/* ============================================================
   TMUA Lab — base, chrome, shared components
   ============================================================ */

*, *::before, *::after { box-sizing: border-box; }

html { -webkit-text-size-adjust: 100%; scroll-behavior: smooth; }

body {
  margin: 0;
  background: var(--bg);
  color: var(--text);
  font-family: var(--font-sans);
  font-size: 16px;
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  overflow-x: hidden;
}

body::before {
  content: "";
  position: fixed; inset: 0;
  pointer-events: none; z-index: 0;
  background:
    linear-gradient(to right, var(--grid-line) 1px, transparent 1px) 0 0 / 72px 72px,
    linear-gradient(to bottom, var(--grid-line) 1px, transparent 1px) 0 0 / 72px 72px,
    radial-gradient(1100px 620px at 78% -8%, color-mix(in srgb, var(--accent) 8%, transparent), transparent 70%),
    radial-gradient(900px 520px at 8% 4%, color-mix(in srgb, var(--accent-2) 6%, transparent), transparent 70%);
  mask-image: linear-gradient(to bottom, #000 0%, #000 46%, transparent 92%);
}

body > * { position: relative; z-index: 1; }

h1, h2, h3, h4 { font-family: var(--font-display); font-weight: 600; letter-spacing: -0.02em; margin: 0; line-height: 1.12; }
p { margin: 0 0 1em; }
a { color: inherit; text-decoration: none; }
button, input, select, textarea { font: inherit; color: inherit; }
img, svg { max-width: 100%; }
hr { border: 0; border-top: 1px solid var(--border); margin: 0; }

::selection { background: color-mix(in srgb, var(--accent) 32%, transparent); color: var(--text); }

:focus-visible {
  outline: 2px solid var(--accent);
  outline-offset: 2px;
  border-radius: 3px;
}

/* ---------- layout ---------- */

.wrap { width: 100%; max-width: var(--maxw); margin-inline: auto; padding-inline: var(--gutter); }
.wrap-wide { max-width: 1400px; }

.skip {
  position: absolute; left: -9999px; top: 0; z-index: 200;
  background: var(--accent); color: var(--accent-ink);
  padding: 10px 16px; border-radius: 0 0 var(--radius) 0; font-weight: 600;
}
.skip:focus { left: 0; }

/* ---------- micro type ---------- */

.eyebrow {
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.18em;
  text-transform: uppercase;
  color: var(--muted);
  display: flex; align-items: center; gap: 10px;
}
.eyebrow::after { content: ""; flex: 1; height: 1px; background: var(--border); }

.num {
  font-family: var(--font-mono);
  font-size: 11px;
  color: var(--accent);
  letter-spacing: 0.1em;
}

.mono { font-family: var(--font-mono); font-variant-numeric: tabular-nums; }
.muted { color: var(--muted); }
.soft  { color: var(--text-soft); }
.nowrap { white-space: nowrap; }

/* ---------- header ---------- */

.hdr {
  position: sticky; top: 0; z-index: 90;
  background: var(--header-bg);
  backdrop-filter: saturate(160%) blur(14px);
  -webkit-backdrop-filter: saturate(160%) blur(14px);
  box-shadow: var(--header-shadow);
}
.hdr-in {
  display: flex; align-items: center; gap: 18px;
  height: 60px;
}
.brand { display: flex; align-items: center; gap: 10px; font-family: var(--font-display); font-weight: 600; letter-spacing: -0.02em; font-size: 16px; }
.brand .mark {
  width: 26px; height: 26px; display: grid; place-items: center;
  border-radius: 7px;
  background: linear-gradient(150deg, var(--accent), var(--accent-2));
  color: var(--accent-ink);
  font-family: var(--font-mono); font-size: 12px; font-weight: 700;
  box-shadow: 0 4px 14px -6px color-mix(in srgb, var(--accent) 60%, transparent);
}
.brand em { font-style: normal; color: var(--muted); font-weight: 400; }

