:root {
  --paper: #F6F3EC; --paper2: #ECE7DC; --paper3: #E2DCCD; --ink: #16161A; --ink2: #55555F; --ink3: #8B8B95; --line: #D8D1C2;
  --agent: #FF5A1F; --agent-soft: #FFD9C7; --agent-deep: #C23D0C; --human: #2E5BFF; --good: #0F9D58; --good-soft: #D3F2E1;
  --f-display: "Space Grotesk", system-ui, sans-serif; --f-body: "Inter", system-ui, -apple-system, sans-serif; --f-mono: "JetBrains Mono", ui-monospace, monospace;
  --r: 16px; --shadow: 6px 6px 0 rgba(22, 22, 26, .12);
}
* { box-sizing: border-box; }
html { -webkit-text-size-adjust: 100%; scroll-behavior: smooth; }
body { margin: 0; background: var(--paper); color: var(--ink); font: 400 17px/1.6 var(--f-body); -webkit-font-smoothing: antialiased; }
a { color: inherit; text-decoration-color: rgba(22,22,26,.3); text-underline-offset: 3px; }
a:hover { text-decoration-color: var(--agent); }
img, svg { max-width: 100%; }
code { font-family: var(--f-mono); font-size: .9em; background: var(--paper2); border: 1px solid var(--line); border-radius: 6px; padding: .05em .35em; }
.wrap { max-width: 1180px; margin: 0 auto; padding: 0 24px; }
.skip { position: absolute; left: -999px; } .skip:focus { left: 16px; top: 16px; background: #fff; padding: 8px 12px; z-index: 99; }
.eyebrow { font: 700 13px var(--f-mono); letter-spacing: .1em; text-transform: uppercase; color: var(--agent-deep); }
.mk { background-image: linear-gradient(transparent 60%, var(--agent-soft) 60%, var(--agent-soft) 92%, transparent 92%); }
h1, h2, h3, h4 { font-family: var(--f-display); letter-spacing: -.02em; line-height: 1.1; }

/* nav */
.nav { position: sticky; top: 0; z-index: 20; background: rgba(246, 243, 236, .92); backdrop-filter: blur(8px); border-bottom: 1px solid var(--line); }
.nav-in { display: flex; align-items: center; justify-content: space-between; height: 62px; gap: 16px; }
.brandlink { display: inline-flex; align-items: center; gap: 10px; font: 700 18px var(--f-display); letter-spacing: -.02em; text-decoration: none; color: var(--ink); }
.nav-links { display: flex; gap: 22px; font: 500 15px var(--f-body); }
.nav-links a { text-decoration: none; color: var(--ink2); } .nav-links a:hover { color: var(--ink); }
.nav-links .gh { color: var(--ink); font-weight: 600; }
@media (max-width: 640px) { .nav-links a:not(.gh):not([href="/#lessons"]) { display: none; } .brandlink span { font-size: 16px; } }

/* buttons */
.btn { display: inline-flex; align-items: center; gap: 8px; padding: 12px 20px; border: 2px solid var(--ink); border-radius: 12px; background: #fff; color: var(--ink); font: 600 16px var(--f-body); text-decoration: none; cursor: pointer; box-shadow: 4px 4px 0 var(--ink); transition: transform .08s, box-shadow .08s; }
.btn:hover { transform: translate(-1px, -1px); box-shadow: 5px 5px 0 var(--ink); }
.btn:active { transform: translate(2px, 2px); box-shadow: 1px 1px 0 var(--ink); }
.btn.primary { background: var(--agent); color: #fff; }
.btn.small { padding: 8px 13px; font-size: 14px; border-radius: 10px; box-shadow: 3px 3px 0 var(--ink); }
.btn.ghost { box-shadow: none; border-color: var(--line); background: transparent; }
.btn.ghost:hover { border-color: var(--ink); transform: none; }

