/* Charlie: black page, warm paper-white ink, one ribbon-red accent.
   Courier Prime for reading and typing; Special Elite for display type. */
:root {
  --bg: #000;
  --surface: #000;
  --ink: #ece6d6;          /* paper white */
  --ink-2: #b3ad9f;
  --muted: #736e63;
  --faint: #3a3731;
  --line: #24221e;
  --accent: #e0442e;       /* typewriter ribbon red */
  --miss: #f59a3c;         /* amber: the key you pressed by mistake */
  --accent-ink: #000;
  --good: #ece6d6;
  --bad: #e0442e;
  --current: transparent;
  --key: #0c0b0a;
  --heat-0: #1f1310;
  --heat-1: #e0442e;
  --mono: 'Courier Prime', 'Courier New', Courier, monospace;
  --display: 'Special Elite', 'Courier Prime', Courier, monospace;
  color-scheme: dark;
}

* { box-sizing: border-box; }
html { background: var(--bg); }
body {
  margin: 0; background: var(--bg); color: var(--ink);
  font: 17px/1.6 var(--mono);
  -webkit-font-smoothing: antialiased;
}
::selection { background: var(--accent); color: var(--bg); }
a { color: var(--ink); text-decoration: none; }
h1 { font: 400 2rem/1.2 var(--display); margin: 0 0 .75rem; letter-spacing: .01em; }
h2 { font: 400 1.25rem/1.3 var(--display); margin: 2.5rem 0 .75rem; }
h3 { font-size: .75rem; font-weight: 400; margin: 0 0 1rem; text-transform: uppercase; letter-spacing: .18em; color: var(--muted); }
p { margin: 0 0 1rem; }
.muted { color: var(--muted); }
.small { font-size: .85rem; }
.error { color: var(--bad); min-height: 1.4em; }
kbd {
  font: inherit; font-size: .9em; color: var(--ink);
  border: 1px solid var(--faint); border-radius: 3px; padding: 0 .35em; margin: 0 .15em;
}
code { font-family: var(--mono); }

/* Header */
.top {
  display: flex; align-items: baseline; gap: 2.5rem; flex-wrap: wrap;
  max-width: 960px; margin: 0 auto; padding: 2rem 16px 1rem;
}
.brand { font: 400 1.35rem var(--display); color: var(--ink); }
#nav { display: flex; gap: 1.6rem; flex-wrap: wrap; }
#nav a {
  color: var(--muted); font-size: .8rem; text-transform: uppercase; letter-spacing: .16em;
  padding: .2rem 0; transition: color .15s;
}
#nav a:hover { color: var(--ink); }
#nav a.active { color: var(--ink); }
#nav a.active::before { content: '·'; color: var(--accent); margin-right: .35em; }
.badge {
  display: inline-block; margin-left: .4rem; color: var(--accent);
  font-size: .75rem; letter-spacing: .08em; vertical-align: 1px;
}
.badge::before { content: '('; } .badge::after { content: ')'; }
main { max-width: 960px; margin: 0 auto; padding: 2rem 16px 6rem; }

/* Controls */
button, .button {
  font: inherit; font-size: .8rem; text-transform: uppercase; letter-spacing: .16em; cursor: pointer;
  display: inline-block; padding: .7rem 1.4rem; border-radius: 0;
  border: 1px solid var(--faint); background: transparent; color: var(--ink);
  transition: border-color .15s, background .15s, color .15s;
}
button:hover, .button:hover { border-color: var(--ink); }
.primary { background: var(--ink); color: var(--bg); border-color: var(--ink); }
.primary:hover { background: transparent; color: var(--ink); }
button.link { border: 0; padding: .3rem .5rem; color: var(--muted); letter-spacing: .1em; }
button.link:hover { color: var(--ink); }
input, select, textarea {
  font: inherit; width: 100%; padding: .6rem 0; border-radius: 0;
  border: 0; border-bottom: 1px solid var(--faint); background: transparent; color: var(--ink);
}
input:focus, select:focus { outline: none; border-bottom-color: var(--ink); }
select option { background: var(--bg); }
label { display: block; font-size: .75rem; color: var(--muted); margin-bottom: 1.5rem; text-transform: uppercase; letter-spacing: .16em; }
label input, label select { margin-top: .3rem; font-size: 1rem; text-transform: none; letter-spacing: 0; }
label.toggle { display: flex; gap: .75rem; align-items: center; text-transform: none; letter-spacing: 0; font-size: .9rem; }
label.toggle input { width: auto; margin: 0; accent-color: var(--accent); }

