/* ============================================================
   inference.eng - warm paper, editorial, motion-forward design system
   2026 patterns: scroll-triggered reveals, micro-interactions,
   GPU-accelerated transforms, prefers-reduced-motion support
   ============================================================ */

:root {
  --bg: #0a0a0f;            /* deep near-black with a hint of blue */
  --bg-2: #111118;          /* slightly lifted panel */
  --bg-3: #181822;          /* ink-wash */
  --card: #0d0d14;          /* card surface */
  --ink: #f5f5f4;           /* near-white text */
  --ink-soft: #b8b8c0;      /* soft ink */
  --muted: #6f6f7a;         /* muted gray-violet */
  --line: #1e1e2a;          /* hairline */
  --line-strong: #2c2c3a;   /* stronger line */
  --white: #ffffff;
  --black: #000000;
  --serif: "Newsreader", Georgia, serif;
  --sans: "Figtree", -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
  --mono: "Geist Mono", ui-monospace, SFMono-Regular, Menlo, Consolas, monospace;
  --radius: 12px;
  --maxw: 1680px;
  --ease: cubic-bezier(0.22, 1, 0.36, 1);
  --ease-spring: cubic-bezier(0.34, 1.56, 0.64, 1);
  --speed: 0.45s;
  --shadow: 0 1px 2px rgba(0,0,0,.4), 0 12px 40px rgba(0,0,0,.5);
  --glow: 0 0 0 1px rgba(255,255,255,.04), 0 20px 60px rgba(0,0,0,.6);
  --spotlight: radial-gradient(600px circle at var(--mx, 50%) var(--my, 0%), rgba(232, 196, 106, .07), transparent 40%);
  --accent: #e8c46a;        /* warm gold - primary accent */
  --accent-deep: #d4a94e;   /* deeper gold for emphasis */
  --accent-soft: rgba(232, 196, 106, .14); /* soft gold wash */
}

input[type="range"] { accent-color: var(--accent); }
input[type="checkbox"], input[type="radio"] { accent-color: var(--accent); }

* { box-sizing: border-box; margin: 0; padding: 0; }

html { scroll-behavior: smooth; }

body {
  font-family: var(--sans);
  background: var(--bg);
  color: var(--ink);
  line-height: 1.7;
  font-size: 16px;
  -webkit-font-smoothing: antialiased;
  overflow-x: hidden;
  position: relative;
}

/* cursor-follow spotlight over the whole page */
body::before {
  content: "";
  position: fixed;
  inset: 0;
  z-index: 0;
  pointer-events: none;
  background: radial-gradient(900px circle at var(--mx, 50%) var(--my, 0%), rgba(232,196,106,.05), transparent 45%);
  transition: opacity .4s;
}
body.spotlight-off::before { opacity: 0; }

::selection { background: var(--ink); color: var(--bg); }

/* ---------- GPU word animations ---------- */
.gpu-word {
  position: relative;
  display: inline-block;
  color: var(--ink);
  font-weight: 600;
  cursor: default;
  background: linear-gradient(90deg, transparent, rgba(255,255,255,.06), transparent);
  background-size: 200% 100%;
  animation: gpu-scan 3s ease-in-out infinite;
  border-radius: 4px;
  padding: 0 2px;
}
@keyframes gpu-scan {
  0% { background-position: -200% 0; }
  100% { background-position: 200% 0; }
}
.gpu-word::after {
  content: "";
  position: absolute; left: 0; right: 0; bottom: -2px; height: 1px;
  background: linear-gradient(90deg, transparent, var(--ink), transparent);
  opacity: .5;
  animation: gpu-line 3s ease-in-out infinite;
}
@keyframes gpu-line {
  0%, 100% { transform: scaleX(.2); opacity: .2; }
  50% { transform: scaleX(1); opacity: .6; }
}
.gpu-word:hover { animation-duration: 1.2s; }
.gpu-word:hover::after { animation-duration: 1.2s; }

/* inline term highlight */
.term {
  font-family: var(--mono);
  font-size: .92em;
  color: var(--ink);
  background: var(--bg-2);
  border: 1px solid var(--line-strong);
  border-radius: 6px;
  padding: 1px 7px;
  white-space: nowrap;
  transition: border-color .3s, box-shadow .3s, transform .3s var(--ease);
}
.term:hover {
  border-color: var(--ink);
  box-shadow: 0 0 0 1px rgba(0,0,0,.08), 0 0 24px rgba(0,0,0,.06);
  transform: translateY(-1px);
}
@media (prefers-reduced-motion: reduce) {
  .gpu-word, .gpu-word::after { animation: none !important; }
  .term { transition: none !important; }
}

