/* ============================================================================
 * mmux.org — v3 stylesheet
 *
 * Flat, sharp, terminal-honest. No glows, no gradients, minimal radius. The
 * palette is tmux's: a green accent (the status-bar green) over neutral
 * terminal greys; ANSI-ish semantic colors live only inside the window. The
 * centerpiece is the scroll-through demo — a sticky terminal that scrubs scenes.
 *
 * Map: tokens → reset → primitives → nav → hero → demo (sticky scrub) →
 *      #tw window → syntax tones → features → how → install → footer →
 *      responsive → reduced-motion/focus → polish.
 * ========================================================================== */

/* ============================================================================
 * design tokens
 * ========================================================================== */
:root {
  /* base surfaces — neutral terminal dark, flat */
  --bg:        #0d0e10;
  --bg-2:      #131416;
  --surface:   #17181b;
  --surface-2: #1d1f22;
  --surface-3: #26282c;
  --border:    #2a2d31;
  --border-2:  #3a3e44;

  /* ink */
  --text:   #d7d9dc;
  --text-2: #abafb5;
  --muted:  #7c8087;
  --faint:  #4f535a;

  /* accent — tmux green. used sparingly: status bar, active row, links, cursor */
  --green:        #6e9e72;   /* muted sage — subtle, not neon */
  --green-bright: #8bbf8f;   /* legible muted-green text on dark */
  --green-dim:    #4f7355;
  --accent:       #6e9e72;
  --accent-soft:  rgba(110, 158, 114, .13);

  /* terminal ANSI-ish semantic (de-neoned, classic) — inside the window only */
  --red:     #cf8080;
  --yellow:  #c6a96c;
  --blue:    #7ea7c9;
  --magenta: #a98cc4;
  --cyan:    #6fa8ad;

  --running:   var(--green);
  --attention: var(--red);
  --warn:      var(--yellow);
  --info:      var(--blue);
  --add:       var(--green);
  --del:       var(--red);
  --ai:        var(--magenta);

  /* syntax token tones (terminal content) */
  --tok-kw:      #a98cc4;
  --tok-fn:      #7ea7c9;
  --tok-str:     #8aa978;
  --tok-num:     #c6a96c;
  --tok-comment: #7c8490;
  --tok-type:    #7ea7c9;
  --tok-path:    #88b0cf;
  --tok-op:      #abafb5;

  /* depth — one subtle shadow, no glows */
  --shadow: 0 12px 38px -22px rgba(0, 0, 0, .9);
  --ring:   0 0 0 2px var(--bg), 0 0 0 4px var(--green);

  /* shape — sharp */
  --radius:    4px;
  --radius-sm: 3px;

  /* type — system mono stack only, no remote fonts */
  --font: ui-monospace, "SF Mono", "JetBrains Mono", "Cascadia Code", "Fira Code", Menlo, Consolas, monospace;

  /* scale */
  --page-max: 1120px;
  --measure: 60ch;
}

/* ============================================================================
 * reset & base
 * ========================================================================== */
*,
*::before,
*::after { box-sizing: border-box; }

html {
  scroll-behavior: smooth;
  -webkit-text-size-adjust: 100%;
}

body {
  margin: 0;
  font-family: var(--font);
  font-size: 16px;
  line-height: 1.6;
  color: var(--text-2);
  background: var(--bg);
  overflow-x: hidden;
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
}

a {
  color: var(--text);
  text-decoration: none;
  transition: color .15s ease;
}
a:hover { color: var(--green-bright); }

button { font-family: inherit; }
ul { margin: 0; padding: 0; list-style: none; }

[aria-hidden="true"] { user-select: none; }

.skip-link {
  position: fixed;
  top: -100%;
  left: 1rem;
  z-index: 100;
  padding: .6rem 1rem;
  background: var(--surface-2);
  color: var(--text);
  border: 1px solid var(--green);
  border-radius: var(--radius-sm);
}
.skip-link:focus { top: 1rem; }

section {
  position: relative;
  max-width: var(--page-max);
  margin: 0 auto;
  padding: 6rem 1.5rem;
}

/* ============================================================================
 * primitives — kicker, accent text, headings, buttons, copy
 * ========================================================================== */

/* lowercase mono eyebrow above each section (e.g. "// what you get") */
.kicker,
.hero-kicker,
.caption-kicker {
  font-size: .82rem;
  font-weight: 500;
  letter-spacing: .02em;
  color: var(--green);
  margin: 0 0 1rem;
}