.nav { display: flex; align-items: center; gap: 2px; margin-left: 8px; flex: 1; min-width: 0; }
.nav a {
  display: inline-flex; align-items: baseline; gap: 7px;
  padding: 7px 11px; border-radius: var(--radius-sm);
  font-size: 13.5px; color: var(--text-soft);
  transition: background var(--t-fast), color var(--t-fast);
  white-space: nowrap;
}
.nav a i { font-style: normal; font-family: var(--font-mono); font-size: 9.5px; color: var(--faint); letter-spacing: .06em; }
.nav a:hover { background: var(--tint-strong); color: var(--text); }
.nav a[aria-current="page"] { color: var(--text); background: var(--tint-strong); }
.nav a[aria-current="page"] i { color: var(--accent); }

.hdr-right { display: flex; align-items: center; gap: 8px; margin-left: auto; }

.kbd-btn {
  display: inline-flex; align-items: center; gap: 6px;
  background: var(--tint); border: 1px solid var(--border);
  color: var(--muted); padding: 6px 9px; border-radius: var(--radius-sm);
  font-family: var(--font-mono); font-size: 11.5px; cursor: pointer;
  transition: all var(--t-fast);
}
.kbd-btn:hover { border-color: var(--border-strong); color: var(--text); background: var(--tint-strong); }

.burger { display: none; }

@media (max-width: 1020px) {
  .nav { display: none; }
  .burger {
    display: inline-grid; place-items: center;
    width: 34px; height: 34px; border-radius: var(--radius-sm);
    background: var(--tint); border: 1px solid var(--border); cursor: pointer;
  }
  .burger span { display: block; width: 15px; height: 1.5px; background: var(--text); box-shadow: 0 -5px 0 var(--text), 0 5px 0 var(--text); }
  .nav.open {
    display: flex; flex-direction: column; align-items: stretch; gap: 2px;
    position: absolute; top: 60px; left: 0; right: 0;
    background: var(--header-solid); border-top: 1px solid var(--border);
    padding: 10px var(--gutter) 16px; box-shadow: var(--shadow-lift);
  }
  .nav.open a { padding: 11px 12px; font-size: 15px; }
}

/* ---------- buttons ---------- */

.btn {
  display: inline-flex; align-items: center; justify-content: center; gap: 9px;
  padding: 11px 20px; border-radius: var(--radius);
  border: 1px solid transparent; cursor: pointer;
  font-size: 14.5px; font-weight: 500; letter-spacing: -0.005em;
  transition: transform var(--t-fast) var(--ease-out), background var(--t-fast), border-color var(--t-fast), box-shadow var(--t-fast), color var(--t-fast);
  text-align: center;
}
.btn:active { transform: translateY(1px) scale(0.995); }
.btn:disabled { opacity: 0.45; cursor: not-allowed; }

.btn-primary { background: var(--cta-bg); color: var(--cta-ink); font-weight: 600; }
.btn-primary:hover:not(:disabled) { background: var(--cta-hover); box-shadow: 0 12px 30px -18px rgba(0,0,0,.9); }

.btn-accent { background: var(--accent); color: var(--accent-ink); font-weight: 600; }
.btn-accent:hover:not(:disabled) { background: color-mix(in srgb, var(--accent) 88%, white); box-shadow: var(--glow-accent); }

.btn-ghost { background: var(--tint); border-color: var(--border-strong); color: var(--text); }
.btn-ghost:hover:not(:disabled) { background: var(--tint-strong); border-color: var(--accent); color: var(--text); }

.btn-quiet { background: transparent; border-color: var(--border); color: var(--muted); }
.btn-quiet:hover:not(:disabled) { color: var(--text); border-color: var(--border-strong); }

.btn-sm { padding: 7px 13px; font-size: 13px; border-radius: var(--radius-sm); }
.btn-lg { padding: 14px 26px; font-size: 15.5px; }
.btn-block { width: 100%; }

/* ---------- panels & chips ---------- */

.panel {
  background: var(--panel);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow-soft);
}
.panel-flat { background: var(--tint); box-shadow: none; }