/* ---------- Latest cards ---------- */
.latest-card {
  position: relative;
  background: linear-gradient(180deg, var(--card), var(--bg));
  border: 1px solid var(--line);
  border-radius: var(--radius);
  overflow: hidden;
}
.latest-card::before {
  content: "";
  position: absolute;
  top: 0; left: 0; right: 0;
  height: 2px;
  background: linear-gradient(90deg, transparent, var(--ink), transparent);
  opacity: 0.6;
}
.latest-card::after {
  content: "";
  position: absolute;
  inset: 0;
  background: radial-gradient(600px circle at var(--mx, 50%) var(--my, 0%), rgba(120,120,255,.08), transparent 40%);
  opacity: 0;
  transition: opacity .3s;
  pointer-events: none;
}
.latest-card:hover::after { opacity: 1; }
.latest-card:hover { border-color: var(--line-strong); transform: translateY(-2px); box-shadow: var(--glow); }
@media (prefers-reduced-motion: reduce) {
  .latest-card:hover { transform: none; }
  .latest-card::after { display: none; }
}

/* ---------- Manual lists ---------- */
.roadmap-list { padding-left: 1.2em; }
.roadmap-list li { margin: 10px 0; line-height: 1.6; }
.manual-list { list-style: none; padding: 0; }
.manual-list li { margin: 8px 0; padding-left: 1.2em; position: relative; }
.manual-list li::before { content: "▸"; position: absolute; left: 0; color: var(--muted); }
.manual-list a { color: var(--ink); text-decoration: none; border-bottom: 1px solid var(--line-strong); }
.manual-list a:hover { color: var(--ink); border-color: var(--ink); }

/* ---------- Sources list ---------- */
.sources { list-style: none; padding: 0; }
.sources li { margin: 8px 0; font-size: 0.92em; color: var(--muted); }
.sources a { color: var(--ink); text-decoration: underline; text-underline-offset: 3px; }
.sources a:hover { color: var(--ink-soft); }

/* ---------- SVG diagrams ---------- */
.diagram {
  margin: 28px 0;
  padding: 8px;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: var(--bg-2);
  overflow-x: auto;
}
.diagram svg {
  width: 100%;
  height: auto;
  display: block;
}
.diagram .d-node rect {
  transition: stroke .3s, filter .3s;
}
.diagram .d-node:hover rect {
  stroke: var(--ink);
  filter: drop-shadow(0 0 6px rgba(0,0,0,.12));
}
.diagram .d-node text { pointer-events: none; }
.diagram .d-arrow line, .diagram .d-arrow polygon {
  transition: stroke .3s, fill .3s;
}
.diagram .d-arrow:hover line { stroke: var(--ink); }
.diagram .d-arrow:hover polygon { fill: var(--ink); }
@media (prefers-reduced-motion: reduce) {
  .diagram .d-node rect, .diagram .d-arrow line, .diagram .d-arrow polygon { transition: none !important; }
}

/* ---------- Layout ---------- */
.wrap { max-width: var(--maxw); margin: 0 auto; padding: 0 28px; }

/* ---------- Header ---------- */
.site-header {
  position: fixed; top: 0; left: 0; right: 0; z-index: 100;
  backdrop-filter: blur(14px);
  -webkit-backdrop-filter: blur(14px);
  background: rgba(10,10,15,.72);
  border-bottom: 1px solid transparent;
  transition: border-color .4s, background .4s;
}
.site-header.scrolled { border-bottom-color: var(--line); background: rgba(10,10,15,.88); }
.site-header .wrap {
  display: flex; align-items: center; justify-content: space-between;
  height: 68px;
}
.brand {
  font-family: var(--mono); font-weight: 600; font-size: 15px;
  letter-spacing: .02em; color: var(--ink); text-decoration: none;
  display: flex; align-items: center; gap: 10px;
}
.brand .logo-mark {
  width: 28px; height: 28px; border-radius: 8px; border: 1px solid var(--line-strong);
  display: grid; place-items: center; font-size: 13px; background: var(--bg-2);
  transition: transform .3s var(--ease-spring);
}
.brand:hover .logo-mark { transform: rotate(-8deg) scale(1.08); }
.brand .dot { color: var(--ink); }

nav.main { display: flex; gap: 6px; align-items: center; }
nav.main a {
  color: var(--ink-soft); text-decoration: none; font-size: 14px;
  font-weight: 500; padding: 8px 14px; border-radius: 10px;
  transition: color .2s, background .2s;
}
nav.main a:hover { color: var(--ink); background: var(--bg-2); }
nav.main a.active { color: var(--ink); background: var(--bg-2); }

