:root{--bg:#f3efe5;--paper:#fffdf7;--ink:#27231d;--muted:#6d6558;--rule:#263b51;--red:#9b3f2f;--gold:#9b7a33;--line:rgba(39,35,29,.16);--measure:760px}
*{box-sizing:border-box}
html{-webkit-text-size-adjust:100%;scroll-behavior:smooth}
body{margin:0;background:linear-gradient(140deg,#f6f1e6,#eee8da);color:var(--ink);font-family:"Noto Serif SC","Source Han Serif SC","Songti SC",serif;font-size:18px;line-height:2.04}
a{color:inherit}

/* ---- top nav ---- */
.top{position:sticky;top:0;z-index:10;display:flex;justify-content:space-between;gap:12px;align-items:center;padding:11px 22px;background:rgba(243,239,229,.95);backdrop-filter:blur(10px);border-bottom:1px solid var(--line);font-size:13px}
.top a{text-decoration:none;color:var(--red)}
.modes{display:flex;gap:7px;flex-wrap:wrap}
.pill{padding:4px 11px;border:1px solid var(--line);color:var(--muted)!important;border-radius:2px;transition:border-color .18s ease,color .18s ease,background .18s ease}
.pill:not(.on):hover{border-color:var(--red);color:var(--red)!important}
.pill.on{background:var(--rule);border-color:var(--rule);color:#fff!important}

/* ---- header ---- */
header{max-width:900px;margin:auto;padding:72px 24px 28px;text-align:center}
.series{font-size:11px;letter-spacing:.34em;color:var(--red)}
h1{font-size:clamp(30px,5vw,48px);line-height:1.36;margin:22px auto 14px;max-width:820px}
.subtitle{max-width:720px;margin:auto;color:var(--muted);font-size:17px}
.meta{font-size:12px;letter-spacing:.08em;color:#8c8374;margin-top:22px}

/* ---- article body ---- */
main{max-width:var(--measure);margin:auto;background:var(--paper);border-top:3px solid var(--rule);box-shadow:0 18px 65px rgba(39,35,29,.08);padding:44px 52px 70px;counter-reset:sec}
.lead{font-size:19px;line-height:2.04;margin:0 0 40px;padding:26px 30px;border-left:3px solid var(--red);background:#faf6ed;border-radius:0 3px 3px 0}
h2{font-size:25px;line-height:1.55;margin:70px 0 22px;padding-top:26px;border-top:1px solid var(--line);color:var(--rule)}
main>h2{counter-increment:sec}
main>h2::before{content:counter(sec,decimal-leading-zero);display:block;font-family:Georgia,"Times New Roman",serif;font-size:13px;letter-spacing:.3em;color:var(--red);font-weight:400;margin-bottom:9px}
h3{font-size:19px;line-height:1.65;margin:38px 0 13px;color:var(--red)}
p{margin:0 0 18px;text-align:justify}
strong{color:var(--rule)}
blockquote{margin:36px 0;padding:24px 30px;background:#f7f2e8;border-top:1px solid var(--gold);border-bottom:1px solid var(--gold);font-size:20px;font-weight:600;text-align:center;letter-spacing:.01em}
ul,ol{padding-left:1.5em;margin:0 0 22px}
li{margin:0 0 11px}

/* ---- cards ---- */
.card{margin:30px 0;padding:24px 27px;border:1px solid var(--line);background:#fcfaf4;border-radius:3px;box-shadow:0 1px 0 rgba(39,35,29,.03)}
.card h3{margin-top:0;padding-left:14px;border-left:3px solid var(--gold)}
.card p:last-child{margin-bottom:0}
.takeaway{margin-top:17px;padding-top:15px;border-top:1px dashed var(--line);color:var(--muted);font-size:17px}
.takeaway strong{color:var(--red)}

/* ---- formula / warning ---- */
.formula{font-family:Georgia,"Times New Roman",serif;background:#f0ece2;border-left:4px solid var(--rule);padding:19px 24px;margin:28px 0;font-size:18px;line-height:1.95;border-radius:0 3px 3px 0}
.warning{border-color:rgba(155,63,47,.35);background:#fff6f1}
.warning h3{border-left-color:var(--red)}

/* ---- footer / pair ---- */
.end{margin-top:66px;padding-top:30px;border-top:2px solid var(--rule);text-align:center;color:var(--muted);font-size:14px}
.end a{color:var(--red);text-decoration:none}
.end a:hover{text-decoration:underline}
.pair{display:grid;grid-template-columns:1fr 1fr;gap:14px;margin:34px 0}
.pair a{display:block;padding:18px 20px;border:1px solid var(--line);text-decoration:none;border-radius:3px;transition:border-color .18s ease,color .18s ease,transform .18s ease,box-shadow .18s ease}
.pair a:hover{border-color:var(--red);color:var(--red);transform:translateY(-2px);box-shadow:0 9px 24px rgba(39,35,29,.09)}

/* ---- catalog / landing ---- */
.catalog{max-width:1100px}
.catalog main{max-width:1040px}
.grid{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:20px}
.entry{padding:24px;border:1px solid var(--line);background:#fffdf7;border-radius:3px;transition:border-color .18s ease,transform .18s ease,box-shadow .18s ease}
.entry:hover{border-color:var(--red);transform:translateY(-2px);box-shadow:0 11px 28px rgba(39,35,29,.08)}
.entry h2{font-size:22px;margin:0 0 10px;padding:0;border:0}
.entry h2::before{content:none}
.entry p{font-size:15.5px;color:var(--muted)}
.entry-links{display:flex;gap:8px;flex-wrap:wrap}
.entry-links a{font-size:13px;text-decoration:none;border:1px solid var(--line);padding:6px 11px;color:var(--red);border-radius:2px;transition:background .18s ease,color .18s ease,border-color .18s ease}
.entry-links a:hover{background:var(--red);color:#fff;border-color:var(--red)}

/* ---- responsive ---- */
@media(max-width:760px){
body{font-size:17px}
.top{padding:9px 12px;align-items:flex-start}
.top .hide-sm{display:none}
header{padding:48px 18px 22px}
main{padding:32px 20px 52px;border-left:0;border-right:0}
.lead{padding:20px 18px}
.pair,.grid{grid-template-columns:1fr}
h2{font-size:22px;margin-top:54px}
main>h2::before{font-size:12px;margin-bottom:7px}
.formula{font-size:16px;overflow-wrap:anywhere}
.card{padding:20px 20px}
}

/* ---- print ---- */
@media print{
body{background:#fff}
.top{display:none}
header{padding-top:32px}
main{box-shadow:none;border-top:1px solid #000;padding:20px 0;max-width:100%}
h2{page-break-after:avoid}
.card,blockquote{page-break-inside:avoid}
.pair a:hover,.entry:hover{transform:none;box-shadow:none}
}