.chip {
  display: inline-flex; align-items: center; gap: 6px;
  padding: 3px 9px; border-radius: 999px;
  border: 1px solid var(--border-strong);
  font-family: var(--font-mono); font-size: 10.5px;
  letter-spacing: 0.08em; text-transform: uppercase; color: var(--muted);
  white-space: nowrap;
}
.chip-p1 { color: var(--p1); border-color: color-mix(in srgb, var(--p1) 40%, transparent); background: var(--p1-soft); }
.chip-p2 { color: var(--p2); border-color: color-mix(in srgb, var(--p2) 40%, transparent); background: var(--p2-soft); }
.chip-good { color: var(--good); border-color: color-mix(in srgb, var(--good) 40%, transparent); }
.chip-bad  { color: var(--bad);  border-color: color-mix(in srgb, var(--bad) 40%, transparent); }
.chip-warn { color: var(--warn); border-color: color-mix(in srgb, var(--warn) 40%, transparent); }

kbd {
  display: inline-block; min-width: 20px; text-align: center;
  padding: 1px 6px; border-radius: 5px;
  background: var(--tint-strong); border: 1px solid var(--border-strong);
  border-bottom-width: 2px;
  font-family: var(--font-mono); font-size: 11.5px; color: var(--text-soft);
}

/* ---------- maths rendering ---------- */

.m { font-family: var(--font-math); font-size: 1.06em; letter-spacing: 0; white-space: nowrap; }
.m .v  { font-style: italic; }
.m .op { font-family: var(--font-math); font-style: normal; padding: 0 .13em; }
.m .op.un { padding: 0 0 0 .13em; }
.m .fn { font-style: normal; padding-right: .1em; }
.m sup { font-size: 0.68em; vertical-align: 0.55em; line-height: 0; }
.m sub { font-size: 0.68em; vertical-align: -0.28em; line-height: 0; }

/* inline-block + overflow:hidden puts the box's baseline on its bottom edge,
   which is the only way to sit a two-line fraction on the maths axis. */
.m .frac {
  display: inline-block; overflow: hidden; text-align: center;
  vertical-align: -0.85em; margin: 0 .16em;
  font-size: 0.84em; line-height: 1.22;
}
.m .frac > span { display: block; padding: 0 .28em; }
.m .frac > span:first-child { border-bottom: 1px solid currentColor; }
.m .frac.binom > span:first-child { border-bottom: 0; }

.m .rad { display: inline-flex; align-items: stretch; margin: 0 .08em; }
.m .rad > .sign { font-size: 1.05em; }
.m .rad > .bod { border-top: 1px solid currentColor; padding: 0 .16em; margin-top: .16em; }

.m .par { font-style: normal; }

.m-block { display: block; text-align: center; margin: 1em 0; white-space: normal; }

/* ---------- footer ---------- */

.ftr {
  margin-top: 88px;
  border-top: 1px solid var(--border);
  background: linear-gradient(to bottom, transparent, color-mix(in srgb, var(--panel) 55%, transparent));
}
.ftr-in { padding: 34px 0 44px; display: flex; flex-wrap: wrap; gap: 18px 34px; align-items: center; }
.ftr .disc { font-size: 12.5px; color: var(--faint); max-width: 560px; }
.ftr .links { margin-left: auto; display: flex; gap: 18px; font-size: 12.5px; color: var(--muted); flex-wrap: wrap; }
.ftr .links a:hover { color: var(--accent); }