/* mobile nav */
.nav-toggle {
  display: none; background: none; border: 1px solid var(--line);
  border-radius: 10px; color: var(--ink); width: 40px; height: 40px;
  font-size: 18px; cursor: pointer;
}
@media (max-width: 720px) {
  nav.main {
    position: absolute; top: 68px; left: 0; right: 0; flex-direction: column;
    background: var(--bg); border-bottom: 1px solid var(--line);
    padding: 12px 20px 20px; gap: 4px; display: none;
  }
  nav.main.open { display: flex; }
  nav.main a { padding: 12px 14px; width: 100%; }
  .nav-toggle { display: block; }
}

/* ---------- Hero ---------- */
.hero { padding: 148px 0 72px; position: relative; }
.hero .eyebrow {
  font-family: var(--mono); font-size: 13px; color: var(--muted);
  text-transform: uppercase; letter-spacing: .14em; margin-bottom: 22px;
  display: flex; align-items: center; gap: 12px;
}
.hero .eyebrow::before { content: ""; width: 34px; height: 1px; background: var(--line-strong); }
.hero h1 {
  font-family: var(--serif); font-size: clamp(44px, 7vw, 84px);
  line-height: 1.02; font-weight: 500; letter-spacing: -.03em;
  max-width: 16ch; margin-bottom: 26px;
}
.hero h1 .accent { font-style: italic; color: var(--muted); }
.hero .lede {
  font-size: 19px; color: var(--ink-soft); max-width: 56ch; line-height: 1.65;
}
.hero .lede strong { color: var(--ink); font-weight: 600; }
.hero .cta-row { margin-top: 40px; display: flex; gap: 14px; flex-wrap: wrap; }

.btn {
  display: inline-flex; align-items: center; gap: 8px; padding: 14px 26px;
  border-radius: 999px; font-size: 14px; font-weight: 600; text-decoration: none;
  transition: transform .25s var(--ease-spring), box-shadow .25s, background .25s, border-color .25s;
  position: relative; overflow: hidden;
}
.btn::after {
  content: ""; position: absolute; inset: 0; background: rgba(0,0,0,.06);
  transform: translateX(-110%); transition: transform .5s var(--ease);
}
.btn:hover::after { transform: translateX(110%); }
.btn-primary { background: var(--ink); color: var(--bg); }
.btn-primary:hover { transform: translateY(-2px); box-shadow: var(--glow); }
.btn-ghost { border: 1px solid var(--line-strong); color: var(--ink); background: transparent; }
.btn-ghost:hover { border-color: var(--muted); background: var(--bg-2); transform: translateY(-2px); }

/* ---------- Scroll reveal ---------- */
.reveal { opacity: 0; transform: translateY(28px); transition: opacity .8s var(--ease), transform .8s var(--ease); }
.reveal.in { opacity: 1; transform: translateY(0); }
.reveal-delay-1 { transition-delay: .08s; }
.reveal-delay-2 { transition-delay: .16s; }
.reveal-delay-3 { transition-delay: .24s; }

/* ---------- Section headings ---------- */
.section-head {
  display: flex; align-items: baseline; justify-content: space-between;
  margin: 88px 0 30px; padding-top: 8px; gap: 20px;
}
.section-head h2 {
  font-family: var(--serif); font-size: 34px; font-weight: 500;
  letter-spacing: -.02em;
}
.section-head .tag {
  font-family: var(--mono); font-size: 12px; color: var(--muted);
  text-transform: uppercase; letter-spacing: .1em; white-space: nowrap;
}