/* hero */
.hero { padding: 56px 0 40px; }
.hero-in { display: grid; grid-template-columns: 1fr 1.05fr; gap: 48px; align-items: center; }
.hero h1 { font-size: clamp(42px, 6vw, 72px); margin: 14px 0 18px; letter-spacing: -.04em; line-height: 1.0; }
.lede { font-size: 19px; color: var(--ink2); margin: 0 0 26px; max-width: 620px; }
.cta { display: flex; gap: 14px; flex-wrap: wrap; }
.facts { display: flex; gap: 26px; list-style: none; padding: 0; margin: 30px 0 0; color: var(--ink2); font-size: 15px; flex-wrap: wrap; }
.facts b { display: block; font: 700 26px var(--f-display); color: var(--ink); letter-spacing: -.02em; }
.hero-play { min-width: 0; }
.mini { position: relative; width: 100%; aspect-ratio: 16 / 9; border: 2px solid var(--ink); border-radius: 18px; overflow: hidden; box-shadow: var(--shadow); background: var(--paper); }
.mini .stage { position: absolute; left: 0; top: 0; transform-origin: 0 0; }
.mini-cap { font-size: 13px; color: var(--ink3); margin: 10px 2px 0; }
@media (max-width: 900px) { .hero-in { grid-template-columns: 1fr; } .hero { padding-top: 30px; } }

.band { border-top: 1px solid var(--line); border-bottom: 1px solid var(--line); background: #fff; }
.band-in { display: grid; grid-template-columns: repeat(3, 1fr); gap: 32px; padding-top: 26px; padding-bottom: 26px; }
.band h3 { margin: 0 0 6px; font-size: 19px; } .band p { margin: 0; color: var(--ink2); font-size: 15.5px; }
@media (max-width: 760px) { .band-in { grid-template-columns: 1fr; gap: 18px; } }

/* curriculum */
.curriculum { padding: 56px 24px 20px; }
.curriculum h2, .people h2, .faq h2, .agents-teaser h2 { font-size: clamp(30px, 4vw, 42px); margin: 0 0 12px; }
.progress-line { display: flex; align-items: center; gap: 16px; color: var(--ink2); font-size: 14px; margin-bottom: 26px; }
.pbar { flex: 0 0 200px; height: 8px; border-radius: 4px; background: var(--paper3); overflow: hidden; } .pbar i { display: block; height: 100%; width: 0; background: var(--good); }
.module { display: grid; grid-template-columns: 260px 1fr; gap: 30px; padding: 26px 0; border-top: 1px solid var(--line); }
.mnum { font: 700 12px var(--f-mono); letter-spacing: .1em; text-transform: uppercase; color: var(--agent-deep); }
.mhead h3 { margin: 6px 0 6px; font-size: 24px; } .mhead p { margin: 0; color: var(--ink2); font-size: 15px; }
.lrows { display: flex; flex-direction: column; gap: 10px; }
.lrow { display: grid; grid-template-columns: 46px 1fr auto; gap: 14px; align-items: center; padding: 14px 16px; background: #fff; border: 2px solid var(--ink); border-radius: 14px; text-decoration: none; color: var(--ink); box-shadow: 3px 3px 0 rgba(22,22,26,.1); transition: transform .08s, box-shadow .08s; }
a.lrow:hover { transform: translate(-1px, -1px); box-shadow: 5px 5px 0 var(--ink); }
.lrow.soon { border-color: var(--line); background: transparent; box-shadow: none; color: var(--ink3); }
.lnum { font: 700 18px var(--f-mono); color: var(--ink3); }
.ltxt b { display: block; font: 600 17px/1.3 var(--f-display); letter-spacing: -.01em; } .ltxt i { display: block; font-style: normal; font-size: 14px; color: var(--ink2); margin-top: 3px; display: -webkit-box; -webkit-line-clamp: 2; -webkit-box-orient: vertical; overflow: hidden; }
.lrow.soon .ltxt i { color: var(--ink3); }
.lmeta { font: 500 13px var(--f-mono); color: var(--ink3); display: flex; align-items: center; gap: 10px; white-space: nowrap; }
.ldone { display: none; width: 24px; height: 24px; border-radius: 50%; background: var(--good); color: #fff; font-size: 14px; align-items: center; justify-content: center; }
.lrow.done .ldone { display: inline-flex; } .lrow.done .lnum { color: var(--good); }
@media (max-width: 760px) { .module { grid-template-columns: 1fr; gap: 14px; } .lrow { grid-template-columns: 34px 1fr; } .lmeta { grid-column: 2; } }

