/* ==========================================================================
   The Intelligent Classroom — site styles
   Midnight ink + electric cyan, warm amber accent, light content areas.
   ========================================================================== */

:root {
  /* Palette */
  --ink: #0b1026;
  --ink-2: #131a3d;
  --ink-3: #1d2656;
  --indigo: #3b3f9e;
  --cyan: #38d6f5;          /* on dark only */
  --cyan-soft: #a5f0ff;     /* on dark only */
  --cyan-ink: #0b6d86;      /* on light: links, accents (AA on white + paper) */
  --amber: #f6b33f;         /* CTA background (ink text on top) */
  --amber-strong: #e89a17;
  --coral: #c2410c;         /* on light only */
  --paper: #f5f6fb;
  --surface: #ffffff;
  --text: #182040;
  --muted: #4a5375;
  --line: #dde1ef;
  --line-strong: #c3c9de;

  /* Tag tints (text colors meet AA on their tint) */
  --tag-gem-bg: #ece8ff;      --tag-gem: #4c2fb5;
  --tag-article-bg: #dff6fb;  --tag-article: #0b5f75;
  --tag-podcast-bg: #ffe8df;  --tag-podcast: #9a3412;
  --tag-video-bg: #ffe4ea;    --tag-video: #a3123a;
  --tag-pdf-bg: #fff1d6;      --tag-pdf: #8a4b00;
  --tag-activity-bg: #dcf7e6; --tag-activity: #146136;
  --tag-tool-bg: #e3e9ff;     --tag-tool: #2b3f9e;

  /* Type */
  --font-head: "Space Grotesk", ui-sans-serif, system-ui, -apple-system, "Segoe UI", sans-serif;
  --font-body: "Inter", ui-sans-serif, system-ui, -apple-system, "Segoe UI", Roboto, sans-serif;
  --font-mono: ui-monospace, "SFMono-Regular", Menlo, Consolas, monospace;

  --step--1: clamp(0.83rem, 0.8rem + 0.15vw, 0.9rem);
  --step-0: clamp(1rem, 0.96rem + 0.2vw, 1.0625rem);
  --step-1: clamp(1.15rem, 1.08rem + 0.35vw, 1.3rem);
  --step-2: clamp(1.35rem, 1.2rem + 0.7vw, 1.7rem);
  --step-3: clamp(1.7rem, 1.4rem + 1.4vw, 2.4rem);
  --step-4: clamp(2.1rem, 1.6rem + 2.6vw, 3.6rem);

  /* Layout */
  --wrap: 72rem;
  --wrap-narrow: 46rem;
  --gutter: clamp(1rem, 4vw, 2rem);
  --radius: 1rem;
  --radius-sm: 0.6rem;
  --shadow: 0 1px 2px rgba(11, 16, 38, 0.06), 0 8px 24px -12px rgba(11, 16, 38, 0.18);
  --shadow-lift: 0 2px 4px rgba(11, 16, 38, 0.08), 0 18px 40px -18px rgba(11, 16, 38, 0.35);
  --header-h: 4.25rem;
}

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

html {
  -webkit-text-size-adjust: 100%;
  text-size-adjust: 100%;
  scroll-behavior: smooth;
  scroll-padding-top: calc(var(--header-h) + 1rem);
}

body {
  margin: 0;
  font-family: var(--font-body);
  font-size: var(--step-0);
  line-height: 1.65;
  color: var(--text);
  background: var(--paper);
  overflow-wrap: break-word;
}

img,
picture,
iframe { display: block; max-width: 100%; }
img { height: auto; }

h1, h2, h3, h4 {
  font-family: var(--font-head);
  line-height: 1.15;
  letter-spacing: -0.015em;
  color: var(--ink);
  margin: 0 0 0.6em;
  text-wrap: balance;
}
h1 { font-size: var(--step-4); font-weight: 700; }
h2 { font-size: var(--step-3); font-weight: 700; }
h3 { font-size: var(--step-2); font-weight: 600; }
h4 { font-size: var(--step-1); font-weight: 600; }

p, ul, ol, blockquote, figure { margin: 0 0 1em; }
ul, ol { padding-left: 1.4em; }
li + li { margin-top: 0.35em; }
strong { font-weight: 650; color: var(--ink); }

a {
  color: var(--cyan-ink);
  text-decoration-thickness: 0.08em;
  text-underline-offset: 0.18em;
}
a:hover { color: var(--ink); text-decoration-thickness: 0.14em; }

:focus-visible {
  outline: 3px solid var(--amber-strong);
  outline-offset: 3px;
  border-radius: 4px;
}

