/* The Left Half-Plane · one dark world for the games. Single theme on purpose. */
:root {
  --bg: #0b0c10; --bg2: #10121a; --bg3: #161a25; --line: #232838;
  --ink: #e8ebf2; --dim: #8b93a7; --faint: #4b5468;
  --blue: #9fb4e0; --amber: #f0b46a; --warm: #f4f0e6; --good: #8fd0a0; --bad: #e08a7a;
  --serif: "Newsreader", Georgia, "Times New Roman", serif;
  --display: "Marcellus", Georgia, serif;
  --mono: "IBM Plex Mono", ui-monospace, Menlo, Consolas, monospace;
}
html { background: var(--bg); color-scheme: dark; }
body { margin: 0; background: var(--bg); color: var(--ink); font-family: var(--serif); font-size: 17px; line-height: 1.6; -webkit-font-smoothing: antialiased; }
* { box-sizing: border-box; }
.wrap { max-width: 1040px; margin: 0 auto; padding: 0 24px; }
.prose { max-width: 680px; }
p { margin: 0 0 18px; max-width: 65ch; }
a { color: var(--blue); text-decoration: none; border-bottom: 1px solid var(--faint); transition: color .2s, border-color .2s; }
a:hover { color: var(--warm); border-color: var(--warm); }
::selection { background: rgba(240,180,106,.35); }
strong { font-weight: 500; color: var(--warm); }
em { font-style: italic; }
code { font-family: var(--mono); font-size: .88em; color: var(--warm); }
.math { font-family: Georgia, "Times New Roman", serif; font-style: italic; color: var(--warm); white-space: nowrap; }
.eyebrow { font-family: var(--mono); font-size: 11px; letter-spacing: .22em; text-transform: uppercase; color: var(--dim); }

/* top bar */
.top { display: flex; justify-content: space-between; align-items: center; height: 58px; border-bottom: 1px solid var(--line); }
.top .mark { font-family: var(--display); letter-spacing: .18em; text-transform: uppercase; font-size: 13px; color: var(--ink); border: 0; }
.top nav { display: flex; gap: 22px; font-family: var(--mono); font-size: 11px; letter-spacing: .14em; text-transform: uppercase; }
.top nav a { color: var(--dim); border: 0; }
.top nav a:hover { color: var(--warm); }

/* hero (hub) */
.hero { text-align: center; padding: 64px 0 24px; }
.wordmark { font-family: var(--display); font-weight: 400; font-size: clamp(1.7rem, 5.2vw, 3.9rem); letter-spacing: .3em; margin: 16px 0 14px .3em; line-height: 1.15; color: var(--ink); text-wrap: balance; }
.sentence { font-family: var(--mono); font-size: 12px; letter-spacing: .28em; margin-left: .28em; text-transform: uppercase; color: var(--dim); text-wrap: balance; }
.lede { font-size: 19px; max-width: 34em; margin: 26px auto 0; color: var(--ink); text-wrap: balance; }
.hero-stage { border: 1px solid var(--line); background: var(--bg2); margin: 34px 0 0; }
.hero-stage canvas { display: block; width: 100%; aspect-ratio: 960 / 300; touch-action: pan-y; cursor: crosshair; }

section { padding: 52px 0; border-top: 1px solid var(--line); }
h1 { font-family: var(--display); font-weight: 400; font-size: clamp(2rem, 4.6vw, 2.9rem); letter-spacing: .05em; line-height: 1.15; margin: 8px 0 14px; text-wrap: balance; }
h2 { font-family: var(--display); font-weight: 400; font-size: 28px; letter-spacing: .04em; line-height: 1.2; margin: 10px 0 20px; text-wrap: balance; }
h3 { font-family: var(--display); font-weight: 400; font-size: 20px; letter-spacing: .04em; margin: 30px 0 10px; }
.aphorism { font-style: italic; color: var(--dim); font-size: 19px; margin-top: 8px; }

/* game head */
.game-head { padding: 44px 0 22px; }
.game-head .lede { margin: 6px 0 0; text-align: left; font-size: 18px; color: var(--dim); }
.strip { font-family: var(--mono); font-size: 11.5px; color: var(--dim); display: flex; gap: 18px; flex-wrap: wrap; letter-spacing: .04em; margin: 0 0 12px; }
.strip b { color: var(--ink); font-weight: 500; font-variant-numeric: tabular-nums; }
.strip b.amber { color: var(--amber); }

