/* ============================================================
   Overbooked 学习笔记 — PE/VC & Scaling Operator Pivot
   Shared stylesheet. Brand: coral #FF4F47 + ink #151515.
   Mobile + desktop friendly.
   ============================================================ */

:root{
  --coral:#FF4F47;
  --coral-soft:#fff2f1;
  --ink:#151515;
  --ink-2:#333;
  --body:#4a4a4a;
  --muted:#777;
  --line:#e7e7e7;
  --bg:#eef0f2;
  --card:#f6f7f8;
  --green:#1a7a4a;
  --green-soft:#e4f6ec;
  --amber:#a86400;
  --amber-soft:#fbf1dd;
  --maxw:880px;
}

*{box-sizing:border-box;}
html{-webkit-text-size-adjust:100%;}
body{
  margin:0;
  background:var(--bg);
  color:var(--body);
  font-family:'Inter',-apple-system,BlinkMacSystemFont,'Segoe UI','PingFang SC','Microsoft YaHei',sans-serif;
  font-size:16px;
  line-height:1.7;
  -webkit-font-smoothing:antialiased;
}

.page{
  max-width:var(--maxw);
  margin:24px auto;
  background:#fff;
  padding:44px 52px 60px;
  box-shadow:0 6px 30px rgba(0,0,0,.10);
  border-radius:6px;
}

/* ---------- Header / Footer ---------- */
.site-head{
  display:flex;align-items:center;justify-content:space-between;
  gap:12px;
  border-bottom:2px solid var(--ink);
  padding-bottom:14px;margin-bottom:8px;
}
.brand{display:flex;align-items:center;gap:9px;text-decoration:none;}
.brand svg{display:block;height:30px;width:30px;flex:none;}
.brand .wm{
  font-family:'Montserrat',sans-serif;font-weight:800;
  font-size:19px;color:var(--ink);letter-spacing:-.01em;
}
.head-meta{font-size:11px;font-weight:700;letter-spacing:.12em;text-transform:uppercase;color:var(--muted);text-align:right;}

.site-foot{
  margin-top:54px;padding-top:20px;border-top:1px solid var(--line);
  display:flex;flex-direction:column;align-items:center;gap:8px;
  color:var(--muted);font-size:12px;text-align:center;
}
.site-foot svg{height:26px;width:26px;}

/* ---------- Typographic scale ---------- */
h1.title{
  font-family:'Montserrat',sans-serif;font-weight:800;
  font-size:34px;line-height:1.18;color:var(--ink);
  margin:26px 0 10px;letter-spacing:-.02em;
}
.subtitle{font-size:17px;color:var(--ink-2);margin:0 0 8px;font-weight:600;}
.oneliner{font-size:15px;color:var(--body);margin:0 0 4px;}

h2{
  font-family:'Montserrat',sans-serif;font-weight:800;
  font-size:24px;line-height:1.25;color:var(--ink);
  margin:46px 0 6px;letter-spacing:-.01em;
  padding-top:8px;
}
h2 .dnum{color:var(--coral);}
h3{
  font-family:'Montserrat',sans-serif;font-weight:700;
  font-size:18px;color:var(--ink);margin:28px 0 8px;
}
h4{font-weight:800;font-size:15px;color:var(--ink);margin:18px 0 6px;}
p{margin:10px 0;}
strong{color:var(--ink);font-weight:700;}
a{color:var(--coral);}

.section-title{
  font-size:11px;font-weight:800;letter-spacing:.14em;text-transform:uppercase;
  color:var(--coral);margin:40px 0 4px;
}
.lead{font-size:16px;color:var(--ink-2);}

/* ---------- Boxes / Cards ---------- */
.hl{
  border-left:4px solid var(--coral);background:var(--coral-soft);
  padding:14px 18px;border-radius:0 8px 8px 0;margin:16px 0;
}
.hl.dark{background:var(--ink);color:#f4f4f4;border-left-color:var(--coral);}
.hl.dark strong{color:#fff;}
.hl.green{border-left-color:var(--green);background:var(--green-soft);}
.hl.amber{border-left-color:var(--amber);background:var(--amber-soft);}
.hl .k{display:block;font-size:10px;font-weight:800;letter-spacing:.12em;text-transform:uppercase;color:var(--coral);margin-bottom:4px;}
.hl.dark .k{color:var(--coral);}

.card{background:var(--card);border-radius:10px;padding:16px 18px;border:1px solid var(--line);}
.card .card-label{font-size:10px;font-weight:800;letter-spacing:.1em;text-transform:uppercase;color:var(--coral);display:block;margin-bottom:6px;}