/* ---------- Blog index card ---------- */
.post-list { display: flex; flex-direction: column; gap: 14px; }
.post-card {
  display: grid; grid-template-columns: 1fr auto; gap: 20px; align-items: center;
  padding: 24px 28px; background: var(--card); border: 1px solid var(--line);
  border-radius: var(--radius); text-decoration: none; color: inherit;
  transition: transform .35s var(--ease), border-color .35s, background .35s, box-shadow .35s;
  position: relative; overflow: hidden;
}
.post-card::before {
  content: ""; position: absolute; left: 0; top: 0; bottom: 0; width: 3px;
  background: var(--ink); transform: scaleY(0); transform-origin: bottom;
  transition: transform .4s var(--ease);
}
.post-card:hover { transform: translateY(-3px); border-color: var(--line-strong); background: var(--bg-2); box-shadow: var(--shadow); }
.post-card:hover::before { transform: scaleY(1); }
.post-card .meta { font-family: var(--mono); font-size: 12px; color: var(--muted); margin-bottom: 6px; }
.post-card h3 { font-family: var(--serif); font-size: 23px; font-weight: 500; margin-bottom: 6px; letter-spacing: -.01em; }
.post-card p { font-size: 15px; color: var(--ink-soft); line-height: 1.55; }
.post-card .theme {
  display: inline-block; font-family: var(--mono); font-size: 11px;
  color: var(--ink-soft); border: 1px solid var(--line);
  padding: 4px 12px; border-radius: 999px; margin-top: 10px; letter-spacing: .04em;
  transition: border-color .3s, color .3s;
}
.post-card:hover .theme { border-color: var(--line-strong); color: var(--ink); }
.post-card .arrow {
  font-size: 20px; color: var(--muted); transition: transform .35s var(--ease-spring), color .3s;
  justify-self: end;
}
.post-card:hover .arrow { transform: translateX(6px); color: var(--ink); }

/* ---------- Featured ---------- */
.featured {
  display: grid; grid-template-columns: 1.15fr .85fr; gap: 36px;
  background: var(--card); border: 1px solid var(--line); border-radius: 18px;
  padding: 40px; margin-top: 8px; position: relative; overflow: hidden;
  transition: border-color .4s, box-shadow .4s;
}
.featured:hover { border-color: var(--line-strong); box-shadow: var(--shadow); }
.featured .text h3 { font-family: var(--serif); font-size: 32px; font-weight: 500; margin: 12px 0 14px; letter-spacing: -.02em; line-height: 1.15; }
.featured .text p { color: var(--ink-soft); font-size: 16px; }
.featured .viz {
  border-radius: 14px; min-height: 220px; display: flex; align-items: center;
  justify-content: center; overflow: hidden; position: relative;
  background: radial-gradient(120% 120% at 30% 20%, #181822 0%, #0d0d14 100%);
  border: 1px solid var(--line);
}
.featured .viz svg { width: 100%; height: 100%; }
.featured .viz .float-tag {
  position: absolute; bottom: 14px; left: 14px; font-family: var(--mono);
  font-size: 11px; color: var(--ink-soft); background: rgba(10,10,15,.85);
  border: 1px solid var(--line); padding: 4px 10px; border-radius: 999px;
  backdrop-filter: blur(6px);
}

/* ---------- Journey / timeline ---------- */
.timeline { position: relative; padding: 20px 0 10px; }
.timeline::before {
  content: ""; position: absolute; left: 27px; top: 0; bottom: 0; width: 1px;
  background: linear-gradient(to bottom, transparent, var(--line-strong) 4%, var(--line-strong) 96%, transparent);
}
.tl-item { position: relative; padding: 0 0 26px 76px; }
.tl-item .tl-dot {
  position: absolute; left: 20px; top: 8px; width: 15px; height: 15px;
  border-radius: 50%; background: var(--bg); border: 2px solid var(--line-strong);
  transition: border-color .3s, background .3s, box-shadow .3s;
}
.tl-item:hover .tl-dot { border-color: var(--ink); background: var(--ink); box-shadow: 0 0 0 5px rgba(0,0,0,.05); }
.tl-item .tl-phase {
  font-family: var(--mono); font-size: 12px; color: var(--muted);
  text-transform: uppercase; letter-spacing: .12em; margin-bottom: 4px;
}
.tl-item h3 { font-family: var(--serif); font-size: 24px; font-weight: 500; margin-bottom: 6px; }
.tl-item p { color: var(--ink-soft); font-size: 15px; max-width: 62ch; }
.tl-item .tl-days { font-family: var(--mono); font-size: 12px; color: var(--muted); margin-top: 8px; }
.tl-item a.tl-link {
  display: inline-block; margin-top: 12px; font-family: var(--mono); font-size: 13px;
  color: var(--ink); text-decoration: none; border-bottom: 1px solid var(--line-strong);
  padding-bottom: 2px; transition: border-color .3s;
}
.tl-item a.tl-link:hover { border-color: var(--ink); }