/* ---------- command palette ---------- */

.pal-back {
  position: fixed; inset: 0; z-index: 200;
  background: color-mix(in srgb, var(--bg-deep) 72%, transparent);
  backdrop-filter: blur(6px);
  display: grid; place-items: start center;
  padding: 12vh 16px 16px;
  animation: fade var(--t-fast) var(--ease-out);
}
.pal {
  width: min(640px, 100%);
  background: var(--panel); border: 1px solid var(--border-strong);
  border-radius: var(--radius-lg); box-shadow: var(--shadow-lift);
  overflow: hidden;
  animation: pop var(--t-mid) var(--ease-spring);
}
.pal input {
  width: 100%; border: 0; background: transparent; padding: 17px 18px;
  font-size: 15.5px; outline: none;
  border-bottom: 1px solid var(--border);
}
.pal input::placeholder { color: var(--faint); }
.pal-list { max-height: min(52vh, 420px); overflow-y: auto; padding: 6px; }
.pal-item {
  display: flex; align-items: center; gap: 12px; width: 100%;
  padding: 9px 12px; border-radius: var(--radius-sm);
  background: transparent; border: 0; cursor: pointer; text-align: left;
}
.pal-item .ic { width: 22px; text-align: center; color: var(--accent); font-family: var(--font-mono); font-size: 12px; }
.pal-item .tt { flex: 1; font-size: 14px; }
.pal-item .sb { font-size: 11.5px; color: var(--faint); font-family: var(--font-mono); }
.pal-item[data-sel="1"] { background: var(--accent-soft); box-shadow: inset 0 0 0 1px color-mix(in srgb, var(--accent) 30%, transparent); }
.pal-empty { padding: 26px; text-align: center; color: var(--faint); font-size: 13.5px; }
.pal-foot { display: flex; gap: 14px; padding: 9px 14px; border-top: 1px solid var(--border); font-size: 11px; color: var(--faint); }

@keyframes fade { from { opacity: 0 } to { opacity: 1 } }
@keyframes pop  { from { opacity: 0; transform: translateY(-10px) scale(.98) } to { opacity: 1; transform: none } }

/* ---------- toast ---------- */

.toasts { position: fixed; bottom: 20px; left: 50%; transform: translateX(-50%); z-index: 300; display: flex; flex-direction: column; gap: 8px; align-items: center; pointer-events: none; }
.toast {
  background: var(--panel-2); border: 1px solid var(--border-strong);
  padding: 10px 16px; border-radius: 999px; font-size: 13.5px;
  box-shadow: var(--shadow-lift); animation: pop var(--t-mid) var(--ease-spring);
}

/* ---------- reveal on scroll ---------- */

.rv { opacity: 0; transform: translateY(14px); transition: opacity var(--t-slow) var(--ease-out), transform var(--t-slow) var(--ease-out); }
.rv.in { opacity: 1; transform: none; }

/* ============================================================
   HOME
   ============================================================ */

.hero { padding: clamp(56px, 11vh, 116px) 0 44px; }
.hero h1 {
  font-size: clamp(38px, 7.2vw, 82px);
  line-height: 0.98; letter-spacing: -0.035em;
  max-width: 15ch; margin: 22px 0 0;
}
.hero h1 .rot { color: var(--accent); display: inline-block; }
.hero h1 .rot span { display: inline-block; }
.hero .sub { margin: 24px 0 0; font-size: clamp(15px, 1.6vw, 18px); color: var(--text-soft); max-width: 60ch; }
.hero .cta { display: flex; flex-wrap: wrap; gap: 12px; margin-top: 30px; }
.hero .note { margin-top: 18px; font-size: 12.5px; color: var(--faint); font-family: var(--font-mono); }

.tele {
  display: grid; grid-template-columns: repeat(4, 1fr);
  border: 1px solid var(--border); border-radius: var(--radius-lg);
  background: color-mix(in srgb, var(--panel) 70%, transparent);
  overflow: hidden; margin-top: 46px;
}
.tele .cell { padding: 20px 22px; border-right: 1px solid var(--border); }
.tele .cell:last-child { border-right: 0; }
.tele .k { font-family: var(--font-mono); font-size: 10.5px; letter-spacing: .12em; text-transform: uppercase; color: var(--faint); }
.tele .v { font-family: var(--font-display); font-size: clamp(24px, 3vw, 34px); font-weight: 600; letter-spacing: -0.03em; margin-top: 6px; font-variant-numeric: tabular-nums; }
.tele .v small { font-size: 0.5em; color: var(--muted); font-weight: 400; margin-left: 4px; }
@media (max-width: 860px) { .tele { grid-template-columns: repeat(2, 1fr); } .tele .cell:nth-child(2n) { border-right: 0; } .tele .cell:nth-child(-n+2) { border-bottom: 1px solid var(--border); } }