.visually-hidden {
  position: absolute !important;
  width: 1px; height: 1px;
  padding: 0; margin: -1px;
  overflow: hidden;
  clip: rect(0 0 0 0);
  white-space: nowrap;
  border: 0;
}

.skip-link {
  position: absolute;
  left: 1rem; top: -4rem;
  z-index: 100;
  padding: 0.7rem 1rem;
  background: var(--amber);
  color: var(--ink);
  font-weight: 700;
  border-radius: var(--radius-sm);
  text-decoration: none;
}
.skip-link:focus { top: 0.75rem; }

.wrap {
  width: 100%;
  max-width: var(--wrap);
  margin-inline: auto;
  padding-inline: var(--gutter);
}
.wrap-narrow { max-width: calc(var(--wrap-narrow) + 2 * var(--gutter)); }

/* External-link marker */
.ext-icon {
  display: inline-block;
  width: 0.72em; height: 0.72em;
  margin-left: 0.22em;
  vertical-align: 0.02em;
  fill: none;
  stroke: currentColor;
  stroke-width: 2.4;
  stroke-linecap: round;
  stroke-linejoin: round;
}

/* ---------- Header & navigation ---------- */
.site-header {
  position: sticky;
  top: 0;
  z-index: 50;
  background: rgba(11, 16, 38, 0.96);
  border-bottom: 1px solid rgba(56, 214, 245, 0.18);
  backdrop-filter: saturate(140%) blur(8px);
}
.header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
  min-height: var(--header-h);
}
.brand {
  display: inline-flex;
  align-items: center;
  gap: 0.65rem;
  color: #fff;
  text-decoration: none;
  font-family: var(--font-head);
  font-weight: 700;
  font-size: 1.08rem;
  letter-spacing: -0.01em;
  line-height: 1.1;
}
.brand:hover { color: var(--cyan-soft); }
.brand img {
  width: 2.25rem; height: 2.25rem;
  border-radius: 0.55rem;
  box-shadow: 0 0 0 1px rgba(56, 214, 245, 0.35), 0 0 18px rgba(56, 214, 245, 0.25);
}
.brand small {
  display: block;
  font-family: var(--font-body);
  font-weight: 500;
  font-size: 0.72rem;
  letter-spacing: 0.04em;
  color: var(--cyan-soft);
  opacity: 0.9;
}

.nav-toggle {
  display: none;
  align-items: center;
  gap: 0.45rem;
  padding: 0.55rem 0.85rem;
  font: 600 0.95rem var(--font-body);
  color: #fff;
  background: transparent;
  border: 1px solid rgba(165, 240, 255, 0.4);
  border-radius: 999px;
  cursor: pointer;
}
.nav-toggle:hover { border-color: var(--cyan); }
.icon {
  width: 1.25rem; height: 1.25rem;
  fill: none;
  stroke: currentColor;
  stroke-width: 2;
  stroke-linecap: round;
}
.nav-toggle .icon-close { display: none; }
.nav-toggle[aria-expanded="true"] .icon-close { display: block; }
.nav-toggle[aria-expanded="true"] .icon-menu { display: none; }

.site-nav > ul {
  display: flex;
  align-items: center;
  gap: 0.15rem;
  margin: 0;
  padding: 0;
  list-style: none;
}
.site-nav li { margin: 0; }
.site-nav a {
  display: block;
  padding: 0.5rem 0.7rem;
  color: #e6ebff;
  font-weight: 500;
  font-size: 0.95rem;
  text-decoration: none;
  border-radius: 999px;
}
.site-nav a:hover { color: #fff; background: rgba(56, 214, 245, 0.12); }
.site-nav a[aria-current="page"],
.site-nav .is-current > .sub-wrap > a {
  color: var(--ink);
  background: var(--cyan);
}

.has-sub { position: relative; }
.sub-wrap { display: flex; align-items: center; }
.sub-toggle {
  display: inline-grid;
  place-items: center;
  width: 2rem; height: 2rem;
  margin-left: -0.15rem;
  padding: 0;
  color: #e6ebff;
  background: transparent;
  border: 0;
  border-radius: 999px;
  cursor: pointer;
}
.sub-toggle:hover { color: #fff; background: rgba(56, 214, 245, 0.12); }
.sub-toggle .icon { width: 1rem; height: 1rem; transition: transform 0.2s ease; }
.sub-toggle[aria-expanded="true"] .icon { transform: rotate(180deg); }

.submenu {
  list-style: none;
  margin: 0;
  padding: 0.5rem;
  min-width: 15rem;
  background: var(--ink-2);
  border: 1px solid rgba(56, 214, 245, 0.25);
  border-radius: var(--radius-sm);
  box-shadow: 0 20px 40px -12px rgba(0, 0, 0, 0.55);
}
.submenu a { border-radius: 0.4rem; }
.submenu a[aria-current="page"] { color: var(--ink); background: var(--cyan); }