/* accent text fragment — a solid green word inside a heading */
.grad {
  color: var(--green-bright);
}
.brand,
.hero-wordmark,
.footer-brand {
  color: var(--text);
}

.section-h2 {
  font-size: clamp(1.6rem, 3.6vw, 2.3rem);
  font-weight: 700;
  letter-spacing: -.015em;
  line-height: 1.15;
  color: var(--text);
  margin: 0 0 2.5rem;
}

/* buttons — flat, no glow ------------------------------------------------ */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: .5rem;
  padding: .6rem 1.2rem;
  font-size: .92rem;
  font-weight: 600;
  border-radius: var(--radius-sm);
  border: 1px solid transparent;
  cursor: pointer;
  transition: background .15s ease, border-color .15s ease, color .15s ease;
}
.btn-brand {
  color: #08130a;
  background: var(--green);
  border-color: var(--green);
}
.btn-brand:hover {
  color: #08130a;
  background: var(--green-bright);
  border-color: var(--green-bright);
}
.btn-ghost {
  color: var(--text);
  background: transparent;
  border-color: var(--border-2);
}
.btn-ghost:hover {
  color: var(--text);
  border-color: var(--muted);
  background: var(--surface);
}

/* inline copy chip in install rows */
.copy {
  flex: none;
  padding: .32rem .65rem;
  font-size: .8rem;
  font-weight: 600;
  color: var(--text-2);
  background: var(--surface-3);
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  cursor: pointer;
  transition: color .15s ease, border-color .15s ease, background .15s ease;
}
.copy:hover {
  color: var(--text);
  border-color: var(--border-2);
  background: var(--surface-2);
}
.copy--copied {
  color: var(--green-bright);
  border-color: var(--green-dim);
  background: var(--accent-soft);
}

/* ============================================================================
 * nav — slim, sticky, opaque (no blur theatrics)
 * ========================================================================== */
.site-nav {
  position: sticky;
  top: 0;
  z-index: 50;
  background: rgba(13, 14, 16, .85);
  backdrop-filter: blur(8px);
  -webkit-backdrop-filter: blur(8px);
  border-bottom: 1px solid var(--border);
}
.nav-inner {
  max-width: var(--page-max);
  margin: 0 auto;
  padding: .85rem 1.5rem;
  display: flex;
  align-items: center;
  gap: 1.5rem;
}
.brand {
  font-size: 1.25rem;
  font-weight: 700;
  letter-spacing: -.02em;
}
.brand::before { content: "$ "; color: var(--green); font-weight: 500; }
.nav-links {
  display: flex;
  align-items: center;
  gap: .85rem;
  margin-left: auto;
  font-size: .9rem;
  color: var(--muted);
}
.nav-links a { color: var(--text-2); }
.nav-links a:hover { color: var(--green-bright); }
.nav-sep { color: var(--faint); }

/* ============================================================================
 * hero — compact, so the demo is reached fast
 * ========================================================================== */
#hero {
  text-align: center;
  padding-top: 5rem;
  padding-bottom: 2.5rem;
}
.hero-wordmark {
  font-size: clamp(2.6rem, 7vw, 4.4rem);
  font-weight: 700;
  letter-spacing: -.03em;
  line-height: 1;
  margin: 0 0 1.3rem;
}
.hero-caret {
  color: var(--green);
  margin-left: .04em;
  animation: caret-blink 1.1s steps(1) infinite;
}
@keyframes caret-blink { 50% { opacity: 0; } }

.hero-tagline {
  font-size: clamp(1.15rem, 2.4vw, 1.5rem);
  font-weight: 600;
  color: var(--text);
  margin: 0 auto .85rem;
  max-width: 34ch;
}
.hero-sub {
  font-size: 1rem;
  line-height: 1.7;
  color: var(--text-2);
  max-width: 56ch;
  margin: 0 auto 2.2rem;
}

/* the single install row — flat bordered box, no glow */
.hero-install {
  display: inline-flex;
  align-items: center;
  gap: .7rem;
  padding: .6rem .6rem .6rem 1rem;
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  max-width: 100%;
}
.hero-install-prompt { color: var(--green); font-weight: 700; }
.hero-install-cmd {
  font-size: .96rem;
  color: var(--text);
  white-space: nowrap;
  overflow-x: auto;
}

