:root{
  /* navy on warm white — unified theme */
  --paper:#FBF7EE;
  --paper-panel:#F4EEDF;
  --navy:#13294B;
  --navy-deep:#0D1F3C;
  --slate:#54678A;
  --dim:#54678A;
  --slate-dim:#8290AB;
  --dim-2:#8290AB;
  --line:rgba(19,41,75,.15);
  --line-strong:rgba(19,41,75,.32);
  --red:#B3122B;            /* construct accent — clickable */
  --red-dim:rgba(179,18,43,.5);
  --amber:#9A7C2E;          /* handoff / status */
  --mono:Consolas,'IBM Plex Mono','SF Mono',Menlo,Monaco,'Liberation Mono',monospace;
  --maxw:860px;
}
*{margin:0;padding:0;box-sizing:border-box}
body{
  background:var(--paper);color:var(--navy);
  font-family:var(--mono);font-size:.94rem;line-height:1.75;
  -webkit-font-smoothing:antialiased;
}
::selection{background:var(--navy);color:var(--paper)}
a{color:var(--amber);text-decoration:none}
a:hover{text-decoration:underline;text-underline-offset:3px}
a:focus-visible{outline:2px solid var(--navy);outline-offset:3px;border-radius:2px}
.wrap{max-width:var(--maxw);margin:0 auto;padding:0 24px}

.eyebrow{font-size:.7rem;letter-spacing:.22em;text-transform:uppercase;color:var(--slate)}

/* chrome */
.site-head{border-bottom:1px solid var(--line);position:sticky;top:0;z-index:10;background:rgba(251,247,238,.94);backdrop-filter:blur(8px)}
.nav{display:flex;align-items:center;justify-content:space-between;height:60px}
.wordmark{display:flex;align-items:baseline;gap:12px;color:var(--navy-deep)}
.wordmark:hover{text-decoration:none}
.wordmark .sigil{font-weight:600;font-size:1.15rem;color:var(--navy-deep)}
.wordmark .full{font-size:.68rem;letter-spacing:.18em;text-transform:uppercase;color:var(--slate)}
.links{display:flex;gap:24px}
.links a{font-size:.72rem;letter-spacing:.14em;text-transform:uppercase;color:var(--slate)}
.links a:hover{color:var(--navy-deep);text-decoration:none}
@media(max-width:640px){.wordmark .full{display:none}}

main.wrap{padding-top:56px;padding-bottom:96px}

.site-foot{border-top:1px solid var(--line);background:var(--paper-panel);padding:26px 0}
.site-foot .wrap{display:flex;justify-content:space-between;flex-wrap:wrap;gap:12px}
.fine{font-size:.68rem;letter-spacing:.12em;text-transform:uppercase;color:var(--slate-dim)}

/* chips */
.chip{display:inline-block;font-size:.64rem;font-weight:500;letter-spacing:.16em;text-transform:uppercase;padding:3px 10px;border-radius:2px;border:1px solid var(--line-strong);color:var(--slate)}
.chip-tier{background:var(--navy);border-color:var(--navy);color:var(--paper)}
.chip-kind{border-color:var(--line-strong);color:var(--navy)}
.chip-unfinished{border-color:var(--amber);color:var(--amber);background:rgba(154,124,46,.08)}

/* masthead */
.masthead{border-bottom:1px solid var(--line-strong);padding-bottom:28px;margin-bottom:44px}
.mast-row{display:flex;gap:8px;flex-wrap:wrap;margin-bottom:18px}
.masthead h1{font-size:clamp(1.7rem,4vw,2.4rem);font-weight:600;letter-spacing:-.02em;color:var(--navy-deep);line-height:1.2;margin-bottom:14px}
.lineage{font-size:.72rem;color:var(--slate);letter-spacing:.04em;margin-bottom:18px}
.lineage .sep{color:var(--slate-dim);margin:0 6px}
.lineage .self{color:var(--navy-deep);font-weight:500}
.mast-meta{display:flex;gap:36px;flex-wrap:wrap}
.mast-meta dt{font-size:.62rem;letter-spacing:.2em;text-transform:uppercase;color:var(--slate-dim)}
.mast-meta dd{font-size:.82rem;color:var(--navy)}