/* Desktop dropdown */
@media (min-width: 64.01em) {
  .submenu {
    position: absolute;
    top: calc(100% + 0.4rem);
    left: 0;
  }
  .js .submenu { display: none; }
  .js .submenu.is-open { display: block; }
  /* No-JS fallback: reveal on hover/focus */
  html:not(.js) .submenu { display: none; }
  html:not(.js) .has-sub:hover .submenu,
  html:not(.js) .has-sub:focus-within .submenu { display: block; }
}

/* Mobile nav */
@media (max-width: 64em) {
  .nav-toggle { display: inline-flex; }
  .site-nav {
    position: absolute;
    top: 100%;
    left: 0; right: 0;
    max-height: calc(100vh - var(--header-h));
    overflow-y: auto;
    background: var(--ink);
    border-bottom: 1px solid rgba(56, 214, 245, 0.25);
    box-shadow: 0 24px 40px -16px rgba(0, 0, 0, 0.6);
  }
  .js .site-nav { display: none; }
  .js .site-nav.is-open { display: block; }
  .site-nav > ul {
    flex-direction: column;
    align-items: stretch;
    gap: 0.15rem;
    padding: 0.75rem var(--gutter) 1.25rem;
  }
  .site-nav a { padding: 0.75rem 0.9rem; border-radius: 0.5rem; font-size: 1rem; }
  .sub-wrap > a { flex: 1; }
  .sub-toggle { width: 2.75rem; height: 2.75rem; }
  .submenu {
    margin: 0.2rem 0 0.4rem 0.9rem;
    padding: 0.25rem 0 0.25rem 0.6rem;
    background: transparent;
    border: 0;
    border-left: 2px solid rgba(56, 214, 245, 0.35);
    border-radius: 0;
    box-shadow: none;
    min-width: 0;
  }
  .js .submenu { display: none; }
  .js .submenu.is-open { display: block; }
}

/* ---------- Hero bands ---------- */
.hero {
  position: relative;
  isolation: isolate;
  overflow: hidden;
  color: #e9eeff;
  background: var(--ink);
}
.hero-media,
.hero-media img {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
  object-fit: cover;
  z-index: -2;
}
.hero::after {
  content: "";
  position: absolute;
  inset: 0;
  z-index: -1;
  background:
    linear-gradient(90deg, rgba(11, 16, 38, 0.94) 0%, rgba(11, 16, 38, 0.82) 45%, rgba(11, 16, 38, 0.45) 100%),
    linear-gradient(0deg, rgba(11, 16, 38, 0.85) 0%, rgba(11, 16, 38, 0) 45%);
}
.hero-inner {
  padding-block: clamp(3rem, 8vw, 6.5rem) clamp(2.75rem, 7vw, 5.5rem);
  max-width: 44rem;
}
.hero-home .hero-inner { padding-block: clamp(4rem, 11vw, 8.5rem) clamp(3.5rem, 9vw, 7rem); }
.hero h1 { color: #fff; margin-bottom: 0.35em; }
.hero h1 .glow {
  color: var(--cyan-soft);
  text-shadow: 0 0 28px rgba(56, 214, 245, 0.55);
}
.hero .lede {
  font-size: var(--step-1);
  line-height: 1.5;
  color: #d5ddff;
  max-width: 38rem;
  margin-bottom: 1.6rem;
}
.eyebrow {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  margin-bottom: 1rem;
  font: 600 0.8rem/1 var(--font-body);
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--cyan-ink);
}
.hero .eyebrow { color: var(--cyan); }
.eyebrow::before {
  content: "";
  width: 1.6rem; height: 2px;
  background: currentColor;
  box-shadow: 0 0 10px currentColor;
}
.hero-actions { display: flex; flex-wrap: wrap; gap: 0.75rem; }

.breadcrumb { margin-bottom: 1rem; font-size: var(--step--1); }
.breadcrumb ol { display: flex; flex-wrap: wrap; gap: 0.35rem; list-style: none; padding: 0; margin: 0; }
.breadcrumb li { margin: 0; }
.breadcrumb li + li::before { content: "/"; margin-right: 0.35rem; color: rgba(213, 221, 255, 0.6); }
.breadcrumb a { color: var(--cyan-soft); }
.breadcrumb a:hover { color: #fff; }
.breadcrumb [aria-current] { color: #d5ddff; }

