/* DARK TREATMENT: a command-centre index — hairline-separated readings on an
   open canvas, a recessed letter rail, and exactly one glow (search focus). */
*{box-sizing:border-box}
body{margin:0;padding-top:18px;background:var(--bg);color:var(--text);font:14.5px/1.55 var(--font-ui);-webkit-font-smoothing:antialiased}
a{color:inherit;text-decoration:none}
.gl-shell{max-width:1120px;margin:0 auto;padding:clamp(28px,5vw,64px) clamp(18px,4vw,44px) 80px}
.gl-hero{max-width:760px;padding:18px 0 30px;position:relative}
.gl-hero::before{content:"";position:absolute;left:-28px;top:10px;bottom:30px;width:2px;background:linear-gradient(180deg,var(--link),transparent)}
.gl-kicker{display:block;margin:0 0 14px;color:var(--muted);font:650 11px/1 var(--font-mono);letter-spacing:.14em;text-transform:uppercase}
.gl-hero h1{margin:0;font:760 clamp(34px,6vw,64px)/1 var(--font-ui);letter-spacing:-.045em}
.gl-lede{margin:16px 0 0;max-width:56ch;color:var(--muted);font-size:clamp(14px,2vw,16px)}

.gl-rail{position:sticky;top:0;z-index:5;display:flex;flex-wrap:wrap;gap:2px;padding:10px 12px;background:var(--panel2);border-top:1px solid var(--line);border-bottom:1px solid var(--line)}
.gl-letter{display:flex;flex-direction:column;align-items:center;gap:5px;min-width:26px;min-height:44px;padding:6px 4px;border-radius:var(--r-ctl,8px);color:var(--muted);font:650 11px/1 var(--font-mono);letter-spacing:.06em}
.gl-letter:hover,.gl-letter:focus-visible{outline:none;color:var(--text);box-shadow:inset 0 -1px 0 var(--link)}
.gl-tick{display:block;width:2px;height:calc(3px + var(--n) * 2px);max-height:16px;border-radius:0;background:var(--link);opacity:.75}
.gl-letter.is-empty{color:color-mix(in srgb,var(--muted) 45%,transparent);cursor:default}
.gl-letter.is-empty .gl-tick{height:3px;background:var(--line);opacity:1}
.gl-rail-note{margin:8px 0 22px;color:var(--muted);font:600 11px/1.4 var(--font-mono);letter-spacing:.08em;text-transform:uppercase}

.gl-controls{display:grid;grid-template-columns:minmax(220px,1fr) auto;gap:14px;align-items:center;padding:16px 0 24px;border-top:1px solid var(--line)}
.gl-search{position:relative;max-width:520px}
.gl-search input{width:100%;min-height:44px;padding:10px 42px 10px 14px;border:1px solid var(--line);border-radius:var(--r-ctl,8px);background:var(--panel2);color:var(--text);font:inherit;outline:none}
.gl-search input:focus{border-color:var(--link);box-shadow:0 0 16px -5px color-mix(in srgb,var(--link) 55%,transparent)}
.gl-search svg{position:absolute;right:14px;top:13px;width:18px;height:18px;fill:none;stroke:var(--muted);stroke-width:1.8}
.gl-filters{display:flex;flex-wrap:wrap;justify-content:flex-end;gap:7px}
.gl-filter{min-height:44px;padding:8px 13px;border:1px solid var(--line);border-radius:var(--r-pill,999px);background:transparent;color:var(--muted);font:650 12px/1 var(--font-ui);cursor:pointer}
.gl-filter:hover,.gl-filter[aria-pressed="true"]{border-color:color-mix(in srgb,var(--link) 65%,var(--line));color:var(--text);background:var(--panel2)}
.gl-meta{display:flex;justify-content:space-between;gap:16px;margin:0 0 20px;color:var(--muted);font:600 11px/1.4 var(--font-mono);letter-spacing:.08em;text-transform:uppercase}

