.5px; }
.sb-nav li.grp ul li a i { min-width: 18px; font-size: 10.5px; }
.sb-foot { padding: 10px; border-top: 1px solid var(--line); }
.sb-foot a { display: block; text-align: center; padding: 10px; border: 1px solid var(--line);
  border-radius: 10px; background: rgba(212, 175, 55, .06); }
.sb-foot a.cur { background: rgba(212, 175, 55, .18); }
.sb-fab { display: none; position: fixed; left: 14px; top: 14px; z-index: 55;
  padding: 9px 16px; border: 1px solid var(--line); border-radius: 999px;
  background: rgba(9, 15, 32, .92); color: var(--gold-l); font-size: 14px; cursor: pointer; }
body.nosb .sb-fab { display: block; }
body.nosb .sb-fab::before { content: ''; }

@media (max-width: 900px) {  /* 移动端：侧栏抽屉化，加遮罩 */
  .main { margin-left: 0; }
  .sidebar { box-shadow: 18px 0 60px rgba(0, 0, 0, .5); }
  .sb-fab { display: block; }
  .hero h1 { font-size: 42px; letter-spacing: 10px; }
  .chnav { flex-direction: column; gap: 10px; }
  .chnav a { max-width: 100%; text-align: center; }
}

/* 阅读页（正文单栏，导航由全局侧栏承担） */
.page-head { position: sticky; top: 0; z-index: 20; display: flex; gap: 18px;
  align-items: center; padding: 12px 20px; background: rgba(13, 21, 43, .92);
  border-bottom: 1px solid var(--line); backdrop-filter: blur(6px); }
.page-head .back { color: var(--gold-l); }
.page-head b { font-size: 17px; }
.page-head span { color: var(--dim); font-size: 13px; }
.reader-art { max-width: 800px; margin: 0 auto; padding: 30px 20px 90px; }
.reader-art section { margin: 30px 0; }
.reader-art h1 { font-size: 30px; color: var(--gold-l); margin-bottom: 14px; }
.reader-art h2 { font-size: 23px; color: var(--gold-l); margin: 34px 0 12px;
  padding-top: 18px; border-top: 1px solid var(--line); }
.reader-art h3 { font-size: 19px; color: var(--txt); margin: 24px 0 10px; }
.reader-art p { margin: 10px 0; text-indent: 2em; }

/* 章节页 */
.chapter { max-width: 1080px; margin: 0 auto; padding: 30px 18px 70px; }
.chapter h1 { font-size: 30px; color: var(--gold-l); text-align: center; margin-top: 12px; }
.chapter .meta { text-align: center; color: var(--dim); font-size: 13px; margin: 10px 0 18px; }
.secnav { display: flex; justify-content: center; gap: 14px; margin: 14px 0 26px; }
.secnav a { padding: 7px 18px; border: 1px solid var(--line); border-radius: 999px;
  background: var(--panel); font-size: 14px; }
.secnav a:hover { text-decoration: none; background: rgba(212, 175, 55, .12); }

/* 顶部显示开关（思维导图 / 正文 / PPT） */
.toggles { display: flex; justify-content: center; align-items: center; gap: 10px;
  margin: 14px 0 26px; }
.toggles > span { color: var(--dim); font-size: 13px; letter-spacing: 2px; }
.tgg { padding: 7px 20px; border: 1px solid var(--line); border-radius: 999px;
  background: rgba(212, 175, 55, .1); color: var(--gold-l); font-size: 14px;
  cursor: pointer; transition: background .15s, opacity .15s; font-family: inherit; }
.tgg:hover { background: rgba(212, 175, 55, .22); }
.tgg.off { opacity: .4; color: var(--dim); border-style: dashed;
  background: var(--panel); text-decoration: line-through; }
body.hide-mm #mm { display: none; }
body.hide-art .prose h3, body.hide-art .prose p { display: none; }
body.hide-sl .prose figure.fig-sl { display: none; }
.block { margin: 34px 0; }
.block h2 { font-size: 21px; color: var(--gold-l); border-left: 4px solid var(--gold);
  padding-left: 12px; margin-bottom: 16px; }
.block figure { margin: 14px auto; text-align: center; }
.block img { max-width: 100%; border-radius: 10px; border: 1px solid var(--line);
  cursor: zoom-in; box-shadow: 0 8px 30px rgba(0, 0, 0, .45); }
.block figcaption { color: var(--dim); font-size: 13px; margin-top: 8px; }
.empty { color: var(--dim); text-align: center; padding: 30px; }
.block h2 small { color: var(--dim); font-size: 13px; font-weight: normal; margin-left: 10px; }

/* 正文（精华版段落 + 穿插 PPT 图） */
.prose { max-width: 860px; margin: 0 auto; background: var(--panel);
  border: 1px solid var(--line); border-radius: 14px; padding: 30px 38px 26px; }
.prose h3 { font-size: 18px; color: var(--gold-l); margin: 26px 0 10px; }
.prose p { margin: 12px 0; text-indent: 2em; line-height: 2.05; }
.prose figure { margin: 30px auto 32px; text-align: center; }
.prose figure img { max-width: 100%; border-radius: 10px; border: 1px solid var(--line);
  cursor: zoom-in; box-shadow: 0 8px 30px rgba(0, 0, 0, .45); }
.prose figcaption { color: var(--dim); font-size: 12px; margin-top: 8px; }
.prose figcaption i { font-style: normal; color: var(--gold-l); border: 1px solid var(--line);
  border-radius: 4px; padding: 1px 6px; margin-right: 8px; font-size: 11px; }