/* agents teaser */
.agents-teaser { display: grid; grid-template-columns: 1fr 1fr; gap: 40px; align-items: center; padding-top: 60px; padding-bottom: 30px; }
.agents-teaser p { color: var(--ink2); }
.code-card { position: relative; background: #111216; color: #ECECEF; border: 2px solid var(--ink); border-radius: 14px; padding: 18px 20px; font: 400 14.5px/1.6 var(--f-mono); white-space: pre-wrap; overflow-x: auto; box-shadow: var(--shadow); margin: 0; }
.code-card pre { margin: 0; font: inherit; white-space: pre-wrap; }
.code-card .c { color: #4ADE80; } .code-card .d { color: #7d828d; }
.code-card .copy { position: absolute; top: 10px; right: 10px; font: 700 12px var(--f-mono); background: var(--agent); color: #fff; border: 0; border-radius: 8px; padding: 6px 10px; cursor: pointer; }
.code-card.copyable pre { padding-right: 70px; }
@media (max-width: 860px) { .agents-teaser { grid-template-columns: 1fr; } }

/* people */
.people { padding-top: 60px; }
.people .sub { color: var(--ink2); margin: 0 0 18px; }
.names { display: flex; flex-wrap: wrap; gap: 8px; }
.names span { font: 500 14px var(--f-body); background: #fff; border: 1.5px solid var(--line); border-radius: 999px; padding: 5px 12px; }
.fine { font-size: 13px; color: var(--ink3); margin-top: 16px; }

/* faq */
.faq { padding-top: 56px; padding-bottom: 70px; max-width: 860px; }
.faq details { border-top: 1px solid var(--line); padding: 14px 0; }
.faq summary { cursor: pointer; font: 600 18px var(--f-display); list-style: none; }
.faq summary::before { content: "+"; display: inline-block; width: 22px; color: var(--agent); font-weight: 700; }
.faq details[open] summary::before { content: "–"; }
.faq p { color: var(--ink2); margin: 10px 0 0 22px; }

/* lesson page */
.lesson { padding-top: 22px; padding-bottom: 60px; }
.crumbs { display: flex; gap: 8px; flex-wrap: wrap; font: 500 13px var(--f-mono); color: var(--ink3); margin-bottom: 8px; }
.crumbs a { color: var(--ink2); }
.ltitle { font-size: clamp(28px, 4vw, 44px); margin: 0 0 18px; letter-spacing: -.03em; }
.player-host { min-height: 200px; }
.actions { display: flex; flex-wrap: wrap; gap: 10px; margin: 18px 0 8px; align-items: center; }
.actions .right { margin-left: auto; }
@media (max-width: 760px) { .actions .right { margin-left: 0; } }
.lgrid { display: grid; grid-template-columns: 1fr 330px; gap: 48px; margin-top: 26px; }
@media (max-width: 960px) { .lgrid { grid-template-columns: 1fr; gap: 20px; } }
.lsum { font-size: 19px; color: var(--ink2); margin: 0 0 8px; }
.lmain h2 { font-size: 26px; margin: 34px 0 12px; }
.tk { padding-left: 0; list-style: none; } .tk li { position: relative; padding-left: 30px; margin: 10px 0; }
.tk li::before { content: "✓"; position: absolute; left: 0; top: 0; color: var(--good); font-weight: 700; }
.tk em, .pr em { font-style: normal; background: var(--agent-soft); padding: 0 .15em; }
.transcript h4 { font-size: 15px; font-family: var(--f-mono); text-transform: uppercase; letter-spacing: .08em; color: var(--agent-deep); margin: 22px 0 6px; }
.tr-p { margin: 6px 0; padding: 6px 10px 6px 0; border-radius: 8px; color: var(--ink2); transition: background .2s, color .2s; }
.tr-p.on { background: #fff; color: var(--ink); box-shadow: inset 3px 0 0 var(--agent); padding-left: 10px; }
.tr-t { font: 600 12px var(--f-mono); color: var(--agent-deep); background: none; border: 0; cursor: pointer; padding: 0 10px 0 0; }
.lside section { margin-bottom: 30px; }
.lside h3 { font-size: 17px; margin: 0 0 12px; }
.srcs { list-style: none; padding: 0; margin: 0; display: flex; flex-direction: column; gap: 8px; }
.srcs a { display: block; padding: 10px 12px; border: 1.5px solid var(--line); border-radius: 10px; background: #fff; text-decoration: none; font-size: 14px; line-height: 1.35; }
.srcs a:hover { border-color: var(--ink); }
.srcs b { display: block; font-weight: 600; } .srcs span { display: block; color: var(--ink2); } .srcs i { display: block; font: 500 12px var(--f-mono); font-style: normal; color: var(--agent-deep); margin-top: 3px; }
.pr { padding-left: 18px; font-size: 14.5px; color: var(--ink2); } .pr li { margin: 6px 0; }
.more { font-size: 14px; font-weight: 600; }
.mlist { padding-left: 20px; font-size: 14.5px; } .mlist li { margin: 6px 0; } .mlist .cur a { font-weight: 700; color: var(--agent-deep); } .mlist .soon { color: var(--ink3); }
.mlist a.done::after { content: " ✓"; color: var(--good); }
.tryit p { color: var(--ink2); }
.nojs { padding: 20px; background: #fff; border-radius: 12px; }