/* ---------- Day grid ---------- */
.day-grid { display: grid; grid-template-columns: repeat(auto-fill, minmax(150px, 1fr)); gap: 10px; }
.day-cell {
  display: flex; flex-direction: column; gap: 4px; padding: 14px 16px;
  background: var(--card); border: 1px solid var(--line); border-radius: 12px;
  text-decoration: none; color: inherit; transition: transform .3s var(--ease), border-color .3s, background .3s;
}
.day-cell:hover { transform: translateY(-3px); border-color: var(--line-strong); background: var(--bg-2); }
.day-cell .d { font-family: var(--mono); font-size: 12px; color: var(--muted); }
.day-cell .t { font-size: 13px; color: var(--ink-soft); line-height: 1.35; }
.day-cell.done .d { color: var(--ink); }
.day-cell.done { border-color: var(--line-strong); }
.day-cell.done .t { color: var(--ink); }
.day-cell.today { border-color: var(--ink); box-shadow: 0 0 0 1px var(--ink) inset; }

/* ---------- Footer ---------- */
.site-footer {
  border-top: 1px solid var(--line); margin-top: 100px;
  padding: 36px 0; color: var(--muted); font-size: 13px;
}
.site-footer .wrap { display: flex; justify-content: space-between; flex-wrap: wrap; gap: 14px; }
.site-footer a { color: var(--ink-soft); text-decoration: none; transition: color .2s; }
.site-footer a:hover { color: var(--ink); }

/* ---------- Blog post layout ---------- */
.post-hero { padding: 148px 0 40px; }
.post-hero .eyebrow { font-family: var(--mono); font-size: 13px; color: var(--muted); text-transform: uppercase; letter-spacing: .1em; margin-bottom: 16px; display: flex; align-items: center; gap: 12px; }
.post-hero .eyebrow::before { content: ""; width: 30px; height: 1px; background: var(--line-strong); }
.post-hero h1 { font-family: var(--serif); font-size: clamp(34px, 5.4vw, 58px); line-height: 1.08; font-weight: 500; letter-spacing: -.025em; max-width: 22ch; }
.post-hero .deck { font-size: 18px; color: var(--ink-soft); max-width: 60ch; margin-top: 18px; line-height: 1.6; }
.post-hero .byline { font-family: var(--mono); font-size: 13px; color: var(--muted); margin-top: 26px; display: flex; gap: 14px; flex-wrap: wrap; align-items: center; }
.post-hero .byline .pill {
  border: 1px solid var(--line); padding: 3px 10px; border-radius: 999px; font-size: 11px;
  letter-spacing: .06em; color: var(--ink-soft);
}

article.post-body {
  max-width: 720px; margin: 0 auto; padding: 10px 28px 70px;
  font-size: 17px; color: var(--ink-soft);
}
article.post-body h2 {
  font-family: var(--serif); font-size: 30px; font-weight: 500;
  color: var(--ink); margin: 56px 0 16px; letter-spacing: -.02em; line-height: 1.2;
}
article.post-body h3 {
  font-family: var(--serif); font-size: 22px; font-weight: 500;
  color: var(--ink); margin: 36px 0 10px;
}
article.post-body p { margin: 18px 0; }
article.post-body a {
  color: var(--ink); text-decoration: underline; text-underline-offset: 3px;
  transition: color .2s;
}
article.post-body a:hover { color: var(--black); }
article.post-body strong { color: var(--ink); font-weight: 600; }
article.post-body em { color: var(--ink); }
article.post-body ul, article.post-body ol { margin: 18px 0 18px 26px; }
article.post-body li { margin: 9px 0; }
article.post-body blockquote {
  border-left: 2px solid var(--ink); background: var(--bg-2);
  padding: 20px 24px; border-radius: 0 12px 12px 0; margin: 30px 0;
}
article.post-body blockquote p { margin: 4px 0; color: var(--ink-soft); }
article.post-body blockquote .who { font-family: var(--mono); font-size: 12px; color: var(--muted); margin-top: 10px; }

/* code */
article.post-body pre {
  background: var(--bg-2); border: 1px solid var(--line);
  border-radius: 12px; padding: 20px 22px; overflow-x: auto;
  font-family: var(--mono); font-size: 13.5px; line-height: 1.65;
  margin: 26px 0;
}
article.post-body code {
  font-family: var(--mono); font-size: .9em; background: var(--bg-2);
  border: 1px solid var(--line); padding: 2px 7px; border-radius: 6px; color: var(--ink);
}
article.post-body pre code { background: none; border: none; padding: 0; color: var(--ink-soft); }