@media (max-width: 700px) { .prose { padding: 20px 16px; } }
.chnav { display: flex; justify-content: space-between; margin-top: 44px;
  padding-top: 20px; border-top: 1px solid var(--line); }
.chnav a { padding: 10px 18px; border: 1px solid var(--line); border-radius: 10px;
  background: var(--panel); font-size: 14px; max-width: 46%; }
.chnav a:hover { text-decoration: none; background: rgba(212, 175, 55, .12); }

/* 灯箱 */
.lightbox { position: fixed; inset: 0; background: rgba(5, 9, 20, .93); z-index: 99;
  display: none; align-items: center; justify-content: center; }
.lightbox.on { display: flex; }
.lightbox img { max-width: 96vw; max-height: 94vh; border-radius: 8px; }
.lightbox button { position: absolute; background: none; color: var(--gold-l);
  border: 1px solid var(--line); border-radius: 8px; font-size: 26px;
  width: 52px; height: 52px; cursor: pointer; }
.lightbox .lb-close { top: 18px; right: 18px; }
.lightbox .lb-prev { left: 18px; top: 50%; transform: translateY(-50%); }
.lightbox .lb-next { right: 18px; top: 50%; transform: translateY(-50%); }

/* ── 访问统计与读者留言（由 js/srt-api.js 动态渲染）──────── */
.srt-meta { max-width: 860px; margin: 0 auto; padding: 16px 20px 10px; text-align: center;
  color: var(--dim); font-size: 12.5px; letter-spacing: .5px; }
.srt-meta span { margin: 0 9px; white-space: nowrap; }
.srt-meta b { color: var(--gold-l); font-weight: normal; font-size: 14px; margin: 0 3px; }
.srt-cm { max-width: 860px; margin: 8px auto 70px; padding: 0 20px; }
.srt-cm .srt-hd { font-size: 20px; color: var(--gold-l); border-left: 4px solid var(--gold);
  padding-left: 12px; margin-bottom: 6px; }
.srt-cm .srt-hd small { color: var(--dim); font-size: 12px; font-weight: normal; margin-left: 8px; }
.srt-cm .srt-tip { color: var(--dim); font-size: 12.5px; margin: 0 0 14px 16px; }
.srt-cm form { border: 1px solid var(--line); border-radius: 14px; background: var(--panel);
  padding: 16px 18px; margin-bottom: 22px; }
.srt-cm .srt-row { display: flex; gap: 10px; align-items: center; flex-wrap: wrap; }
.srt-cm .srt-row input { max-width: 240px; }
.srt-cm input, .srt-cm textarea { background: rgba(9, 15, 32, .7); color: var(--txt);
  border: 1px solid var(--line); border-radius: 10px; padding: 9px 12px; font: inherit;
  font-size: 14px; outline: none; transition: border-color .15s; }
.srt-cm input { flex: 1; min-width: 150px; }
.srt-cm input:focus, .srt-cm textarea:focus { border-color: var(--gold); }
.srt-cm textarea { width: 100%; margin: 10px 0; min-height: 92px; resize: vertical;
  line-height: 1.8; }
.srt-cm button { padding: 7px 22px; border: 1px solid var(--line); border-radius: 999px;
  background: rgba(212, 175, 55, .12); color: var(--gold-l); font: inherit; font-size: 14px;
  cursor: pointer; }
.srt-cm button:hover:not(:disabled) { background: rgba(212, 175, 55, .24); }
.srt-cm button:disabled { opacity: .5; cursor: default; }
.srt-cm .srt-hp { position: absolute; left: -9999px; width: 1px; height: 1px;
  opacity: 0; pointer-events: none; }
.srt-cm .srt-msg { font-size: 13px; color: var(--dim); margin-left: 12px; }
.srt-cm .srt-msg.bad { color: #e8a0a0; }
.srt-cm .srt-msg.good { color: var(--gold-l); }
.srt-cm-list { list-style: none; }
.srt-cm-list li { border: 1px solid var(--line); border-radius: 12px; background: var(--panel);
  padding: 13px 18px; margin-bottom: 11px; }
.srt-cm-list .hd { display: flex; gap: 12px; align-items: baseline; margin-bottom: 5px; }
.srt-cm-list .hd b { color: var(--gold-l); font-weight: normal; }
.srt-cm-list .hd time { color: var(--dim); font-size: 12px; margin-left: auto; }
.srt-cm-list .tx { white-space: pre-wrap; word-break: break-word; font-size: 14.5px; }
.srt-cm-list .rp { margin-top: 10px; padding: 9px 13px; border-left: 3px solid var(--gold);
  background: rgba(212, 175, 55, .07); border-radius: 0 8px 8px 0; font-size: 14px;
  white-space: pre-wrap; word-break: break-word; }
.srt-cm-list .rp i { font-style: normal; display: block; color: var(--gold-l);
  font-size: 12px; margin-bottom: 3px; }
.srt-empty { color: var(--dim); font-size: 14px; text-align: center; padding: 16px; }
.srt-more { display: block; margin: 4px auto 0; }