/* player */
.player { position: relative; user-select: none; }
.pl-frame { position: relative; width: 100%; display: flex; justify-content: center; background: var(--ink); border-radius: 18px; overflow: hidden; border: 2px solid var(--ink); box-shadow: var(--shadow); cursor: pointer; }
.pl-scale { position: relative; overflow: hidden; }
.pl-scale .stage { position: absolute; left: 0; top: 0; transform-origin: 0 0; }
.pl-big { position: absolute; left: 50%; top: 50%; transform: translate(-50%, -50%); width: 92px; height: 92px; border-radius: 50%; border: 3px solid var(--ink); background: var(--agent); color: #fff; display: grid; place-items: center; cursor: pointer; box-shadow: 5px 5px 0 var(--ink); z-index: 5; transition: opacity .2s, transform .2s; }
.pl-big svg { margin-left: 6px; }
.player.is-playing .pl-big, .player.at-gate .pl-big { opacity: 0; pointer-events: none; transform: translate(-50%, -50%) scale(.8); }
.pl-gate { position: absolute; left: 50%; bottom: 14px; transform: translateX(-50%); background: var(--ink); color: #fff; font: 600 14px var(--f-body); padding: 8px 14px; border-radius: 999px; z-index: 6; pointer-events: none; }
.pl-bar { display: flex; align-items: center; gap: 12px; margin-top: 10px; padding: 8px 10px; background: #fff; border: 2px solid var(--ink); border-radius: 14px; }
.pl-bar button { background: none; border: 0; cursor: pointer; color: var(--ink); font: 700 13px var(--f-mono); padding: 6px 8px; border-radius: 8px; display: grid; place-items: center; }
.pl-bar button:hover { background: var(--paper2); }
.pl-play .ic-pause { display: none; } .player.is-playing .pl-play .ic-play { display: none; } .player.is-playing .pl-play .ic-pause { display: inline; }
.pl-time { font: 500 13px var(--f-mono); color: var(--ink2); white-space: nowrap; min-width: 92px; }
.pl-scrub { position: relative; flex: 1; height: 26px; cursor: pointer; }
.pl-scrub::before { content: ""; position: absolute; left: 0; right: 0; top: 50%; height: 6px; margin-top: -3px; border-radius: 3px; background: var(--paper3); }
.pl-fill { position: absolute; left: 0; right: 0; top: 50%; height: 6px; margin-top: -3px; border-radius: 3px; background: var(--agent); transform-origin: left; transform: scaleX(0); }
.pl-ticks i { position: absolute; top: 50%; width: 2px; height: 10px; margin-top: -5px; background: rgba(22,22,26,.25); }
.pl-knob { position: absolute; top: 50%; width: 16px; height: 16px; margin: -8px 0 0 -8px; border-radius: 50%; background: #fff; border: 3px solid var(--ink); }
.pl-tip { position: absolute; bottom: 28px; transform: translateX(-50%); background: var(--ink); color: #fff; font: 500 12px var(--f-mono); padding: 4px 8px; border-radius: 6px; white-space: nowrap; pointer-events: none; }
.pl-cc.on { background: var(--ink) !important; color: #fff !important; }
.player:fullscreen { background: #000; display: flex; flex-direction: column; justify-content: center; padding: 10px; }
.player:fullscreen .pl-frame { border-radius: 0; border: 0; }
@media (max-width: 640px) { .pl-time { display: none; } .pl-bar { gap: 4px; } .pl-orient { display: none !important; } }