.gl-domain{margin:0 0 40px}
.gl-domain[hidden]{display:none}
.gl-domain-h{display:flex;align-items:baseline;justify-content:space-between;gap:16px;margin:0;padding:0 0 12px;border-bottom:1px solid var(--line);font:680 clamp(20px,2.6vw,26px)/1.2 var(--font-ui);letter-spacing:-.02em}
.gl-domain-n{color:var(--muted);font:650 11px/1 var(--font-mono);letter-spacing:.1em}
.gl-list{margin:0}
.gl-row{position:relative;display:grid;grid-template-columns:minmax(0,260px) minmax(0,1fr);gap:8px 28px;padding:18px 14px 18px 0;border-bottom:1px solid var(--line);scroll-margin-top:96px;transition:background .16s ease}
.gl-row:hover{background:var(--panel)}
.gl-row[hidden]{display:none}
.gl-term{margin:0;display:flex;flex-direction:column;gap:7px;min-width:0}
.gl-term-name{font:680 var(--fs-h2)/1.3 var(--font-ui);letter-spacing:-.01em}
.gl-src{align-self:flex-start;padding:3px 8px;border:1px solid var(--line);border-radius:var(--r-pill,999px);color:var(--muted);font:650 var(--fs-micro)/1.5 var(--font-mono);letter-spacing:.07em;transition:border-color .16s ease,color .16s ease}
.gl-row:hover .gl-src{border-color:color-mix(in srgb,var(--link) 45%,var(--line));color:var(--text)}
.gl-def{margin:0;min-width:0;max-width:62ch}
.gl-answer{margin:0;font-size:var(--fs-md)}
.gl-why{margin:9px 0 0;color:var(--muted);font-size:var(--fs-sm)}
.gl-why-k{display:inline-block;margin-right:8px;color:var(--link);font:650 var(--fs-micro)/1 var(--font-mono);letter-spacing:.1em;text-transform:uppercase}
.gl-anchor{display:block;position:absolute;top:-96px;height:0;visibility:hidden}
.gl-domain-empty{margin:0;padding:22px 0 0;color:var(--muted);font:650 12px/1.5 var(--font-mono);letter-spacing:.08em;text-transform:uppercase}
.gl-state-panel{padding:44px 22px;border:1px dashed var(--line);color:var(--muted);text-align:center;font:650 12px/1.5 var(--font-mono);letter-spacing:.08em;text-transform:uppercase}
.gl-domain-empty[hidden],.gl-state-panel[hidden]{display:none}

/* LIGHT TREATMENT: a research workspace. Four mechanisms differ on purpose —
   M1 separation moves from row rules to white card material; M2 hover reverses
   direction; M3 the rail inverts from recessed slot to raised strip; M4 glow
   becomes a flat halo. Everything else is byte-shared with dark. */
html[data-theme="light"] .gl-hero::before{background:var(--link)}
html[data-theme="light"] .gl-search input{background:var(--panel);box-shadow:0 1px 2px color-mix(in srgb,var(--text) 7%,transparent)}
html[data-theme="light"] .gl-search input:focus{box-shadow:0 0 0 3px color-mix(in srgb,var(--link) 16%,transparent)}
/* M1 */
html[data-theme="light"] .gl-domain{padding:6px 20px 12px;background:var(--panel);border:1px solid var(--line);border-radius:var(--r-card,12px);box-shadow:0 8px 24px color-mix(in srgb,var(--text) 7%,transparent)}
html[data-theme="light"] .gl-domain-h{padding-top:16px}
html[data-theme="light"] .gl-row{border-bottom-color:color-mix(in srgb,var(--line) 60%,transparent)}
html[data-theme="light"] .gl-list .gl-row:last-child{border-bottom:0}
/* M2 */
html[data-theme="light"] .gl-row:hover{background:var(--panel2)}
html[data-theme="light"] .gl-src{background:var(--panel2)}
/* M3 */
html[data-theme="light"] .gl-rail{background:var(--panel);border-top:0;box-shadow:0 6px 18px color-mix(in srgb,var(--text) 6%,transparent)}
/* M4 */
html[data-theme="light"] .gl-letter:hover,html[data-theme="light"] .gl-letter:focus-visible{box-shadow:0 0 0 2px color-mix(in srgb,var(--link) 18%,transparent)}

@media (max-width:900px){
  .gl-row{grid-template-columns:1fr;gap:10px;padding:16px 12px 16px 0}
  .gl-def{max-width:none}
}
@media (max-width:760px){
  .gl-controls{grid-template-columns:1fr;align-items:stretch}
  .gl-search{max-width:none}
  .gl-filters{justify-content:flex-start}
}
@media (max-width:600px){
  .gl-shell{padding:24px 16px 58px}
  .gl-hero{padding:12px 12px 26px}
  .gl-hero::before{left:0;top:8px;bottom:26px}
  .gl-rail{flex-wrap:nowrap;overflow-x:auto;gap:1px;padding:8px 6px;-webkit-overflow-scrolling:touch}
  .gl-letter{min-width:24px}
  html[data-theme="light"] .gl-domain{padding:4px 14px 10px}
}
@media (prefers-reduced-motion:reduce){.gl-row,.gl-src,.gl-letter{transition:none}}