.grid2{display:grid;grid-template-columns:1fr 1fr;gap:14px;margin:16px 0;}
.grid3{display:grid;grid-template-columns:1fr 1fr 1fr;gap:14px;margin:16px 0;}

/* ---------- Key takeaways ---------- */
.takeaways{list-style:none;padding:0;margin:16px 0;counter-reset:tk;}
.takeaways li{
  position:relative;padding:12px 14px 12px 52px;margin:10px 0;
  background:var(--card);border-radius:10px;border:1px solid var(--line);font-size:15px;
}
.takeaways li::before{
  counter-increment:tk;content:counter(tk);
  position:absolute;left:12px;top:12px;width:28px;height:28px;border-radius:50%;
  background:var(--coral);color:#fff;font-weight:800;font-size:14px;
  display:flex;align-items:center;justify-content:center;
}

/* ---------- SOP / steps ---------- */
.steps{margin:16px 0;}
.step{display:flex;gap:14px;align-items:flex-start;padding:12px 0;border-bottom:1px dashed var(--line);}
.step:last-child{border-bottom:none;}
.step .n{
  flex:none;width:32px;height:32px;border-radius:50%;background:var(--ink);color:#fff;
  font-weight:800;font-size:15px;display:flex;align-items:center;justify-content:center;
}
.step .n.coral{background:var(--coral);}
.step .b{flex:1;}
.step .b .t{font-weight:800;color:var(--ink);font-size:15px;}

/* ---------- Tables ---------- */
.tw{overflow-x:auto;-webkit-overflow-scrolling:touch;margin:16px 0;border-radius:8px;border:1px solid var(--line);}
table{border-collapse:collapse;width:100%;min-width:520px;font-size:14px;}
thead th{background:var(--ink);color:#fff;text-align:left;padding:10px 12px;font-weight:700;font-size:13px;}
tbody td{padding:10px 12px;border-top:1px solid var(--line);vertical-align:top;}
tbody tr:nth-child(even){background:#fafafa;}
td .yes{color:var(--green);font-weight:800;}
td .no{color:var(--coral);font-weight:800;}
td .mid{color:var(--amber);font-weight:800;}

/* ---------- Badges ---------- */
.badge{display:inline-block;padding:2px 9px;border-radius:999px;font-size:11px;font-weight:800;letter-spacing:.02em;}
.badge.red{background:var(--coral-soft);color:var(--coral);}
.badge.green{background:var(--green-soft);color:var(--green);}
.badge.amber{background:var(--amber-soft);color:var(--amber);}
.badge.ink{background:#eee;color:var(--ink);}

/* ---------- Hub nav grid ---------- */
.navgrid{display:grid;grid-template-columns:1fr 1fr;gap:14px;margin:22px 0;}
.navcard{
  display:block;text-decoration:none;color:inherit;background:#fff;border:1.5px solid var(--line);
  border-radius:12px;padding:18px 18px 16px;transition:.15s;
}
.navcard:hover{border-color:var(--coral);box-shadow:0 6px 20px rgba(255,79,71,.12);transform:translateY(-2px);}
.navcard .idx{font-family:'Montserrat',sans-serif;font-weight:800;font-size:13px;color:var(--coral);}
.navcard .nt{font-family:'Montserrat',sans-serif;font-weight:800;font-size:17px;color:var(--ink);margin:4px 0 6px;}
.navcard .nd{font-size:13px;color:var(--muted);line-height:1.55;}
.navcard.star{border-color:var(--coral);background:linear-gradient(180deg,#fff,var(--coral-soft));}
.navcard .star-tag{display:inline-block;font-size:10px;font-weight:800;letter-spacing:.08em;text-transform:uppercase;color:#fff;background:var(--coral);padding:2px 8px;border-radius:999px;margin-left:6px;vertical-align:middle;}

/* ---------- Page-to-page nav ---------- */
.crumb{margin:0 0 4px;}
.crumb a{font-size:12px;font-weight:700;color:var(--muted);text-decoration:none;letter-spacing:.02em;}
.crumb a:hover{color:var(--coral);}
.pager{display:flex;justify-content:space-between;gap:12px;margin-top:40px;padding-top:20px;border-top:1px solid var(--line);flex-wrap:wrap;}
.pager a{
  flex:1;min-width:180px;text-decoration:none;color:var(--ink);background:var(--card);
  border:1px solid var(--line);border-radius:10px;padding:12px 16px;font-size:13px;transition:.15s;
}
.pager a:hover{border-color:var(--coral);}
.pager a .dir{display:block;font-size:10px;font-weight:800;letter-spacing:.1em;text-transform:uppercase;color:var(--muted);margin-bottom:2px;}
.pager a .lab{font-weight:800;color:var(--ink);font-size:14px;}
.pager a.next{text-align:right;}