/* ---------- Buttons ---------- */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 0.45rem;
  padding: 0.72rem 1.2rem;
  font: 650 0.97rem/1.2 var(--font-body);
  text-decoration: none;
  border-radius: 999px;
  border: 2px solid transparent;
  cursor: pointer;
  transition: transform 0.15s ease, background-color 0.15s ease, box-shadow 0.15s ease;
}
.btn-primary { color: var(--ink); background: var(--amber); }
.btn-primary:hover { color: var(--ink); background: #ffc35c; transform: translateY(-1px); box-shadow: 0 8px 20px -8px rgba(246, 179, 63, 0.7); }
.btn-ghost { color: #fff; border-color: rgba(165, 240, 255, 0.55); }
.btn-ghost:hover { color: var(--ink); background: var(--cyan); border-color: var(--cyan); }
.btn-outline { color: var(--ink); border-color: var(--line-strong); background: var(--surface); }
.btn-outline:hover { color: var(--ink); border-color: var(--ink); }
.btn-sm { padding: 0.5rem 0.95rem; font-size: 0.9rem; }

/* ---------- Sections ---------- */
.section { padding-block: clamp(3rem, 7vw, 5.5rem); }
.section + .section { border-top: 1px solid var(--line); }
.section-alt { background: var(--surface); }
.section-dark {
  background:
    radial-gradient(60rem 30rem at 85% 0%, rgba(59, 63, 158, 0.55), transparent 60%),
    radial-gradient(40rem 24rem at 0% 100%, rgba(56, 214, 245, 0.14), transparent 60%),
    var(--ink);
  color: #d5ddff;
  border-top: 0 !important;
}
.section-dark h2,
.section-dark h3 { color: #fff; }
.section-dark a:not(.btn) { color: var(--cyan-soft); }
.section-dark a:not(.btn):hover { color: #fff; }
.section-dark .eyebrow { color: var(--cyan); }

.section-head { max-width: 46rem; margin-bottom: clamp(1.75rem, 4vw, 2.5rem); }
.section-head p:not(.eyebrow) { color: var(--muted); font-size: var(--step-1); line-height: 1.55; }
.section-dark .section-head p:not(.eyebrow) { color: #c3cdf5; }

.prose { max-width: var(--wrap-narrow); }
.prose > :last-child { margin-bottom: 0; }

.two-col {
  display: grid;
  gap: clamp(1.5rem, 4vw, 3rem);
  align-items: start;
}
.two-col > *,
.grid > * { min-width: 0; }
.prose a,
.embed-meta a { overflow-wrap: anywhere; }
@media (min-width: 52em) {
  .two-col { grid-template-columns: 1.15fr 1fr; }
  .two-col.media-left { grid-template-columns: 1fr 1.15fr; }
  .two-col.v-center { align-items: center; }
}

/* ---------- Cards ---------- */
.grid {
  display: grid;
  gap: clamp(1rem, 2.5vw, 1.5rem);
  grid-template-columns: repeat(auto-fill, minmax(min(100%, 16.5rem), 1fr));
}
.grid-2 { grid-template-columns: repeat(auto-fill, minmax(min(100%, 22rem), 1fr)); }
.grid-4 { grid-template-columns: repeat(auto-fit, minmax(min(100%, 14.5rem), 1fr)); }

.card {
  position: relative;
  display: flex;
  flex-direction: column;
  padding: clamp(1.25rem, 3vw, 1.6rem);
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
  transition: transform 0.18s ease, box-shadow 0.18s ease, border-color 0.18s ease;
}
.card h3 { font-size: var(--step-1); margin-bottom: 0.45em; }
.card p { color: var(--muted); }
.card > :last-child { margin-bottom: 0; }
.card .card-actions { margin-top: auto; padding-top: 0.75rem; display: flex; flex-wrap: wrap; gap: 0.5rem 1rem; align-items: center; }
.card-link { font-weight: 650; }

/* Whole-card click target */
.card-linked:hover { transform: translateY(-3px); box-shadow: var(--shadow-lift); border-color: var(--line-strong); }
.card-linked h3 a { color: var(--ink); text-decoration: none; }
.card-linked h3 a::after { content: ""; position: absolute; inset: 0; border-radius: inherit; }
.card-linked h3 a:hover { color: var(--cyan-ink); }
.card-linked:focus-within { outline: 3px solid var(--amber-strong); outline-offset: 3px; }
.card-linked h3 a:focus-visible { outline: none; }