.hero-meta {
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
  gap: .5rem;
  margin: 1.5rem auto 0;
}
.hero-chip {
  font-size: .8rem;
  color: var(--text-2);
  padding: .3rem .7rem;
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
}

.scroll-cue {
  margin: 2.5rem 0 0;
  font-size: .82rem;
  color: var(--muted);
  animation: cue-bob 2s ease-in-out infinite;
}
@keyframes cue-bob {
  0%, 100% { transform: translateY(0); opacity: .7; }
  50%      { transform: translateY(4px); opacity: 1; }
}

/* ============================================================================
 * the demo — THE centerpiece. A TALL track so the sticky stage scrubs scenes.
 * #demo height drives how much scroll each scene gets (~80vh/scene over 9).
 * The driver (tui.js) maps demo scroll-progress → scene index.
 * ========================================================================== */
#demo {
  /* CRITICAL: the track must be much taller than the 100vh sticky stage,
   * otherwise progress is always 0 and the walkthrough never scrubs. */
  min-height: 760vh;
  padding: 0 1.5rem;
  max-width: var(--page-max);
  margin: 0 auto;
}
.demo-stage {
  position: sticky;
  top: 0;
  min-height: 100vh;
  display: flex;
  align-items: center;
  padding: 4.5rem 0;
}
.demo-grid {
  display: grid;
  grid-template-columns: minmax(0, 1.6fr) minmax(0, 1fr);
  gap: 2.75rem;
  align-items: center;
  width: 100%;
}

/* caption column — children absolutely stacked, cross-faded by --visible */
.demo-caption {
  position: relative;
  min-height: 13rem;
}
.caption {
  position: absolute;
  inset: 0;
  display: flex;
  flex-direction: column;
  justify-content: center;
  opacity: 0;
  transform: translateY(12px);
  transition: opacity .45s ease, transform .45s ease;
  pointer-events: none;
}
.caption--visible {
  opacity: 1;
  transform: translateY(0);
  pointer-events: auto;
}
.caption-title {
  font-size: clamp(1.4rem, 3vw, 2.1rem);
  font-weight: 700;
  letter-spacing: -.02em;
  line-height: 1.18;
  color: var(--text);
  margin-bottom: .8rem;
}
.caption-body {
  font-size: 1rem;
  line-height: 1.7;
  color: var(--text-2);
  max-width: var(--measure);
}

/* reduced-motion path: captions become a static stacked list */
.demo-caption--static { min-height: 0; }
.demo-caption--static .caption {
  position: static;
  inset: auto;
  opacity: 1;
  transform: none;
  display: block;
  margin-bottom: 2.25rem;
  pointer-events: auto;
}

/* ============================================================================
 * the terminal window (#tw) — flat, crisp, with a tmux-green status bar
 * ========================================================================== */
.tw {
  position: relative;
  display: flex;
  flex-direction: column;
  min-width: 0;
  background: var(--surface);
  border: 1px solid var(--border-2);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
  overflow: hidden;
  font-size: .82rem;
  line-height: 1.6;
  transition: border-color .2s ease;
  height: 32rem;
}
/* engaged sandbox: a crisp green edge, not a glow */
.tw.tw--engaged { border-color: var(--green); }

/* titlebar — minimal, de-mac'd (monochrome dots) ------------------------- */
.tw-bar {
  flex: none;
  display: flex;
  align-items: center;
  gap: .65rem;
  padding: .5rem .85rem;
  background: var(--surface-2);
  border-bottom: 1px solid var(--border);
}
.tw-lights { display: inline-flex; gap: .4rem; }
.tw-lights i {
  width: .62rem;
  height: .62rem;
  border-radius: 50%;
  background: var(--faint);
}
.tw-titlebar-name {
  font-weight: 600;
  color: var(--text);
  margin-left: .3rem;
}
.tw-titlebar-path { color: var(--muted); }
.tw-titlebar-meta {
  margin-left: auto;
  color: var(--green);
  font-size: .76rem;
}

/* body: sidebar | main | panel ------------------------------------------ */
.tw-body {
  flex: 1;
  display: flex;
  min-height: 0;
}