/* figures */
figure { margin: 36px 0; }
figure .fig-frame {
  background: var(--bg-2); border: 1px solid var(--line);
  border-radius: 14px; padding: 20px; overflow-x: auto;
}
figure .fig-frame svg, figure .fig-frame canvas { width: 100%; height: auto; display: block; }
figcaption {
  font-family: var(--mono); font-size: 12.5px; color: var(--muted);
  margin-top: 12px; text-align: center;
}

/* callout */
.callout {
  border: 1px solid var(--line); border-left: 2px solid var(--ink);
  background: var(--bg-2); border-radius: 0 12px 12px 0; padding: 18px 22px;
  margin: 30px 0;
}
.callout .label { font-family: var(--mono); font-size: 12px; color: var(--muted); text-transform: uppercase; letter-spacing: .08em; margin-bottom: 6px; }
.callout p { margin: 4px 0; font-size: 15px; }

/* post nav */
.post-nav {
  max-width: 720px; margin: 0 auto; padding: 36px 28px 70px;
  display: flex; justify-content: space-between; gap: 20px;
  border-top: 1px solid var(--line);
}
.post-nav a { color: var(--ink-soft); text-decoration: none; font-family: var(--mono); font-size: 14px; transition: color .2s; }
.post-nav a:hover { color: var(--ink); }

/* ---------- About page ---------- */
.about-grid { display: grid; grid-template-columns: 1.2fr .8fr; gap: 48px; padding: 20px 0 40px; }
.about-card {
  background: var(--card); border: 1px solid var(--line); border-radius: 16px;
  padding: 30px; margin-bottom: 22px; transition: border-color .3s, transform .3s var(--ease);
}
.about-card:hover { border-color: var(--line-strong); transform: translateY(-2px); }
.about-card h3 { font-family: var(--serif); font-size: 24px; font-weight: 500; margin-bottom: 14px; }
.about-card p { color: var(--ink-soft); font-size: 15.5px; margin-bottom: 10px; }
.about-card p:last-child { margin-bottom: 0; }
.about-card .stat-row { display: flex; gap: 26px; margin-top: 18px; flex-wrap: wrap; }
.about-card .stat { font-family: var(--mono); font-size: 13px; color: var(--muted); }
.about-card .stat strong { display: block; font-size: 26px; color: var(--ink); font-weight: 500; line-height: 1.1; }

/* skill chips */
.chips { display: flex; flex-wrap: wrap; gap: 8px; margin-top: 6px; }
.chip {
  font-family: var(--mono); font-size: 12px; color: var(--ink-soft);
  border: 1px solid var(--line); padding: 6px 14px; border-radius: 999px;
  transition: border-color .25s, color .25s, transform .25s var(--ease-spring);
}
.chip:hover { border-color: var(--ink); color: var(--ink); transform: translateY(-2px); }

/* day-to-day list */
.day-list { counter-reset: item; list-style: none; margin: 0; }
.day-list li {
  counter-increment: item; padding: 16px 0 16px 44px; position: relative;
  border-bottom: 1px solid var(--line); color: var(--ink-soft); font-size: 15.5px;
}
.day-list li:last-child { border-bottom: none; }
.day-list li::before {
  content: counter(item, decimal-leading-zero); position: absolute; left: 0; top: 16px;
  font-family: var(--mono); font-size: 13px; color: var(--muted);
}
.day-list li strong { color: var(--ink); }

/* ---------- Cost per token widget ---------- */
.cost-app {
  border: 1px solid var(--line); border-radius: var(--radius);
  background: var(--card); padding: 28px;
}
.cost-grid { display: grid; grid-template-columns: 1fr 1fr; gap: 40px; }
.cost-controls { display: flex; flex-direction: column; gap: 18px; }
.cost-controls label {
  display: grid; grid-template-columns: 160px 1fr auto; gap: 16px; align-items: center;
  font-family: var(--mono); font-size: 13px; color: var(--ink-soft);
}
.cost-controls select, .cost-controls input[type="range"] {
  width: 100%; background: var(--bg); border: 1px solid var(--line);
  color: var(--ink); border-radius: 8px; padding: 8px 10px; font-family: var(--mono);
  font-size: 13px;
}
.cost-controls input[type="range"] { padding: 0; }
.cost-val { font-family: var(--mono); font-size: 12px; color: var(--ink); white-space: nowrap; }
.cost-output { display: flex; flex-direction: column; gap: 14px; }
.cost-metric {
  border: 1px solid var(--line); border-radius: var(--radius); padding: 18px 22px;
  background: var(--bg); display: flex; flex-direction: column; gap: 4px;
}
.cost-label { font-family: var(--mono); font-size: 11px; color: var(--muted); text-transform: uppercase; letter-spacing: .06em; }
.cost-big { font-family: var(--serif); font-size: 40px; font-weight: 600; color: var(--ink); line-height: 1.1; }
.cost-big.accent { color: var(--accent); }
.cost-note { font-size: 13px; color: var(--muted); font-family: var(--mono); line-height: 1.5; }
@media (max-width: 820px) {
  .cost-grid { grid-template-columns: 1fr; }
  .cost-controls label { grid-template-columns: 1fr; }
}