/* instrument */
.instrument { display: grid; grid-template-columns: minmax(0, 1fr) 256px; border: 1px solid var(--line); background: var(--bg2); }
.stage { position: relative; min-width: 0; }
.stage canvas { display: block; width: 100%; aspect-ratio: 960 / 340; touch-action: none; cursor: crosshair; }
.stage canvas.pan { touch-action: pan-y; }
.rail { border-left: 1px solid var(--line); padding: 16px 18px; display: flex; flex-direction: column; gap: 12px; font-family: var(--mono); font-size: 12px; }
.howto { font-family: var(--mono); font-size: 11.5px; letter-spacing: .04em; color: var(--dim); margin: 0; line-height: 1.55; }
.howto b { color: var(--amber); font-weight: 500; }
.knob { display: grid; grid-template-columns: 1fr auto; gap: 0 10px; align-items: center; }
.knob .k-name { color: var(--dim); font-size: 11px; letter-spacing: .06em; }
.knob output { color: var(--amber); font-variant-numeric: tabular-nums; text-align: right; font-size: 12px; }
.knob input { grid-column: 1 / -1; width: 100%; }
input[type=range] { -webkit-appearance: none; appearance: none; height: 18px; background: transparent; margin: 0; cursor: pointer; }
input[type=range]::-webkit-slider-runnable-track { height: 2px; background: var(--line); }
input[type=range]::-webkit-slider-thumb { -webkit-appearance: none; width: 12px; height: 12px; border-radius: 50%; background: var(--amber); margin-top: -5px; border: 0; }
input[type=range]::-moz-range-track { height: 2px; background: var(--line); }
input[type=range]::-moz-range-thumb { width: 12px; height: 12px; border-radius: 50%; background: var(--amber); border: 0; }
input[type=range]:disabled { cursor: default; }
input[type=range]:disabled::-webkit-slider-thumb { background: var(--faint); }
input[type=range]:disabled::-moz-range-thumb { background: var(--faint); }
input[type=range]:focus-visible { outline: 1px solid var(--blue); outline-offset: 4px; }
.readouts { display: grid; grid-template-columns: 1fr 1fr; gap: 8px 12px; padding-top: 10px; border-top: 1px solid var(--line); }
.readouts div { display: flex; flex-direction: column; gap: 1px; min-width: 0; }
.readouts span { color: var(--dim); font-size: 10px; letter-spacing: .1em; text-transform: uppercase; }
.readouts b { font-weight: 500; font-size: 15px; color: var(--ink); font-variant-numeric: tabular-nums; white-space: nowrap; }
.readouts b.amber { color: var(--amber); }
.metrics { border-collapse: collapse; width: 100%; font-family: var(--mono); font-size: 11.5px; border-top: 1px solid var(--line); }
.metrics th { font-weight: 400; color: var(--dim); font-size: 10px; letter-spacing: .1em; text-transform: uppercase; text-align: right; padding: 8px 0 4px; }
.metrics th:first-child { text-align: left; }
.metrics td { padding: 3px 0; text-align: right; font-variant-numeric: tabular-nums; color: var(--ink); }
.metrics td:first-child { text-align: left; color: var(--dim); }
.metrics td.blue { color: var(--blue); }
.metrics td.amber { color: var(--amber); }
.buttons { display: flex; gap: 8px; flex-wrap: wrap; }
.btn { font-family: var(--mono); font-size: 11.5px; letter-spacing: .08em; text-transform: uppercase; background: transparent; color: var(--ink); border: 1px solid var(--faint); padding: 8px 12px; cursor: pointer; }
.btn:hover { border-color: var(--ink); }
.btn.primary { background: var(--amber); color: #1a1408; border-color: var(--amber); font-weight: 500; }
.btn.primary:hover { background: var(--warm); border-color: var(--warm); }
.btn:disabled { opacity: .4; cursor: default; }
.btn:focus-visible { outline: 1px solid var(--blue); outline-offset: 3px; }
.submission { font-family: var(--mono); font-size: 11px; color: var(--faint); word-break: break-word; border-top: 1px solid var(--line); padding-top: 10px; line-height: 1.55; margin-top: auto; }
.submission b { color: var(--dim); font-weight: 400; }
.caption { font-size: 15.5px; color: var(--dim); max-width: 72ch; margin: 16px 0 0; line-height: 1.6; }
.caption em { color: var(--ink); }
@media (max-width: 860px) { .instrument { grid-template-columns: 1fr; } .rail { border-left: 0; border-top: 1px solid var(--line); } }

/* the ladder: references and you */
.after { display: grid; grid-template-columns: minmax(0, 1fr) minmax(0, 1fr); gap: 24px 40px; margin-top: 22px; align-items: start; }
.ladder { font-family: var(--mono); font-size: 12px; border-top: 1px solid var(--line); }
.ladder .lrow { display: grid; grid-template-columns: minmax(0, 1.4fr) minmax(0, 1fr) 64px; gap: 12px; align-items: center; padding: 8px 0; border-bottom: 1px solid var(--line); color: var(--dim); }
.ladder .lrow.you { color: var(--amber); }
.ladder .lbar { height: 6px; background: var(--bg3); position: relative; }
.ladder .lbar i { display: block; height: 100%; background: var(--dim); }
.ladder .you .lbar i { background: var(--amber); }
.ladder .lval { text-align: right; font-variant-numeric: tabular-nums; color: var(--ink); }
.ladder .you .lval { color: var(--amber); }
.ladder .lnote { font-size: 10px; letter-spacing: .12em; text-transform: uppercase; color: var(--faint); padding: 8px 0 0; }
.ladder-title { font-family: var(--mono); font-size: 10.5px; letter-spacing: .16em; text-transform: uppercase; color: var(--faint); margin: 0 0 8px; }
@media (max-width: 720px) { .after { grid-template-columns: 1fr; } }