/* sidebar */
.tw-sidebar {
  flex: none;
  width: 188px;
  background: var(--bg-2);
  border-right: 1px solid var(--border);
  padding: .55rem 0;
  overflow-y: auto;
}
.sb-project {
  padding: .35rem .85rem;
  font-size: .76rem;
  font-weight: 700;
  letter-spacing: .03em;
  color: var(--muted);
}
.sb-project--active { color: var(--text); }
.sb-project--active::before { content: "▸ "; color: var(--green); }

.sb-section { margin-bottom: .5rem; }
.sb-head {
  padding: .45rem .85rem .3rem;
  font-size: .67rem;
  font-weight: 600;
  letter-spacing: .14em;
  text-transform: uppercase;
  color: var(--muted);
}

.sb-row {
  position: relative;
  display: flex;
  align-items: center;
  gap: .5rem;
  padding: .38rem .85rem;
  color: var(--text-2);
  white-space: nowrap;
  overflow: hidden;
}
/* active row = green-soft fill + a solid green left edge + brighter ink */
.sb-row--active {
  background: var(--accent-soft);
  color: var(--text);
}
.sb-row--active::before {
  content: "";
  position: absolute;
  left: 0;
  top: 0;
  bottom: 0;
  width: 2px;
  background: var(--green);
}

/* status dot, colored by data-status — solid, no glow */
.sb-dot {
  flex: none;
  width: .5rem;
  height: .5rem;
  border-radius: 50%;
  background: var(--muted);
}
.sb-dot[data-status="running"] { background: var(--green); }
.sb-dot[data-status="exited"]  { background: var(--faint); }
.sb-dot[data-status="stopped"] { background: var(--muted); }

.sb-name { flex: none; font-weight: 500; }
.sb-sub {
  flex: 1;
  min-width: 0;
  color: var(--muted);
  font-size: .76rem;
  overflow: hidden;
  text-overflow: ellipsis;
  white-space: nowrap;
}
/* coral attention bell; JS toggles [hidden] */
.sb-bell {
  flex: none;
  margin-left: auto;
  color: var(--attention);
  font-size: .7rem;
  animation: bell-pulse 1s ease-in-out infinite;
}
.sb-bell[hidden] { display: none; }
@keyframes bell-pulse {
  0%, 100% { opacity: 1; }
  50%      { opacity: .45; }
}

/* launcher rows: a muted "+ New …" that greens on hover */
.sb-row--launcher { color: var(--muted); }
.sb-row--launcher .sb-name { font-weight: 400; }
.sb-plus {
  flex: none;
  width: .5rem;
  text-align: center;
  color: var(--muted);
  font-weight: 700;
}
.sb-row--launcher:hover { color: var(--green-bright); }
.sb-row--launcher:hover .sb-plus { color: var(--green-bright); }
.sb-row--launcher.sb-row--active { color: var(--text); }

/* main pane */
.tw-main {
  flex: 1;
  display: flex;
  flex-direction: column;
  min-width: 0;
  background: var(--surface);
}
.tw-tab {
  flex: none;
  padding: .42rem .9rem;
  font-size: .73rem;
  font-weight: 600;
  letter-spacing: .03em;
  color: var(--text-2);
  background: var(--bg-2);
  border-bottom: 1px solid var(--border);
}
.tw-tab[hidden] { display: none; }

.tw-screen {
  flex: 1;
  padding: .8rem 1rem;
  overflow: auto;
  line-height: 1.65;
  color: var(--text-2);
}
.screen-line {
  white-space: pre-wrap;
  word-break: break-word;
}
.screen-placeholder {
  color: var(--muted);
  white-space: pre-line;
  padding: 1.4rem .5rem;
}
/* green block cursor on the last line */
.screen-cursor {
  display: inline-block;
  color: var(--green);
  animation: caret-blink 1.1s steps(1) infinite;
}

/* line-level tints: a faint colored wash + a colored gutter bar */
.ln-add {
  background: rgba(110, 158, 114, .1);
  color: var(--add);
  box-shadow: inset 2px 0 0 var(--green);
}
.ln-del {
  background: rgba(207, 128, 128, .1);
  color: var(--del);
  box-shadow: inset 2px 0 0 var(--red);
}
.ln-cmd { color: var(--text); }
.ln-dim { color: var(--muted); }

/* the active pane gets brighter ink */
.tw--main-focus .tw-tab { color: var(--text); border-bottom-color: var(--border-2); }
.tw--main-focus .tw-screen { color: var(--text); }