/* prose pages */
.prose { max-width: 860px; padding-top: 40px; padding-bottom: 70px; }
.prose h1 { font-size: clamp(34px, 5vw, 52px); margin: 0 0 14px; letter-spacing: -.035em; }
.prose h2 { font-size: 26px; margin-top: 40px; }
.prose li { margin: 6px 0; }
.srcgrid { display: grid; grid-template-columns: repeat(auto-fill, minmax(320px, 1fr)); gap: 14px; margin-top: 26px; }
.prose .srcgrid { max-width: none; }
.srccard { display: flex; flex-direction: column; gap: 6px; padding: 16px; background: #fff; border: 1.5px solid var(--line); border-radius: 14px; text-decoration: none; font-size: 14px; }
.srccard:hover { border-color: var(--ink); }
.srccard .kind { font: 700 11px var(--f-mono); letter-spacing: .1em; text-transform: uppercase; color: var(--agent-deep); }
.srccard b { font: 600 16px/1.3 var(--f-display); } .srccard .who { color: var(--ink2); font-weight: 500; } .srccard .sum { color: var(--ink2); display: -webkit-box; -webkit-line-clamp: 3; -webkit-box-orient: vertical; overflow: hidden; } .srccard .cited { font: 600 12px var(--f-mono); color: var(--good); }
.prose:has(.srcgrid) { max-width: 1180px; }

/* footer */
.foot { border-top: 1px solid var(--line); padding: 34px 0 46px; color: var(--ink2); font-size: 14px; }
.foot-in { display: flex; justify-content: space-between; gap: 30px; flex-wrap: wrap; }
.foot p { margin: 10px 0 0; }
.foot-links { display: flex; gap: 18px; flex-wrap: wrap; align-items: flex-start; }
.toast { position: fixed; left: 50%; bottom: 26px; transform: translateX(-50%); background: var(--ink); color: #fff; padding: 10px 16px; border-radius: 10px; font: 600 14px var(--f-body); z-index: 50; }

.pl-gate.cont { pointer-events: auto; display: flex; align-items: center; gap: 12px; padding: 6px 6px 6px 16px; }
.pl-cont { font: 700 14px var(--f-body); background: var(--agent); color: #fff; border: 2px solid #fff; border-radius: 999px; padding: 7px 14px; cursor: pointer; }
.pl-end { position: absolute; inset: 0; display: none; align-items: center; justify-content: center; background: rgba(22,22,26,.55); z-index: 8; }
.player.is-done .pl-end { display: flex; }
.player.is-done .pl-big { opacity: 0; pointer-events: none; }
.pl-end-in { display: flex; flex-direction: column; align-items: center; gap: 12px; background: var(--paper); border: 2px solid var(--ink); border-radius: 16px; padding: 22px 26px; box-shadow: 6px 6px 0 var(--ink); max-width: 90%; text-align: center; }
.pl-end-in b { font: 700 20px var(--f-display); }
.pl-next { font: 700 16px var(--f-body); background: var(--agent); color: #fff; text-decoration: none; padding: 10px 16px; border-radius: 10px; border: 2px solid var(--ink); }
.pl-replay { font: 600 14px var(--f-body); background: none; border: 0; cursor: pointer; color: var(--ink2); }

/* notes (field-notes articles) */
.note .eyebrow { font: 600 13px var(--f-mono); letter-spacing: .1em; text-transform: uppercase; color: var(--agent-deep); margin: 0 0 10px; }
.note .agree { list-style: none; counter-reset: n; padding: 0; margin: 34px 0 0; display: grid; gap: 34px; }
.note .agree > li { counter-increment: n; margin: 0; padding-top: 26px; border-top: 1px solid var(--line); }
.note .agree h2 { margin: 0 0 8px; font-size: clamp(22px, 3vw, 28px); letter-spacing: -.02em; text-wrap: balance; }
.note .agree h2::before { content: counter(n, decimal-leading-zero); display: block; font: 600 14px var(--f-mono); color: var(--agent); margin-bottom: 4px; }
.note blockquote { margin: 16px 0 10px; padding: 14px 18px; background: #FFFDF8; border: 2px solid var(--ink); border-radius: 14px; box-shadow: var(--shadow); }
.note blockquote p { margin: 0 0 8px; font: 500 19px/1.45 var(--f-display); letter-spacing: -.01em; }
.note blockquote footer { font-size: 14px; color: var(--ink2); }
.note .watch { margin: 8px 0 0; font-weight: 600; }
.note .watch a { text-decoration: none; } .note .watch a:hover { color: var(--agent-deep); }
.note-cta { margin-top: 48px; padding: 24px; background: var(--paper2); border-radius: var(--r); }
.note-cta p { margin: 0 0 14px; }