/* explainers */
.explain { max-width: 680px; }
.explain h2 { margin-top: 0; }
.explain h3 { margin-top: 28px; }
.explain p { color: var(--ink); }
.eq { font-family: Georgia, "Times New Roman", serif; font-style: italic; color: var(--warm); font-size: 18px; padding: 14px 18px; margin: 6px 0 20px; border-left: 2px solid var(--amber); background: var(--bg2); line-height: 1.7; overflow-x: auto; white-space: nowrap; }
.eq small { font-family: var(--mono); font-style: normal; font-size: 11px; color: var(--dim); letter-spacing: .08em; display: block; margin-top: 4px; white-space: normal; }
.next { display: flex; justify-content: space-between; gap: 20px; flex-wrap: wrap; font-family: var(--mono); font-size: 11.5px; letter-spacing: .1em; text-transform: uppercase; padding: 26px 0 0; border-top: 1px solid var(--line); margin-top: 40px; }
.next a { border: 0; color: var(--dim); }
.next a:hover { color: var(--warm); }

/* hub: series list */
.series { list-style: none; padding: 0; margin: 0; border-top: 1px solid var(--line); }
.series li { display: grid; grid-template-columns: 52px 120px minmax(0, 1fr); gap: 6px 22px; padding: 24px 0; border-bottom: 1px solid var(--line); align-items: start; }
.series .num { font-family: var(--mono); font-size: 12px; color: var(--faint); padding-top: 8px; letter-spacing: .1em; }
.series .icon { width: 120px; height: 72px; border: 1px solid var(--line); background: var(--bg2); }
.series .icon svg { display: block; width: 100%; height: 100%; }
.series .name { font-family: var(--display); font-size: 24px; letter-spacing: .04em; }
.series .name a { color: var(--ink); border: 0; }
.series .name a:hover { color: var(--amber); }
.series .name small { font-family: var(--mono); font-size: 11px; letter-spacing: .18em; text-transform: uppercase; color: var(--dim); margin-left: 12px; }
.series .blurb { color: var(--dim); font-size: 16.5px; margin: 4px 0 8px; max-width: 62ch; }
.series .facts { display: grid; grid-template-columns: repeat(3, minmax(0, 1fr)); gap: 6px 18px; font-family: var(--mono); font-size: 12px; color: var(--ink); margin: 0 0 12px; line-height: 1.5; }
.series .facts span { display: block; font-size: 10px; letter-spacing: .14em; text-transform: uppercase; color: var(--faint); margin-bottom: 2px; }
.series .play { font-family: var(--mono); font-size: 11px; letter-spacing: .16em; text-transform: uppercase; color: var(--amber); border-bottom: 1px solid rgba(240,180,106,.5); }
.series .play:hover { color: var(--warm); border-color: var(--warm); }
.backlog { list-style: none; padding: 0; margin: 0; display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 0 40px; border-top: 1px solid var(--line); }
.backlog li { display: grid; grid-template-columns: 36px minmax(0, 1fr); gap: 12px; padding: 12px 0; border-bottom: 1px solid var(--line); font-size: 15.5px; color: var(--dim); }
.backlog .num { font-family: var(--mono); font-size: 11px; color: var(--faint); padding-top: 4px; letter-spacing: .1em; }
.backlog b { font-family: var(--display); font-weight: 400; color: var(--ink); font-size: 17px; letter-spacing: .03em; margin-right: 8px; }
@media (max-width: 720px) { .series li { grid-template-columns: 1fr; } .series .icon { display: none; } .series .num { padding-top: 0; } .series .facts { grid-template-columns: 1fr; } .backlog { grid-template-columns: 1fr; } }

/* hub: the s-plane primer */
.primer { display: grid; grid-template-columns: minmax(0, 1fr) 380px; gap: 28px 44px; align-items: start; }
.primer svg { width: 100%; height: auto; display: block; border: 1px solid var(--line); background: var(--bg2); }
.primer svg text { font-family: var(--mono); }
@media (max-width: 860px) { .primer { grid-template-columns: 1fr; } }
.four { display: grid; grid-template-columns: repeat(2, 1fr); gap: 24px 40px; margin: 8px 0 8px; max-width: 760px; }
.four h3 { margin: 0 0 6px; }
.four p { font-size: 16px; color: var(--dim); margin: 0; }
@media (max-width: 640px) { .four { grid-template-columns: 1fr; } }

footer { padding: 36px 0 64px; font-family: var(--mono); font-size: 11px; color: var(--faint); letter-spacing: .06em; border-top: 1px solid var(--line); line-height: 1.9; }
footer a { color: var(--dim); border: 0; }
footer a:hover { color: var(--warm); }
:focus-visible { outline: 1px solid var(--blue); outline-offset: 3px; }
@media (prefers-reduced-motion: reduce) { a, .btn { transition: none; } }