/* Structure: rules and whitespace, no boxes */
.card { border-top: 1px solid var(--line); padding: 1.75rem 0; margin: 0; }
.card h2 { margin-top: 0; }
.narrow { max-width: 440px; }
.row { display: flex; align-items: baseline; justify-content: space-between; gap: 1rem; flex-wrap: wrap; }
.row.gap { justify-content: flex-start; gap: 1rem; margin-top: 2rem; }
.grid2 { display: grid; grid-template-columns: repeat(auto-fit, minmax(240px, 1fr)); column-gap: 3rem; }
.cards { list-style: none; padding: 0; margin: 0; }
.list { margin: 0; padding: 0; list-style: none; }
.list li { padding: .3rem 0; }
.list a { border-bottom: 1px solid var(--faint); }
.list a:hover { border-color: var(--ink); }
ol.compact { margin: 0; padding-left: 1.6rem; color: var(--muted); }
ol.compact li { padding: .15rem 0; }
ol.compact li > * , ol.compact li { color: var(--ink); }
ol.compact li::marker { color: var(--muted); }

.hero { padding: 4rem 0 3.5rem; }
.hero h1 { font-size: clamp(2.2rem, 6vw, 3.6rem); max-width: 18ch; margin-bottom: 2.5rem; line-height: 1.1; }
.eyebrow { text-transform: uppercase; letter-spacing: .2em; font-size: .72rem; color: var(--muted); margin: 0 0 1rem; }
.coach-callout h2 { color: var(--ink); }
.coach-callout h2::before { content: '✱ '; color: var(--accent); }

.tiles { display: grid; grid-template-columns: repeat(auto-fit, minmax(140px, 1fr)); gap: 0; margin: 1.5rem 0 2.5rem; border-top: 1px solid var(--line); }
.tile { padding: 1.5rem 0 0; }
.tile-value { font: 400 2.4rem/1 var(--display); font-variant-numeric: tabular-nums; }
.tile-label { color: var(--muted); font-size: .7rem; text-transform: uppercase; letter-spacing: .18em; margin-top: .6rem; }

/* Learn */
.stages { margin-top: 2.5rem; border-top: 1px solid var(--line); }
.stage { display: grid; grid-template-columns: minmax(200px, 260px) 1fr; gap: 1.5rem; align-items: baseline; padding: .9rem 0; border-bottom: 1px solid var(--line); }
.stage-title { display: flex; gap: .75rem; align-items: baseline; }
.keycaps kbd { margin: 0 .1rem 0 0; }
.stage-lessons { display: flex; gap: 1.75rem; flex-wrap: wrap; }
.pill { color: var(--muted); font-size: .9rem; transition: color .15s; }
.pill:hover { color: var(--ink); }
.pill.done { color: var(--ink); }
.pill .tick { color: var(--accent); }
@media (max-width: 640px) { .stage { grid-template-columns: 1fr; gap: .4rem; } }
.form { max-width: 560px; }

/* Typing */
.lesson { max-width: 860px; margin: 0 auto; }
.lesson-head { display: flex; justify-content: space-between; align-items: flex-end; gap: 1rem; flex-wrap: wrap; margin: 1.5rem 0 3rem; }
.lesson-head h1 { margin: 0; font-size: 1.6rem; }
/* Five lines tall; the current line stays in the middle and the text rolls
   past it. Two lines of padding let the first and last lines reach the centre. */
.typing-text {
  font: 400 1.75rem/2.2 var(--mono); height: calc(2.2em * 5); padding: calc(2.2em * 2) 0;
  overflow: hidden; outline: none; color: #5e594f; position: relative;
  scroll-behavior: smooth;
  -webkit-mask-image: linear-gradient(to bottom, transparent 0, #000 26%, #000 74%, transparent 100%);
  mask-image: linear-gradient(to bottom, transparent 0, #000 26%, #000 74%, transparent 100%);
}
@media (prefers-reduced-motion: reduce) { .typing-text { scroll-behavior: auto; } }
.typing-text .word { white-space: nowrap; }
.typing-text .ch { position: relative; transition: color .06s; }
.typing-text .ch.done { color: var(--ink); }
.typing-text .ch.done.had-err { color: var(--accent); }
.typing-text .ch.current { color: var(--ink); }
.typing-text .ch.wrong::after { background: var(--miss) !important; animation: none !important; }
.typing-text .ch.wrong::before {
  content: attr(data-wrong); position: absolute; left: 50%; top: -.55em; transform: translateX(-50%);
  font-size: .55em; line-height: 1; color: var(--miss); pointer-events: none;
}
.typing-text .ch.current::after {
  content: ''; position: absolute; left: 0; right: 0; bottom: .28em; height: 2px;
  background: var(--accent); animation: blink 1.1s steps(1) infinite;
}
.typing-text .ch.nl { font-size: .7em; color: var(--line); }
.typing-text .ch.nl.done { color: var(--faint); }
.typing-text .ch.flash { animation: strike .22s ease-out; }
@keyframes blink { 50% { opacity: 0; } }
@keyframes strike { 0% { color: var(--accent); transform: translateY(-2px); } 100% { transform: none; } }
.key-intro { margin: -1.5rem 0 0; max-width: 640px; }
.key-intro ul { list-style: none; margin: 0; padding: 0; border-top: 1px solid var(--line); }
.key-intro li { display: flex; gap: 1rem; align-items: baseline; padding: .6rem 0; border-bottom: 1px solid var(--line); }
.key-intro kbd { min-width: 1.8em; text-align: center; font-size: 1.1rem; }
.finger-hint { margin: 0; color: var(--ink-2); font-size: .95rem; min-height: 1.6em; }
.finger-hint kbd { margin: 0 .5rem 0 0; }
.finger-hint + .live { margin-top: .5rem; }
.live { margin: 2.5rem 0; color: var(--muted); font-size: .8rem; letter-spacing: .12em; text-transform: uppercase; font-variant-numeric: tabular-nums; min-height: 1.5em; }