.card-icon {
  display: grid;
  place-items: center;
  width: 2.75rem; height: 2.75rem;
  margin-bottom: 1rem;
  color: var(--cyan);
  background: linear-gradient(135deg, var(--ink-3), var(--ink));
  border-radius: 0.8rem;
  box-shadow: 0 0 0 1px rgba(56, 214, 245, 0.35), 0 6px 18px -6px rgba(56, 214, 245, 0.55);
}
.card-icon svg { width: 1.4rem; height: 1.4rem; fill: none; stroke: currentColor; stroke-width: 1.8; stroke-linecap: round; stroke-linejoin: round; }

.card-dark {
  background: linear-gradient(160deg, var(--ink-3), var(--ink-2));
  border-color: rgba(56, 214, 245, 0.22);
  color: #d5ddff;
}
.card-dark h3, .card-dark h3 a { color: #fff; }
.card-dark p { color: #c3cdf5; }

/* ---------- Tags ---------- */
.tags { display: flex; flex-wrap: wrap; gap: 0.4rem; margin-bottom: 0.85rem; }
.tag {
  display: inline-flex;
  align-items: center;
  padding: 0.22rem 0.6rem;
  font: 700 0.72rem/1.2 var(--font-body);
  letter-spacing: 0.06em;
  text-transform: uppercase;
  border-radius: 999px;
  background: var(--tag-tool-bg);
  color: var(--tag-tool);
}
.tag-gem { background: var(--tag-gem-bg); color: var(--tag-gem); }
.tag-article { background: var(--tag-article-bg); color: var(--tag-article); }
.tag-podcast { background: var(--tag-podcast-bg); color: var(--tag-podcast); }
.tag-video { background: var(--tag-video-bg); color: var(--tag-video); }
.tag-pdf { background: var(--tag-pdf-bg); color: var(--tag-pdf); }
.tag-activity { background: var(--tag-activity-bg); color: var(--tag-activity); }

/* ---------- Media / figures ---------- */
.figure { margin: 0; }
.figure img {
  width: 100%;
  border-radius: var(--radius);
  border: 1px solid var(--line);
  box-shadow: var(--shadow);
  background: var(--surface);
}
.figure figcaption { margin-top: 0.6rem; font-size: var(--step--1); color: var(--muted); }
.figure-portrait { max-width: 26rem; }

/* Click-to-load embeds */
.embed {
  position: relative;
  aspect-ratio: var(--ratio, 16 / 9);
  overflow: hidden;
  background: var(--ink);
  border-radius: var(--radius);
  box-shadow: var(--shadow-lift);
}
.embed iframe { position: absolute; inset: 0; width: 100%; height: 100%; border: 0; }
.embed-facade {
  position: absolute;
  inset: 0;
  display: block;
  color: #fff;
  text-decoration: none;
}
.embed-facade picture,
.embed-facade img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  transition: transform 0.4s ease, filter 0.3s ease;
}
.embed-contain .embed-facade img { object-fit: contain; background: var(--ink); }
.embed-top .embed-facade img { object-position: top; }
.embed-facade::after {
  content: "";
  position: absolute;
  inset: 0;
  background: linear-gradient(0deg, rgba(11, 16, 38, 0.88) 0%, rgba(11, 16, 38, 0.1) 55%, rgba(11, 16, 38, 0.15) 100%);
}
.embed-facade:hover img { transform: scale(1.03); filter: brightness(1.05); }
.embed-play {
  position: absolute;
  z-index: 1;
  top: 50%; left: 50%;
  display: grid;
  place-items: center;
  width: 4.25rem; height: 4.25rem;
  transform: translate(-50%, -60%);
  color: var(--ink);
  background: var(--amber);
  border-radius: 50%;
  box-shadow: 0 0 0 8px rgba(246, 179, 63, 0.25), 0 10px 30px rgba(0, 0, 0, 0.45);
  transition: transform 0.2s ease, box-shadow 0.2s ease;
}
.embed-play svg { width: 1.6rem; height: 1.6rem; fill: currentColor; }
.embed-facade:hover .embed-play,
.embed-facade:focus-visible .embed-play { transform: translate(-50%, -60%) scale(1.08); box-shadow: 0 0 0 12px rgba(246, 179, 63, 0.3), 0 10px 30px rgba(0, 0, 0, 0.45); }
.embed-label {
  position: absolute;
  z-index: 1;
  left: 1rem; right: 1rem; bottom: 0.9rem;
  font: 600 0.95rem/1.3 var(--font-head);
  text-shadow: 0 1px 8px rgba(0, 0, 0, 0.6);
}
.embed-label small {
  display: block;
  margin-bottom: 0.2rem;
  font: 700 0.7rem/1 var(--font-body);
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--cyan-soft);
}
.embed-facade:focus-visible { outline: 3px solid var(--amber); outline-offset: -3px; border-radius: var(--radius); }
.embed-art {
  position: absolute;
  inset: 0;
  display: flex;
  align-items: flex-start;
  justify-content: center;
  padding: 1.25rem 1.5rem 0;
  text-align: center;
  font: 700 clamp(1.1rem, 3.5vw, 1.6rem)/1.2 var(--font-head);
  color: #fff;
}
.embed-meta {
  display: flex;
  flex-wrap: wrap;
  gap: 0.4rem 1.1rem;
  margin: 0.75rem 0 0;
  font-size: var(--step--1);
  color: var(--muted);
}
.embed-meta a { font-weight: 650; }
.section-dark .embed-meta { color: #c3cdf5; }
.embed-portrait { --ratio: 9 / 16; max-width: 22rem; }
.embed-doc { --ratio: 4 / 5; max-width: 30rem; }
.embed-doc-wide { --ratio: 4 / 3; }