/* ---------- Diagrams ---------- */
.diagram{margin:22px 0;padding:20px;background:var(--card);border:1px solid var(--line);border-radius:12px;}
.diagram .dcap{font-size:11px;font-weight:800;letter-spacing:.1em;text-transform:uppercase;color:var(--coral);margin-bottom:12px;}
.diagram svg{display:block;width:100%;height:auto;}

/* Fee vs Equity two-panel */
.fe{display:grid;grid-template-columns:1fr 1fr;gap:0;border-radius:12px;overflow:hidden;border:1px solid var(--line);margin:20px 0;}
.fe > div{padding:20px;}
.fe .fee{background:#f4f4f4;}
.fe .eq{background:var(--ink);color:#eaeaea;}
.fe .eq strong{color:#fff;}
.fe h4{margin-top:0;}
.fe .eq h4{color:#fff;}
.fe .big{font-family:'Montserrat',sans-serif;font-weight:800;font-size:22px;line-height:1.1;margin:8px 0;}
.fe .fee .big{color:var(--ink);}
.fe .eq .big{color:var(--coral);}

/* Value bridge bars */
.bridge{display:flex;align-items:flex-end;gap:6px;height:180px;margin:10px 0 4px;}
.bridge .bar{flex:1;display:flex;flex-direction:column;justify-content:flex-end;align-items:center;height:100%;}
.bridge .bar .fill{width:100%;border-radius:6px 6px 0 0;}
.bridge .bar .val{font-weight:800;font-size:12px;color:var(--ink);margin-bottom:4px;}
.bridge .bar .lab{font-size:10.5px;color:var(--muted);text-align:center;margin-top:6px;line-height:1.3;}

/* Ladder */
.ladder{display:flex;flex-direction:column-reverse;gap:8px;margin:18px 0;}
.rung{display:flex;align-items:stretch;gap:0;border-radius:10px;overflow:hidden;border:1px solid var(--line);}
.rung .lvl{flex:none;width:70px;background:var(--ink);color:#fff;display:flex;flex-direction:column;align-items:center;justify-content:center;padding:12px 6px;text-align:center;}
.rung .lvl .r{font-family:'Montserrat',sans-serif;font-weight:800;font-size:20px;line-height:1;}
.rung .lvl .rs{font-size:9px;letter-spacing:.06em;text-transform:uppercase;opacity:.7;margin-top:3px;}
.rung .rc{flex:1;padding:12px 16px;background:#fff;}
.rung .rc .rt{font-weight:800;color:var(--ink);font-size:15px;}
.rung .rc .rd{font-size:13px;color:var(--body);margin-top:2px;}
.rung.here{border-color:var(--coral);border-width:2px;}
.rung.here .lvl{background:var(--coral);}
.rung.top .lvl{background:linear-gradient(180deg,#FF4F47,#c62c25);}

.ladder-axis{display:flex;justify-content:space-between;font-size:11px;color:var(--muted);font-weight:700;margin:2px 4px 0;}

/* callout inline */
.you{background:var(--coral-soft);border-radius:6px;padding:1px 6px;font-weight:700;color:var(--coral);}

.qbox{background:var(--card);border:1px solid var(--line);border-radius:10px;padding:14px 16px;margin:12px 0;}
.qbox .ql{font-size:10px;font-weight:800;letter-spacing:.1em;text-transform:uppercase;color:var(--coral);margin-bottom:8px;}
.qbox ol{margin:0;padding-left:20px;}
.qbox ol li{margin:7px 0;font-size:14px;}

hr.sep{border:none;border-top:1px solid var(--line);margin:38px 0;}

.note{font-size:13px;color:var(--muted);font-style:italic;}

/* ---------- Responsive ---------- */
@media (max-width:760px){
  body{font-size:15.5px;}
  .page{margin:0;padding:26px 20px 44px;border-radius:0;box-shadow:none;}
  h1.title{font-size:26px;}
  h2{font-size:21px;margin-top:38px;}
  .navgrid{grid-template-columns:1fr;}
  .grid2,.grid3,.fe{grid-template-columns:1fr;}
  .fe{border-radius:12px;}
  .head-meta{font-size:10px;}
  .brand .wm{font-size:17px;}
  .bridge{height:150px;}
  .rung .lvl{width:58px;}
}
@media (max-width:420px){
  .page{padding:22px 15px 40px;}
  h1.title{font-size:23px;}
  .fe .big{font-size:19px;}
  .takeaways li{padding-left:48px;font-size:14px;}
  .pager a{min-width:100%;}
}