.results { max-width: 680px; margin: 3rem auto; }
.results .tiles { margin-top: 1rem; }
.verdict { font-family: var(--display); font-size: 1.2rem; }
.verdict.good { color: var(--ink); }
.verdict.good::before { content: '✓ '; color: var(--accent); }
.results .row.gap + p { margin-top: 1.25rem; }
.feedback { display: flex; gap: .5rem; align-items: center; margin-top: 2rem; }

/* Keyboard: outlines only */
.kb { display: flex; flex-direction: column; gap: 6px; max-width: 700px; margin: 2rem auto 0; user-select: none; }
.kb-row { display: flex; gap: 6px; }
.kb-key {
  flex: 1 1 0; min-width: 0; height: 40px; border-radius: 4px; background: transparent;
  border: 1px solid var(--line); display: flex; align-items: center; justify-content: center;
  font: .75rem var(--mono); color: var(--muted); position: relative; transition: background .08s, color .08s, border-color .08s;
}
.kb-key.wide { flex-grow: 1.5; } .kb-key.wider { flex-grow: 1.85; } .kb-key.widest { flex-grow: 2.35; }
.kb-key.space { flex-grow: 6; margin: 0 22%; }
/* Finger guide: a small dot, shade by finger (index brightest) */
.kb:not(.heat) .kb-key[data-finger]::after {
  content: ''; position: absolute; bottom: 5px; width: 3px; height: 3px; border-radius: 50%;
}
.kb-key[data-finger="0"]::after, .kb-key[data-finger="7"]::after { background: #4a463e; }
.kb-key[data-finger="1"]::after, .kb-key[data-finger="6"]::after { background: #6f6a5f; }
.kb-key[data-finger="2"]::after, .kb-key[data-finger="5"]::after { background: #9a9486; }
.kb-key[data-finger="3"]::after, .kb-key[data-finger="4"]::after { background: #ece6d6; }
.kb-key.next { background: var(--ink); color: var(--bg); border-color: var(--ink); }
.kb-key.miss { border-color: var(--miss); color: var(--miss); animation: miss .7s ease-out forwards; }
@keyframes miss { 0% { background: var(--miss); color: #000; } 100% { background: transparent; } }
.kb-key.next::after { background: var(--bg) !important; }
.kb.heat .kb-key.has-heat {
  background: color-mix(in oklab, var(--heat-0), var(--heat-1) calc(var(--heat) * 100%));
  border-color: transparent; color: var(--ink-2); cursor: default;
}
.kb.heat .kb-key.hot { color: #000; }
@media (max-width: 640px) {
  .kb-key { height: 30px; font-size: .62rem; }
  .typing-text { font-size: 1.3rem; }
  .top { gap: 1rem; padding-top: 1.25rem; }
}

.seg { display: inline-flex; gap: 1.25rem; }
.seg button { border: 0; padding: .2rem 0; color: var(--muted); font-size: .72rem; }
.seg button.active { color: var(--ink); border-bottom: 1px solid var(--accent); }

/* Chart */
.chart { position: relative; }
.chart svg { width: 100%; height: auto; display: block; }
.chart .grid { stroke: var(--line); stroke-width: 1; }
.chart .axis { fill: var(--muted); font-size: 11px; font-family: var(--mono); }
.chart .line { fill: none; stroke: var(--ink); stroke-width: 2; stroke-linejoin: round; stroke-linecap: round; }
.chart .cross { stroke: var(--faint); stroke-width: 1; stroke-dasharray: 2 4; }
.chart .dot { fill: var(--accent); stroke: var(--bg); stroke-width: 2; }
.chart .tip {
  position: absolute; pointer-events: none; background: var(--bg); border: 1px solid var(--faint);
  padding: .5rem .7rem; font-size: .78rem; white-space: nowrap;
}

/* Games share a stage */
.game { max-width: 860px; margin: 0 auto; }
.game-stage { position: relative; height: 420px; border-top: 1px solid var(--line); border-bottom: 1px solid var(--line); overflow: hidden; }
.game-stage + p { margin-top: 1rem; }
.game-hud { display: flex; justify-content: space-between; color: var(--muted); font-size: .8rem; letter-spacing: .12em; text-transform: uppercase; margin: 1rem 0; font-variant-numeric: tabular-nums; }