/* ---------- Lifetime tokens widget ---------- */
.lt-grid { display: grid; grid-template-columns: 1fr 1fr; gap: 40px; }
.lt-controls { display: flex; flex-direction: column; gap: 18px; }
.lt-controls label {
  display: grid; grid-template-columns: 90px 1fr auto; gap: 16px; align-items: center;
  font-family: var(--mono); font-size: 13px; color: var(--ink-soft);
}
.lt-controls select, .lt-controls input[type="range"] {
  width: 100%; background: var(--bg); border: 1px solid var(--line);
  color: var(--ink); border-radius: 8px; padding: 8px 10px; font-family: var(--mono);
  font-size: 13px;
}
.lt-controls input[type="range"] { padding: 0; }
.lt-val { font-family: var(--mono); font-size: 12px; color: var(--ink); white-space: nowrap; }
.lt-output { display: flex; flex-direction: column; gap: 14px; }
.lt-metric {
  border: 1px solid var(--line); border-radius: var(--radius); padding: 18px 22px;
  background: var(--bg); display: flex; flex-direction: column; gap: 4px;
}
.lt-label { font-family: var(--mono); font-size: 11px; color: var(--muted); text-transform: uppercase; letter-spacing: .06em; }
.lt-big { font-family: var(--serif); font-size: 36px; font-weight: 600; color: var(--ink); line-height: 1.1; }
.lt-big.accent { color: var(--accent); }
.lt-note { font-size: 13px; color: var(--muted); font-family: var(--mono); line-height: 1.5; }
.lt-compare { font-size: 14px; color: var(--ink-soft); line-height: 1.6; }
.lt-compare strong { color: var(--ink); }
@media (max-width: 820px) {
  .lt-grid { grid-template-columns: 1fr; }
  .lt-controls label { grid-template-columns: 1fr; }
}

.reading-section { margin-top: 40px; }
.reading-section h2 { margin-bottom: 16px; }
.reading-note { color: var(--muted); font-size: 14px; margin-bottom: 20px; max-width: 720px; }
.reading-item { display: flex; gap: 16px; padding: 16px 0; border-bottom: 1px solid var(--line); }
.reading-item .cat { flex: 0 0 auto; font-family: var(--mono); font-size: 11px; text-transform: uppercase; letter-spacing: .08em; color: var(--accent); padding-top: 4px; }
.reading-item .body h3 { font-family: var(--serif); font-size: 19px; font-weight: 600; margin-bottom: 4px; }
.reading-item .body p { color: var(--muted); font-size: 15px; margin-bottom: 6px; }
.reading-item .body a { color: var(--accent); font-size: 13px; font-family: var(--mono); text-decoration: none; }
.reading-item .body a:hover { text-decoration: underline; }

/* ---------- Related posts ---------- */
.related-posts { margin-top: 48px; padding-top: 32px; border-top: 1px solid var(--line); }
.related-posts h2 { font-family: var(--serif); font-size: 28px; font-weight: 500; margin-bottom: 20px; }
.related-grid { display: grid; grid-template-columns: repeat(2, 1fr); gap: 14px; }
.related-card {
  display: block; padding: 20px 22px; background: var(--card); border: 1px solid var(--line);
  border-radius: var(--radius); text-decoration: none; color: inherit;
  transition: transform .3s var(--ease), border-color .3s, background .3s;
}
.related-card:hover { transform: translateY(-2px); border-color: var(--line-strong); background: var(--bg-2); }
.related-phase { font-family: var(--mono); font-size: 11px; color: var(--muted); text-transform: uppercase; letter-spacing: .06em; }
.related-card h3 { font-family: var(--serif); font-size: 18px; font-weight: 500; margin: 8px 0 6px; color: var(--ink); }
.related-card p { font-size: 13px; color: var(--ink-soft); line-height: 1.5; }
@media (max-width: 820px) { .related-grid { grid-template-columns: 1fr; } }