/* ---------- Activity cards & steps ---------- */
.activity {
  position: relative;
  padding: clamp(1.4rem, 4vw, 2.25rem);
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: calc(var(--radius) + 0.25rem);
  box-shadow: var(--shadow);
}
.activity + .activity { margin-top: clamp(1.25rem, 3vw, 2rem); }
.activity::before {
  content: "";
  position: absolute;
  left: -1px; top: 1.6rem; bottom: 1.6rem;
  width: 4px;
  border-radius: 0 4px 4px 0;
  background: linear-gradient(180deg, var(--cyan), var(--indigo));
}
.activity-num {
  display: inline-block;
  margin-bottom: 0.6rem;
  font: 700 0.78rem/1 var(--font-body);
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--muted);
}
.activity h2,
.activity h3 { font-size: var(--step-2); }
.activity .subtitle { font-size: var(--step-1); color: var(--muted); line-height: 1.5; }
.activity > :last-child { margin-bottom: 0; }
.activity .label {
  margin: 1.4rem 0 0.5rem;
  font: 700 0.8rem/1.2 var(--font-body);
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--cyan-ink);
}
.activity-actions { display: flex; flex-wrap: wrap; gap: 0.6rem; margin-top: 1.25rem; }

.steps {
  counter-reset: step;
  list-style: none;
  padding: 0;
  margin: 1.25rem 0;
}
.steps > li {
  counter-increment: step;
  position: relative;
  padding: 0.1rem 0 0 3rem;
  margin: 0;
  min-height: 2.2rem;
}
.steps > li + li { margin-top: 1rem; }
.steps > li::before {
  content: counter(step);
  position: absolute;
  left: 0; top: 0;
  display: grid;
  place-items: center;
  width: 2.1rem; height: 2.1rem;
  font: 700 0.95rem/1 var(--font-head);
  color: var(--ink);
  background: linear-gradient(135deg, var(--cyan-soft), var(--cyan));
  border-radius: 50%;
  box-shadow: 0 0 0 4px rgba(56, 214, 245, 0.15);
}
.steps ul { margin-top: 0.6rem; }

.rounds { list-style: none; padding: 0; margin: 1rem 0; display: grid; gap: 0.6rem; }
.rounds li {
  margin: 0;
  padding: 0.75rem 1rem;
  background: var(--paper);
  border: 1px solid var(--line);
  border-radius: var(--radius-sm);
}
.code {
  display: inline-block;
  min-width: 3.4rem;
  margin-right: 0.35rem;
  padding: 0.12rem 0.45rem;
  font: 700 0.82rem/1.4 var(--font-mono);
  text-align: center;
  color: #fff;
  background: var(--ink-3);
  border-radius: 0.35rem;
}

.callout {
  margin: 1.25rem 0;
  padding: 1rem 1.15rem;
  background: #eefbfe;
  border: 1px solid #bfeaf5;
  border-left: 4px solid var(--cyan-ink);
  border-radius: var(--radius-sm);
}
.callout > :last-child { margin-bottom: 0; }
.callout-warm { background: #fff7e8; border-color: #f6dca8; border-left-color: var(--amber-strong); }