/* panel (native git) */
.tw-panel {
  flex: none;
  width: 208px;
  display: flex;
  flex-direction: column;
  background: var(--bg-2);
  border-left: 1px solid var(--border);
}
.tw-panel[hidden] { display: none; }
.tw-panel-head {
  flex: none;
  padding: .42rem .8rem;
  font-size: .72rem;
  font-weight: 600;
  color: var(--text-2);
  background: var(--surface-2);
  border-bottom: 1px solid var(--border);
}
.tw-panel-screen {
  flex: 1;
  padding: .55rem .5rem;
  overflow: auto;
  font-size: .76rem;
  line-height: 1.7;
  color: var(--text-2);
}
.tw--panel-focus .tw-panel-head { color: var(--text); border-bottom-color: var(--border-2); }

/* status bar — the tmux-green signature: green bar, dark text */
.tw-status {
  flex: none;
  padding: .35rem .85rem;
  font-size: .73rem;
  font-weight: 500;
  color: #08130a;
  background: var(--green);
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}

/* toast (scene 6) — flat notification card */
.tw-toast {
  position: absolute;
  top: 3rem;
  right: 1rem;
  z-index: 6;
  max-width: 16rem;
  padding: .65rem .8rem;
  background: var(--surface-2);
  border: 1px solid var(--border-2);
  border-left: 2px solid var(--red);
  border-radius: var(--radius-sm);
  box-shadow: var(--shadow);
  animation: toast-in .3s ease;
}
.tw-toast[hidden] { display: none; }
@keyframes toast-in {
  from { opacity: 0; transform: translateY(-6px); }
  to   { opacity: 1; transform: none; }
}
.toast-head {
  display: flex;
  align-items: center;
  gap: .4rem;
  margin-bottom: .2rem;
}
.toast-dot { color: var(--red); font-size: .6rem; }
.toast-app { font-weight: 600; color: var(--text); }
.toast-title { color: var(--text-2); font-size: .78rem; }
.toast-body { color: var(--muted); font-size: .78rem; line-height: 1.5; }

/* overlay (scene 4) — ssh disconnect / reattach scrim */
.tw-overlay {
  position: absolute;
  inset: 0;
  z-index: 5;
  display: flex;
  align-items: center;
  justify-content: center;
  text-align: center;
  padding: 1.5rem;
  font-size: .92rem;
  color: var(--text);
  background: rgba(13, 14, 16, .82);
}
.tw-overlay[hidden] { display: none; }
.tw-overlay[data-overlay="disconnected"] { color: var(--warn); }
.tw-overlay[data-overlay="reattached"]   { color: var(--green); }

/* sandbox hint (finale) — flat pill-less chip */
.tw-sandbox-hint {
  position: absolute;
  bottom: 2.4rem;
  left: 50%;
  transform: translateX(-50%);
  z-index: 6;
  padding: .38rem .85rem;
  font-size: .77rem;
  color: var(--text);
  background: var(--surface-2);
  border: 1px solid var(--green);
  border-radius: var(--radius-sm);
  animation: hint-bob 2s ease-in-out infinite;
}
.tw-sandbox-hint[hidden] { display: none; }
@keyframes hint-bob {
  0%, 100% { transform: translate(-50%, 0); }
  50%      { transform: translate(-50%, -3px); }
}

/* ============================================================================
 * syntax token tones — every .tok-<tone> renderLine() can emit
 * ========================================================================== */
.tok-kw      { color: var(--tok-kw); }
.tok-fn      { color: var(--tok-fn); }
.tok-str     { color: var(--tok-str); }
.tok-num     { color: var(--tok-num); }
.tok-comment { color: var(--tok-comment); }
.tok-type    { color: var(--tok-type); }
.tok-path    { color: var(--tok-path); }
.tok-op      { color: var(--tok-op); }
.tok-add     { color: var(--add); }
.tok-del     { color: var(--del); }
.tok-ok      { color: var(--green); }
.tok-warn    { color: var(--warn); }
.tok-info    { color: var(--info); }
.tok-ai      { color: var(--ai); font-weight: 600; }
.tok-dim     { color: var(--muted); }
.tok-prompt,
.tok-brand   { color: var(--green-bright); font-weight: 700; }

