@import url('https://fonts.googleapis.com/css2?family=DM+Mono:wght@400;500&family=Space+Grotesk:wght@400;500;600;700&display=swap');

:root {
  --ink: #f4f0e8;
  --muted: #9da19d;
  --dim: #686e69;
  --bg: #111311;
  --panel: #191c19;
  --panel-2: #20251f;
  --line: #303630;
  --lime: #c7f36b;
  --orange: #ff9a65;
  --blue: #81c9f5;
  --danger: #ff806b;
  --max: 1160px;
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body { margin: 0; background: var(--bg); color: var(--ink); font-family: 'Space Grotesk', system-ui, sans-serif; line-height: 1.5; }
body::before { content: ''; position: fixed; inset: 0; pointer-events: none; opacity: .18; background-image: linear-gradient(rgba(255,255,255,.025) 1px, transparent 1px), linear-gradient(90deg, rgba(255,255,255,.025) 1px, transparent 1px); background-size: 42px 42px; mask-image: linear-gradient(to bottom, black, transparent 70%); }
a { color: inherit; }
code, .eyebrow, .brand, .status-line, .header-note, .card-kicker, .card-number, .card-link, .site-footer, .lab-label, .url-display, .payload, summary { font-family: 'DM Mono', ui-monospace, monospace; }
.shell { width: min(calc(100% - 48px), var(--max)); margin-inline: auto; }
.site-header { display: flex; justify-content: space-between; align-items: center; padding: 27px 0; border-bottom: 1px solid var(--line); }
.brand { text-decoration: none; font-weight: 500; letter-spacing: -.04em; }
.brand-mark { display: inline-grid; place-items: center; width: 26px; height: 26px; margin-right: 8px; color: var(--bg); background: var(--lime); font-weight: 500; }
.header-note, .muted { color: var(--muted); font-size: .78rem; }
.hero { padding: clamp(76px, 11vw, 138px) 0 74px; max-width: 790px; }
.eyebrow { margin: 0 0 18px; color: var(--lime); font-size: .72rem; letter-spacing: .14em; }
h1, h2, h3, p { margin-top: 0; }
h1 { margin-bottom: 27px; font-size: clamp(3.25rem, 8.5vw, 7.2rem); line-height: .91; letter-spacing: -.085em; font-weight: 600; }
h1 span { color: var(--lime); }
.hero-copy { max-width: 520px; color: var(--muted); font-size: 1.06rem; }
.status-line { display: inline-flex; gap: 10px; align-items: center; margin-top: 20px; color: var(--dim); font-size: .72rem; }
.status-dot { width: 7px; height: 7px; border-radius: 50%; background: var(--lime); box-shadow: 0 0 0 4px rgba(199,243,107,.1); }
.notice { display: flex; gap: 15px; padding: 18px 20px; margin-bottom: 100px; border: 1px solid rgba(255,128,107,.36); background: rgba(255,128,107,.06); color: #d2b0a8; }
.notice p { margin: 0; font-size: .92rem; }
.notice strong { color: var(--danger); }
.notice-icon { display: grid; flex: 0 0 22px; place-items: center; height: 22px; border: 1px solid var(--danger); color: var(--danger); font-family: 'DM Mono', monospace; }
.section-heading { display: flex; justify-content: space-between; align-items: end; margin-bottom: 25px; }
.section-heading h2 { margin: 0; font-size: clamp(2rem, 4vw, 3.1rem); letter-spacing: -.07em; line-height: 1; }
.lesson-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 14px; }
.lesson-card { min-height: 355px; padding: 24px; display: flex; flex-direction: column; border: 1px solid var(--line); background: var(--panel); text-decoration: none; transition: transform .2s ease, border-color .2s ease, background .2s ease; }
.lesson-card:hover { transform: translateY(-5px); border-color: var(--accent); background: var(--panel-2); }
.lesson-card:focus-visible, .back-link:focus-visible, summary:focus-visible, button:focus-visible { outline: 2px solid var(--lime); outline-offset: 4px; }
.lesson-card--lime { --accent: var(--lime); }
.lesson-card--orange { --accent: var(--orange); }
.lesson-card--blue { --accent: var(--blue); }
.card-top { display: flex; justify-content: space-between; color: var(--accent); }
.card-number { font-size: .78rem; }
.card-arrow { font-size: 1.3rem; }
.card-kicker { margin-top: 76px; margin-bottom: 10px; color: var(--accent); font-size: .7rem; letter-spacing: .08em; text-transform: uppercase; }
.lesson-card h3 { margin-bottom: 13px; font-size: 1.55rem; letter-spacing: -.05em; }
.lesson-card p { max-width: 240px; color: var(--muted); font-size: .92rem; }
.card-link { display: flex; justify-content: space-between; margin-top: auto; padding-top: 24px; color: var(--ink); font-size: .75rem; }
.card-link span { color: var(--accent); }
.how-it-works { margin: 130px 0 90px; padding-top: 25px; border-top: 1px solid var(--line); }
.loop-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 30px; }
.loop-grid span { color: var(--dim); font: .75rem 'DM Mono', monospace; }
.loop-grid h3 { margin: 22px 0 8px; font-size: 1.1rem; }
.loop-grid p { max-width: 250px; margin: 0; color: var(--muted); font-size: .88rem; }
.site-footer { display: flex; justify-content: space-between; padding: 20px 0 28px; border-top: 1px solid var(--line); color: var(--dim); font-size: .68rem; }