.sec { padding: 62px 0; }
.sec-head { display: flex; align-items: flex-end; gap: 20px; flex-wrap: wrap; margin-bottom: 26px; }
.sec-head h2 { font-size: clamp(24px, 3.6vw, 38px); letter-spacing: -0.03em; }
.sec-head p { margin: 6px 0 0; color: var(--muted); font-size: 14.5px; max-width: 62ch; }
.sec-head .right { margin-left: auto; }

/* paper cards */
.papers { display: grid; grid-template-columns: 1fr 1fr; gap: 18px; }
@media (max-width: 880px) { .papers { grid-template-columns: 1fr; } }

.paper-card {
  --c: var(--p1);
  position: relative; overflow: hidden;
  padding: 26px 26px 22px;
  border: 1px solid var(--border); border-radius: var(--radius-lg);
  background:
    radial-gradient(520px 200px at 100% 0%, color-mix(in srgb, var(--c) 11%, transparent), transparent 72%),
    var(--panel);
  box-shadow: var(--shadow-soft);
  transition: border-color var(--t-mid), transform var(--t-mid) var(--ease-out), box-shadow var(--t-mid);
  display: flex; flex-direction: column;
}
.paper-card.p2 { --c: var(--p2); }
.paper-card:hover { border-color: color-mix(in srgb, var(--c) 45%, transparent); transform: translateY(-3px); box-shadow: var(--shadow-lift); }
.paper-card .pnum { font-family: var(--font-mono); font-size: 11px; letter-spacing: .16em; text-transform: uppercase; color: var(--c); }
.paper-card h3 { font-size: 25px; margin: 10px 0 6px; }
.paper-card .desc { color: var(--muted); font-size: 14px; margin: 0 0 18px; min-height: 3.2em; }
.paper-card .facts { display: flex; gap: 8px; flex-wrap: wrap; margin-bottom: 18px; }
.paper-card .bar { height: 5px; background: var(--track); border-radius: 999px; overflow: hidden; }
.paper-card .bar > i { display: block; height: 100%; width: 0; background: linear-gradient(90deg, var(--c), color-mix(in srgb, var(--c) 55%, white)); border-radius: 999px; transition: width 900ms var(--ease-out); }
.paper-card .meta { display: flex; flex-wrap: wrap; justify-content: space-between; gap: 4px 12px; margin-top: 10px; font-family: var(--font-mono); font-size: 11.5px; color: var(--muted); }
.paper-card .go { margin-top: 18px; display: flex; gap: 10px; }

/* topic strip */
.topics { display: grid; grid-template-columns: repeat(auto-fill, minmax(232px, 1fr)); gap: 10px; margin-top: 22px; }
.topic {
  display: flex; align-items: center; gap: 12px;
  padding: 13px 14px; border: 1px solid var(--border); border-radius: var(--radius);
  background: var(--tint); cursor: pointer; text-align: left; width: 100%;
  transition: all var(--t-fast);
}
.topic:hover { border-color: var(--accent); background: var(--tint-strong); transform: translateY(-2px); }
.topic .dot { width: 7px; height: 7px; border-radius: 999px; background: var(--p1); flex: none; }
.topic.p2 .dot { background: var(--p2); }
.topic .tn { flex: 1; font-size: 13.8px; }
.topic .tc { font-family: var(--font-mono); font-size: 11.5px; color: var(--faint); }
.topic .tacc { font-family: var(--font-mono); font-size: 11px; color: var(--muted); min-width: 34px; text-align: right; }

/* timeline */
.tl { position: relative; padding-left: 30px; margin-top: 12px; }
.tl::before { content: ""; position: absolute; left: 7px; top: 8px; bottom: 8px; width: 1px; background: linear-gradient(to bottom, var(--accent), color-mix(in srgb, var(--accent-2) 60%, transparent), transparent); }
.tl-item { position: relative; padding: 0 0 42px; }
.tl-item::before {
  content: ""; position: absolute; left: -27px; top: 7px;
  width: 9px; height: 9px; border-radius: 999px;
  background: var(--bg); border: 2px solid var(--accent);
}
.tl-when { font-family: var(--font-mono); font-size: 11px; letter-spacing: .12em; text-transform: uppercase; color: var(--accent); }
.tl-item h3 { font-size: 22px; margin: 8px 0 10px; }
.tl-item p { color: var(--text-soft); font-size: 14.6px; max-width: 66ch; }
.tl-note {
  margin-top: 14px; padding: 16px 18px;
  border: 1px solid var(--border); border-left: 2px solid var(--accent);
  border-radius: 0 var(--radius) var(--radius) 0;
  background: var(--tint); font-size: 14px; color: var(--text-soft);
}
.tl-note b { color: var(--text); font-family: var(--font-display); }
.tl-note .lab { display: inline-flex; align-items: center; gap: 6px; font-family: var(--font-mono); font-size: 10.5px; letter-spacing: .14em; text-transform: uppercase; color: var(--accent); margin-bottom: 8px; }