/* paper body */
.paper-body h1{font-size:1.35rem;font-weight:600;letter-spacing:.04em;text-transform:uppercase;color:var(--navy-deep);margin:56px 0 20px;padding-top:24px;border-top:1px solid var(--line)}
.paper-body h1::before{content:"# ";color:var(--red)}
.paper-body h1:first-child{margin-top:0;border-top:none;padding-top:0}
.paper-body h2{font-size:1.1rem;font-weight:600;color:var(--navy-deep);margin:38px 0 14px}
.paper-body h2::before{content:"## ";color:var(--red-dim)}
.paper-body p{margin:0 0 18px;max-width:72ch}
.paper-body ul,.paper-body ol{margin:0 0 18px 22px;max-width:72ch}
.paper-body li{margin-bottom:6px}
.paper-body li::marker{color:var(--red-dim)}
.paper-body strong{font-weight:600;color:var(--navy-deep)}
.paper-body em{color:var(--slate)}
.paper-body code{background:var(--paper-panel);padding:1px 5px;border-radius:2px;font-size:.88em;color:var(--amber)}

/* constructs */
.construct{border:1px solid var(--line);border-left:2px solid var(--red-dim);padding:16px 20px 4px;margin:0 0 22px;background:#fff9;max-width:76ch}
.construct .construct-label{display:inline-block;font-size:.68rem;font-weight:600;letter-spacing:.16em;text-transform:uppercase;color:var(--red);margin-bottom:8px}
a.construct-label{color:var(--red)}
a.construct-label::after{content:" ›";color:var(--red-dim)}
a.construct-label:hover{text-decoration:underline;text-underline-offset:3px}
.construct p{margin-bottom:14px}
.construct.definition{border-left-color:var(--red)}
.construct.axiom{border-left-color:var(--red);background:rgba(179,18,43,.05)}
.construct.model,.construct.theorem{border-left-color:var(--red)}
.construct.primitive{border-left-color:var(--red);border-style:double;border-width:3px 1px 1px 3px}
.construct.refinement,.construct.derivation{border-left-style:dashed}
aside.construct.remark{border:1px solid var(--line);border-left:2px solid var(--red-dim);background:var(--paper-panel);padding:12px 18px 0;margin:0 0 22px;max-width:76ch;color:var(--navy);font-size:.9rem}
aside.construct.remark .construct-label,aside.construct.remark a.construct-label{color:var(--red-dim)}
aside.construct.remark p{color:var(--slate);margin-bottom:12px}
.construct.handoff{border-left-color:var(--amber);background:var(--paper-panel)}
.construct.handoff .construct-label{color:var(--amber)}
.xref{color:var(--red);border-bottom:1px dotted var(--red-dim);white-space:nowrap}
.xref:hover{text-decoration:none;border-bottom-style:solid}
.xref.unresolved{color:var(--slate-dim);border-bottom:1px dotted var(--slate-dim)}
.construct:target{outline:2px solid var(--red);outline-offset:2px}

/* index / listing pages */
.home-intro{padding:20px 0 40px;border-bottom:1px solid var(--line-strong);margin-bottom:48px}
.home-intro h1{font-size:clamp(1.7rem,4.4vw,2.5rem);font-weight:600;letter-spacing:-.02em;color:var(--navy-deep);margin:12px 0 14px}
.home-intro p{color:var(--slate);max-width:60ch}
.section-title{font-size:.85rem;font-weight:600;letter-spacing:.2em;text-transform:uppercase;color:var(--navy-deep);margin:48px 0 20px}
.section-title::before{content:"# ";color:var(--red)}
.tier-group{margin-bottom:34px}
.tier-label{font-size:.74rem;font-weight:600;letter-spacing:.16em;text-transform:uppercase;color:var(--red);margin-bottom:10px}
.paper-list{list-style:none;border:1px solid var(--line)}
.paper-list li{display:flex;justify-content:space-between;gap:16px;flex-wrap:wrap;padding:13px 18px;border-bottom:1px solid var(--line)}
.paper-list li:last-child{border-bottom:none}
.paper-list li:hover{background:var(--paper-panel)}
.paper-list li a{color:var(--navy)}
.paper-list li a:hover{color:var(--red)}
.paper-list .meta{font-size:.72rem;color:var(--slate-dim)}