/* ---------- Prompt / code blocks ---------- */
.prompt {
  position: relative;
  margin: 1.25rem 0;
  background: var(--ink);
  color: #e3e9ff;
  border: 1px solid rgba(56, 214, 245, 0.3);
  border-radius: var(--radius);
  box-shadow: var(--shadow-lift);
  overflow: hidden;
}
.prompt-head {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 0.75rem;
  padding: 0.65rem 0.75rem 0.65rem 1.1rem;
  background: var(--ink-2);
  border-bottom: 1px solid rgba(56, 214, 245, 0.2);
}
.prompt-title {
  margin: 0;
  font: 700 0.78rem/1.3 var(--font-body);
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--cyan);
}
.prompt-body {
  padding: 1.1rem 1.25rem 1.3rem;
  font-size: 0.97rem;
  line-height: 1.65;
}
.prompt-body p { margin-bottom: 0.85em; }
.prompt-body > :last-child { margin-bottom: 0; }
.prompt-body strong { color: #fff; }
.copy-btn {
  flex-shrink: 0;
  white-space: nowrap;
  display: inline-flex;
  align-items: center;
  gap: 0.4rem;
  padding: 0.4rem 0.8rem;
  font: 650 0.85rem/1.2 var(--font-body);
  color: var(--ink);
  background: var(--cyan);
  border: 0;
  border-radius: 999px;
  cursor: pointer;
}
.copy-btn:hover { background: var(--cyan-soft); }
.copy-btn svg { width: 1rem; height: 1rem; fill: none; stroke: currentColor; stroke-width: 2; stroke-linecap: round; stroke-linejoin: round; }
.copy-btn[hidden] { display: none; }

.quote-list { list-style: none; padding: 0; }
.quote-list li { padding-left: 1rem; border-left: 3px solid var(--line-strong); }
.quote-list li + li { margin-top: 0.75rem; }

.exemplar {
  padding: clamp(1.25rem, 3vw, 2rem);
  background: var(--paper);
  border: 1px dashed var(--line-strong);
  border-radius: var(--radius);
}
.exemplar h3 { font-size: var(--step-1); margin-top: 1.75rem; }
.exemplar h3:first-child { margin-top: 0; }
.exemplar h4 {
  margin: 1rem 0 0.5rem;
  font: 700 0.9rem/1.3 var(--font-body);
  letter-spacing: 0.02em;
  color: var(--cyan-ink);
}
.exemplar > :last-child { margin-bottom: 0; }

/* ---------- Page TOC ---------- */
.toc {
  margin-top: 1.75rem;
}
.toc ul {
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem;
  list-style: none;
  margin: 0;
  padding: 0;
}
.toc li { margin: 0; }
.toc a {
  display: inline-block;
  padding: 0.45rem 0.9rem;
  font-size: 0.9rem;
  font-weight: 600;
  color: #e6ebff;
  text-decoration: none;
  background: rgba(255, 255, 255, 0.06);
  border: 1px solid rgba(165, 240, 255, 0.3);
  border-radius: 999px;
}
.toc a:hover { color: var(--ink); background: var(--cyan); border-color: var(--cyan); }

/* ---------- LLM list ---------- */
.llm-list { list-style: none; padding: 0; display: grid; gap: 0.75rem; }
.llm-list li {
  margin: 0;
  display: grid;
  grid-template-columns: minmax(8.5rem, auto) 1fr;
  gap: 0.25rem 1rem;
  align-items: baseline;
  padding: 0.9rem 1.1rem;
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: var(--radius-sm);
}
.llm-list a { font: 700 1.05rem/1.3 var(--font-head); }
.llm-list span { color: var(--muted); }
@media (max-width: 30em) { .llm-list li { grid-template-columns: 1fr; } }

.check-list { list-style: none; padding: 0; }
.check-list li { position: relative; padding-left: 1.8rem; }
.check-list li::before {
  content: "";
  position: absolute;
  left: 0; top: 0.42em;
  width: 1.05rem; height: 1.05rem;
  border-radius: 50%;
  background: var(--cyan-ink) url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 24 24' fill='none' stroke='white' stroke-width='3.5' stroke-linecap='round' stroke-linejoin='round'%3E%3Cpath d='M5 12.5l4.5 4.5L19 7.5'/%3E%3C/svg%3E") center / 70% no-repeat;
}

.profile {
  display: grid;
  gap: 1rem;
  padding: clamp(1.25rem, 3vw, 2rem);
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
}
.profile dl { display: grid; grid-template-columns: auto 1fr; gap: 0.35rem 1rem; margin: 0; }
.profile dt { font-weight: 700; color: var(--ink); }
.profile dd { margin: 0; }
.profile blockquote {
  margin: 0;
  padding: 1rem 1.15rem;
  background: var(--paper);
  border-left: 4px solid var(--indigo);
  border-radius: 0 var(--radius-sm) var(--radius-sm) 0;
}
.profile blockquote p { margin: 0.35rem 0 0; }