/* about */
.about { display: grid; grid-template-columns: 300px 1fr; gap: 34px; align-items: start; }
@media (max-width: 860px) { .about { grid-template-columns: 1fr; } }
.about-card { padding: 22px; text-align: center; }
.about-card .av {
  width: 62px; height: 62px; margin: 0 auto 14px; border-radius: 999px;
  display: grid; place-items: center; font-family: var(--font-display); font-size: 24px; font-weight: 600;
  background: linear-gradient(150deg, var(--accent), var(--accent-2)); color: var(--accent-ink);
}
.about-card h3 { font-size: 19px; }
.about-card .role { font-family: var(--font-mono); font-size: 11px; color: var(--muted); margin-top: 6px; letter-spacing: .04em; }
.about-card .role span { display: block; }
.about p { font-size: 15.2px; color: var(--text-soft); max-width: 70ch; }
.socials { display: flex; gap: 10px; flex-wrap: wrap; margin-top: 18px; }

/* faq */
.faq { border-top: 1px solid var(--border); }
.faq details { border-bottom: 1px solid var(--border); }
.faq summary {
  display: flex; align-items: baseline; gap: 14px;
  padding: 18px 4px; cursor: pointer; list-style: none;
  font-family: var(--font-display); font-size: 17px; font-weight: 500; letter-spacing: -0.015em;
  transition: color var(--t-fast);
}
.faq summary::-webkit-details-marker { display: none; }
.faq summary:hover { color: var(--accent); }
.faq summary .qn { font-family: var(--font-mono); font-size: 11px; color: var(--faint); flex: none; width: 22px; }
.faq summary .caret { margin-left: auto; color: var(--faint); transition: transform var(--t-mid) var(--ease-out); flex: none; }
.faq details[open] summary .caret { transform: rotate(45deg); }
.faq .ans { padding: 0 4px 22px 40px; color: var(--text-soft); font-size: 14.6px; max-width: 78ch; }
.faq .ans p:last-child { margin-bottom: 0; }
.faq .ans b { color: var(--text); }

/* callout */
.callout {
  display: flex; flex-wrap: wrap; align-items: center; gap: 18px;
  padding: 26px 28px; border-radius: var(--radius-lg);
  border: 1px solid color-mix(in srgb, var(--accent) 26%, transparent);
  background: radial-gradient(700px 200px at 10% 0%, var(--accent-soft), transparent 70%), var(--panel);
}
.callout h3 { font-size: 21px; }
.callout p { margin: 6px 0 0; color: var(--muted); font-size: 14px; }
.callout .right { margin-left: auto; display: flex; gap: 10px; flex-wrap: wrap; }

/* column vectors / small matrices */
.m .mat {
  display: inline-flex; flex-direction: column; align-items: center;
  vertical-align: middle; line-height: 1.2; margin: 0 .06em;
}
.m .mat > span { display: block; padding: 0 .18em; }

/* vector and dot accents */
.m .vecarr, .m .dotacc { position: relative; display: inline-block; }
.m .vecarr::after {
  content: "\2192"; position: absolute; left: 0; right: 0; top: -0.66em;
  font-size: .66em; line-height: 1; text-align: center; font-style: normal;
}
.m .dotacc::after {
  content: "\02D9"; position: absolute; left: 0; right: 0; top: -0.62em;
  font-size: .9em; line-height: 1; text-align: center; font-style: normal;
}
.m .dotacc.two::after { content: "\00A8"; }