/* Lesson layout */
.lesson-hero { padding: 70px 0 45px; border-bottom: 1px solid var(--line); }
.back-link { display: inline-block; margin-bottom: 58px; color: var(--muted); font: .75rem 'DM Mono', monospace; text-decoration: none; }
.back-link:hover { color: var(--ink); }
.lesson-hero h1 { max-width: 850px; margin-bottom: 18px; font-size: clamp(3.2rem, 8vw, 6.4rem); }
.lesson-hero h1 span { color: var(--accent); }
.lesson-intro { max-width: 560px; color: var(--muted); }
.lesson-main { display: grid; grid-template-columns: minmax(0, 1.35fr) minmax(270px, .65fr); gap: 54px; padding: 55px 0 90px; }
.lab-label { margin: 0 0 11px; color: var(--accent); font-size: .7rem; letter-spacing: .1em; text-transform: uppercase; }
.demo-panel { border: 1px solid var(--line); background: var(--panel); }
.demo-toolbar { display: flex; justify-content: space-between; align-items: center; gap: 10px; padding: 13px 17px; border-bottom: 1px solid var(--line); color: var(--dim); font: .68rem 'DM Mono', monospace; }
.demo-dot { display: inline-block; width: 7px; height: 7px; margin-right: 6px; border-radius: 50%; background: var(--accent); }
.demo-body { min-height: 280px; padding: 35px; }
.demo-body h2 { margin-bottom: 10px; font-size: 1.7rem; letter-spacing: -.05em; }
.demo-body p { color: var(--muted); }
.url-display, .payload { display: block; overflow-wrap: anywhere; padding: 14px; border: 1px solid var(--line); background: #101210; color: var(--accent); font-size: .76rem; }
.url-display { margin: 24px 0; color: var(--muted); }
.payload { margin: 10px 0 0; color: var(--ink); }
.payload::selection { background: var(--accent); color: var(--bg); }
.copy-row { display: flex; justify-content: flex-end; margin-top: 10px; }
button { padding: 8px 11px; border: 1px solid var(--line); background: transparent; color: var(--muted); cursor: pointer; font: .68rem 'DM Mono', monospace; }
button:hover { border-color: var(--accent); color: var(--accent); }
.answer-stack { margin-top: 30px; }
details { border-top: 1px solid var(--line); }
details:last-child { border-bottom: 1px solid var(--line); }
summary { padding: 17px 0; color: var(--ink); cursor: pointer; font-size: .78rem; list-style-position: inside; }
summary::marker { color: var(--accent); }
.answer { padding: 0 0 22px 21px; color: var(--muted); font-size: .9rem; }
.answer strong { color: var(--ink); }
.answer code { color: var(--accent); font-size: .82rem; }
.side-note { align-self: start; padding-top: 31px; }
.side-note h2 { margin: 0 0 13px; font-size: 1.15rem; letter-spacing: -.04em; }
.side-note p, .side-note li { color: var(--muted); font-size: .88rem; }
.side-note ol { padding-left: 21px; }
.side-note li { margin: 0 0 11px; padding-left: 5px; }
.side-note li::marker { color: var(--accent); font-family: 'DM Mono', monospace; }
.lesson-footer { margin-top: auto; }

@media (max-width: 720px) {
  .shell { width: min(calc(100% - 32px), var(--max)); }
  .header-note { display: none; }
  .hero { padding-top: 80px; }
  .notice { margin-bottom: 75px; }
  .section-heading { display: block; }
  .section-heading .muted { margin-top: 14px; }
  .lesson-grid, .loop-grid, .lesson-main { grid-template-columns: 1fr; }
  .lesson-card { min-height: 300px; }
  .card-kicker { margin-top: 45px; }
  .how-it-works { margin-top: 85px; }
  .loop-grid { gap: 34px; }
  .lesson-hero { padding-top: 45px; }
  .back-link { margin-bottom: 40px; }
  .lesson-main { gap: 35px; padding-top: 38px; }
  .side-note { padding-top: 0; }
  .demo-body { padding: 24px; }
}

@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after { scroll-behavior: auto !important; transition-duration: .01ms !important; animation-duration: .01ms !important; }
}