/* ============================================================================
 * features — flat list-cards, green-stroke icons, no glow/lift
 * ========================================================================== */
.feature-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 1rem;
}
.feature {
  padding: 1.4rem;
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  transition: border-color .15s ease;
}
.feature:hover { border-color: var(--border-2); }
.feature-icon {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 2.3rem;
  height: 2.3rem;
  margin-bottom: 1rem;
  color: var(--green);
  background: var(--accent-soft);
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
}
.feature-icon svg { width: 1.2rem; height: 1.2rem; }
.feature-title {
  font-size: 1.02rem;
  font-weight: 600;
  color: var(--text);
  margin: 0 0 .5rem;
}
.feature-desc {
  font-size: .9rem;
  line-height: 1.65;
  color: var(--text-2);
  margin: 0;
}

/* ============================================================================
 * how it works — flat diagram (real nodes + a thin green connector)
 * ========================================================================== */
.how-diagram {
  display: flex;
  flex-direction: column;
  align-items: center;
  margin-bottom: 2.5rem;
}
.how-node {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: .2rem;
  padding: .8rem 1.4rem;
  background: var(--surface);
  border: 1px solid var(--border-2);
  border-radius: var(--radius);
}
.how-node-title { font-weight: 600; color: var(--text); }
.how-node-sub { font-size: .8rem; color: var(--muted); }

.how-connector { width: 36px; height: 56px; }
.how-connector-path { stroke-dasharray: 4 5; }

/* the tmux "jail" — a dashed (not glowing) container */
.how-jail {
  width: 100%;
  max-width: 620px;
  padding: 1.4rem;
  background: var(--bg-2);
  border: 1px dashed var(--border-2);
  border-radius: var(--radius);
}
.how-jail-head {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: .6rem;
  margin-bottom: 1rem;
}
.how-jail-chip {
  font-size: .8rem;
  font-weight: 600;
  color: var(--text);
  padding: .3rem .7rem;
  background: var(--surface);
  border: 1px solid var(--border-2);
  border-radius: var(--radius-sm);
}
.how-jail-badge {
  font-size: .76rem;
  color: var(--green);
  padding: .28rem .65rem;
  border: 1px solid var(--green-dim);
  border-radius: var(--radius-sm);
}

/* miniature mmux window: three labeled bordered columns */
.how-mmux {
  display: grid;
  grid-template-columns: .8fr 1.6fr .7fr;
  gap: .65rem;
}
.how-col {
  display: flex;
  flex-direction: column;
  gap: .35rem;
  padding: .65rem;
  min-height: 5.5rem;
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
}
.how-col--main { background: var(--surface-2); }
.how-col--sidebar,
.how-col--panel { background: var(--bg); }
.how-col-label {
  font-size: .7rem;
  font-weight: 600;
  letter-spacing: .05em;
  text-transform: uppercase;
  color: var(--muted);
  margin-bottom: .1rem;
}
.how-row {
  height: .45rem;
  width: 70%;
  background: var(--surface-3);
  border-radius: 2px;
}
.how-row--wide { width: 100%; }
.how-row--active { width: 85%; background: var(--green); }

.how-diagram-caption {
  margin: 1.3rem 0 0;
  font-size: .85rem;
  color: var(--muted);
}

/* the three supporting points */
.how-prose {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 1.4rem;
  max-width: var(--page-max);
}
.how-prose li {
  position: relative;
  padding-left: 1rem;
  font-size: .92rem;
  line-height: 1.65;
  color: var(--text-2);
}
.how-prose li::before {
  content: "▸";
  position: absolute;
  left: 0;
  top: 0;
  color: var(--green);
}
.how-prose em { font-style: normal; color: var(--text); font-weight: 600; }

/* ============================================================================
 * install — single command, brew only
 * ========================================================================== */
#install { text-align: center; }
.install-row {
  display: inline-flex;
  align-items: center;
  gap: .75rem;
  padding: .8rem .8rem .8rem 1.2rem;
  background: var(--surface);
  border: 1px solid var(--border-2);
  border-radius: var(--radius);
  max-width: 100%;
}
.install-row-prompt { color: var(--green); font-weight: 700; }
.install-row-cmd {
  font-size: 1.02rem;
  color: var(--text);
  white-space: nowrap;
  overflow-x: auto;
}
.install-then {
  margin: 1.4rem 0 0;
  color: var(--text-2);
}
.install-then-cmd {
  padding: .12rem .45rem;
  color: var(--green-bright);
  background: var(--surface-2);
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
}
.install-actions {
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
  gap: 1rem;
  margin-top: 2.25rem;
}