/* ---------- Decode loop widget ---------- */
.dl-controls { display: flex; gap: 24px; align-items: center; flex-wrap: wrap; margin-bottom: 12px; }
.dl-controls label { display: flex; align-items: center; gap: 10px; font-family: var(--mono); font-size: 12px; color: var(--muted); }
.dl-controls input[type="range"] { width: 120px; }
.dl-controls button {
  font-family: var(--mono); font-size: 12px; color: var(--ink); background: var(--card);
  border: 1px solid var(--line); border-radius: 999px; padding: 6px 16px; cursor: pointer;
  transition: border-color .3s, color .3s;
}
.dl-controls button:hover { border-color: var(--line-strong); }
.dl-note { font-family: var(--mono); font-size: 12px; color: var(--muted); margin-top: 10px; line-height: 1.5; }

/* ---------- Shared interactive widget controls ---------- */
/* Widget hint line under embedded playgrounds */
.widget-hint { font-family: var(--mono); font-size: 12px; color: var(--muted); margin-top: 14px; }
.widget-hint a { color: var(--accent); text-decoration: none; }
.widget-hint a:hover { text-decoration: underline; }

/* ---------- Playground widget design system ---------- */
.pg-widget { border: 1px solid var(--line); border-radius: var(--radius); background: var(--bg); padding: 24px; }
.pg-widget .pg-grid { display: grid; grid-template-columns: 260px 1fr; gap: 28px; }
.pg-widget .pg-controls { display: flex; flex-direction: column; gap: 14px; }
.pg-widget .pg-controls label {
  display: grid; grid-template-columns: 1fr auto; gap: 10px; align-items: center;
  font-family: var(--mono); font-size: 12px; color: var(--muted);
}
.pg-widget .pg-controls label span { font-family: var(--mono); font-size: 12px; color: var(--ink); }
.pg-widget .pg-controls input[type="range"], .pg-widget .pg-controls select {
  grid-column: 1 / -1; width: 100%; background: var(--card); border: 1px solid var(--line);
  color: var(--ink); border-radius: 8px; padding: 8px 10px; font-family: var(--mono); font-size: 12px;
}
.pg-widget .pg-controls input[type="range"] { padding: 0; }
.pg-widget .pg-buttons { display: flex; gap: 8px; flex-wrap: wrap; }
.pg-widget .pg-buttons button {
  font-family: var(--mono); font-size: 12px; color: var(--ink); background: var(--card);
  border: 1px solid var(--line); border-radius: 999px; padding: 6px 14px; cursor: pointer;
  transition: border-color .3s, color .3s, background .3s;
}
.pg-widget .pg-buttons button:hover { border-color: var(--accent); color: var(--accent); }
.pg-widget .pg-buttons button.primary { border-color: var(--accent); color: var(--accent); }
.pg-widget .pg-main { min-width: 0; }
.pg-widget .pg-note { font-family: var(--mono); font-size: 12px; color: var(--muted); margin-top: 12px; line-height: 1.5; }
.pg-widget .pg-metrics { display: flex; gap: 14px; flex-wrap: wrap; margin-top: 14px; }
.pg-widget .pg-metric {
  border: 1px solid var(--line); border-radius: var(--radius); padding: 10px 16px;
  background: var(--card); display: flex; flex-direction: column; gap: 2px; flex: 1 1 140px;
}
.pg-widget .pg-metric .pg-label { font-family: var(--mono); font-size: 10px; color: var(--muted); text-transform: uppercase; letter-spacing: .06em; }
.pg-widget .pg-metric .pg-big { font-family: var(--serif); font-size: 26px; font-weight: 600; color: var(--ink); line-height: 1.1; }
.pg-widget .pg-metric .pg-big.accent { color: var(--accent); }
@media (max-width: 820px) { .pg-widget .pg-grid { grid-template-columns: 1fr; } }

/* ---------- Responsive ---------- */
@media (max-width: 820px) {
  .featured { grid-template-columns: 1fr; padding: 28px; }
  .about-grid { grid-template-columns: 1fr; }
  .post-card { grid-template-columns: 1fr; gap: 12px; }
  .post-card .arrow { display: none; }
  .hero { padding-top: 120px; }
  .section-head { flex-direction: column; align-items: flex-start; gap: 6px; }
}

/* ---------- Reduced motion ---------- */
@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after {
    animation-duration: .01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: .01ms !important;
    scroll-behavior: auto !important;
  }
  .reveal { opacity: 1; transform: none; }
}