/* ---------- About ---------- */
.contact-panel {
  padding: clamp(1.4rem, 3vw, 2rem);
  border-radius: var(--radius);
  background: linear-gradient(160deg, var(--ink-3), var(--ink));
  color: #d5ddff;
  box-shadow: var(--shadow-lift);
}
.contact-panel h2, .contact-panel h3 { color: #fff; }
.contact-panel a:not(.btn) { color: var(--cyan-soft); }
.contact-panel a:not(.btn):hover { color: #fff; }
.pull {
  font: 700 var(--step-3)/1.15 var(--font-head);
  color: var(--ink);
  letter-spacing: -0.02em;
}
.pull span { color: var(--cyan-ink); }
.sticky-col { position: sticky; top: calc(var(--header-h) + 1.5rem); }
@media (max-width: 52em) { .sticky-col { position: static; } }

/* ---------- Footer ---------- */
.site-footer {
  color: #c3cdf5;
  background: var(--ink);
  border-top: 1px solid rgba(56, 214, 245, 0.2);
  padding-block: clamp(2.5rem, 6vw, 3.5rem) 1.5rem;
  font-size: 0.95rem;
}
.footer-grid {
  display: grid;
  gap: 2rem;
}
@media (min-width: 48em) {
  .footer-grid { grid-template-columns: 1.3fr 2fr; }
}
.footer-brand .brand { margin-bottom: 0.9rem; }
.footer-brand p { max-width: 26rem; }
.site-footer a { color: var(--cyan-soft); }
.site-footer a:hover { color: #fff; }
.footer-nav ul {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(10rem, 1fr));
  gap: 0.35rem 1.25rem;
  list-style: none;
  margin: 0;
  padding: 0;
}
.footer-nav li { margin: 0; }
.footer-nav a { color: #e6ebff; text-decoration: none; }
.footer-nav a:hover { color: var(--cyan); text-decoration: underline; }
.footer-heading {
  margin-bottom: 0.75rem;
  font: 700 0.78rem/1.2 var(--font-body);
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--cyan);
}
.footer-bottom {
  display: flex;
  flex-wrap: wrap;
  justify-content: space-between;
  gap: 0.5rem 1.5rem;
  margin-top: 2.25rem;
  padding-top: 1.25rem;
  border-top: 1px solid rgba(165, 240, 255, 0.15);
  font-size: 0.88rem;
}
.footer-bottom p { margin: 0; }

/* ---------- Utilities ---------- */
.mt-0 { margin-top: 0; }
.mb-0 { margin-bottom: 0; }
.muted { color: var(--muted); }
.small { font-size: var(--step--1); }
.center { text-align: center; }
.stack > * + * { margin-top: clamp(1.5rem, 4vw, 2.5rem); }
.inline-links { display: flex; flex-wrap: wrap; gap: 0.5rem 1.25rem; }

/* ---------- Motion ---------- */
@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  *,
  *::before,
  *::after {
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
  }
  .card-linked:hover,
  .btn-primary:hover,
  .embed-facade:hover img { transform: none; }
}

@media print {
  .site-header, .site-footer, .skip-link, .copy-btn, .embed-play { display: none !important; }
  .hero { color: #000; background: none; }
  .hero::after, .hero-media { display: none; }
  .hero h1, .hero .lede { color: #000; }
}

/* ---------- Featured "Latest work" card (Deep Thoughts) ---------- */
.feature-card {
  display: grid;
  grid-template-columns: minmax(0, 0.8fr) minmax(0, 1.2fr);
  gap: clamp(1.5rem, 4vw, 3rem);
  align-items: center;
  padding: clamp(1.25rem, 3.5vw, 2.5rem);
  border-radius: calc(var(--radius) * 1.5);
  background: radial-gradient(120% 140% at 100% 0%, var(--ink-3) 0%, var(--ink-2) 45%, var(--ink) 100%);
  color: #dfe5ff;
  box-shadow: var(--shadow-lift);
  border: 1px solid rgba(56, 214, 245, 0.25);
}
.feature-card .eyebrow { color: var(--cyan); }
.feature-card h2 { color: #fff; font-size: var(--step-3); margin-top: 0.5rem; }
.feature-card h2 a { color: #fff; text-decoration-color: rgba(56, 214, 245, 0.6); }
.feature-card h2 a:hover { color: var(--cyan-soft); }
.feature-card p { color: #c9d2f5; }
.feature-card .feature-lede { font-size: var(--step-1); line-height: 1.5; color: #fff; }
.feature-card .feature-tag { background: rgba(255, 255, 255, 0.1); color: var(--cyan-soft); }
.feature-card :focus-visible { outline-color: var(--cyan); }
.feature-media img {
  display: block; width: 100%; height: auto; max-height: 30rem; object-fit: cover; object-position: top;
  border-radius: var(--radius); border: 1px solid rgba(255, 255, 255, 0.12);
}
@media (max-width: 52em) {
  .feature-card { grid-template-columns: 1fr; }
  .feature-media img { max-height: 18rem; }
}