/* ============================================================================
 * footer
 * ========================================================================== */
.site-footer {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: center;
  gap: .75rem;
  max-width: var(--page-max);
  margin: 0 auto;
  padding: 3.5rem 1.5rem 4.5rem;
  border-top: 1px solid var(--border);
  color: var(--muted);
  font-size: .9rem;
}
.footer-brand { font-weight: 700; color: var(--text); }
.footer-license { color: var(--muted); }
.footer-sep { color: var(--faint); }
.site-footer a { color: var(--text-2); }
.site-footer a:hover { color: var(--green-bright); }
.footer-caret {
  color: var(--green);
  animation: caret-blink 1.1s steps(1) infinite;
}

/* ============================================================================
 * responsive
 * ========================================================================== */
@media (max-width: 900px) {
  section { padding: 4.5rem 1.25rem; }
  .feature-grid { grid-template-columns: repeat(2, 1fr); }
  .how-prose { grid-template-columns: 1fr; gap: 1rem; }

  /* demo: window over stacked captions; shorter track so it isn't endless */
  #demo { min-height: 680vh; }
  .demo-grid { grid-template-columns: 1fr; gap: 1.75rem; }
  .demo-caption { min-height: 9rem; }

  .tw-panel { display: none !important; }

  .nav-sep { display: none; }
  .nav-links { gap: 1rem; }
}

@media (max-width: 640px) {
  body { font-size: 15px; }
  section { padding: 3.75rem 1rem; }
  .feature-grid { grid-template-columns: 1fr; }

  .tw { height: 26rem; font-size: .76rem; }
  .tw-sidebar { width: 140px; }
  .sb-sub { display: none; }

  .how-mmux { grid-template-columns: 1fr; }

  .nav-links { gap: .8rem; font-size: .85rem; }
  .hero-install,
  .install-row { width: 100%; }
}

@media (max-width: 460px) {
  .tw-sidebar { width: 118px; }
  .demo-caption--static .caption { margin-bottom: 1.6rem; }
}

/* ============================================================================
 * accessibility — focus ring + reduced motion
 * ========================================================================== */
:focus-visible {
  outline: 2px solid var(--green);
  outline-offset: 2px;
  border-radius: var(--radius-sm);
}
.tw:focus-visible {
  outline: none;
  box-shadow: var(--shadow), var(--ring);
}

@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  *,
  *::before,
  *::after {
    animation-duration: .001ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: .001ms !important;
    scroll-behavior: auto !important;
  }
  .hero-caret,
  .footer-caret,
  .screen-cursor { opacity: 1; }
  .scroll-cue { display: none; }
}

/* ============================================================================
 * polish & a11y — themed scrollbars, sr-only announcer
 * ========================================================================== */
.tw-screen,
.tw-panel-screen,
.tw-sidebar {
  scrollbar-width: thin;
  scrollbar-color: var(--surface-3) transparent;
}
.tw-screen::-webkit-scrollbar,
.tw-panel-screen::-webkit-scrollbar,
.tw-sidebar::-webkit-scrollbar { width: 8px; height: 8px; }
.tw-screen::-webkit-scrollbar-thumb,
.tw-panel-screen::-webkit-scrollbar-thumb,
.tw-sidebar::-webkit-scrollbar-thumb { background: var(--surface-3); border-radius: 4px; }
.tw-screen::-webkit-scrollbar-track,
.tw-panel-screen::-webkit-scrollbar-track,
.tw-sidebar::-webkit-scrollbar-track { background: transparent; }

/* visually-hidden live region — tui.js announces sandbox selection/spawn/stop */
.tw-a11y-live {
  position: absolute;
  width: 1px;
  height: 1px;
  margin: -1px;
  padding: 0;
  border: 0;
  overflow: hidden;
  clip: rect(0 0 0 0);
  clip-path: inset(50%);
  white-space: nowrap;
}

main[tabindex="-1"]:focus { outline: none; }

/* sandbox: when the finale is playable, sidebar rows look and behave clickable */
.tw--ready .sb-row { cursor: pointer; }
.tw--ready .sb-row:hover { background: var(--accent-soft); color: var(--text); }
.tw--ready .sb-row--launcher:hover .sb-name,
.tw--ready .sb-row--launcher:hover .sb-plus { color: var(--green-bright); }