/* kernal.one landing page. Same design system as the Outfitter web UI
 * (outfitter/docs/design/README.md): dark = a Commodore 64 screen inside its lighter border,
 * light = early Mac / GEOS paper. Square corners, hard offset shadows, no blur or gradients,
 * phosphor green only for "live". Fonts are self-hosted (OFL-1.1, from @fontsource). */

@font-face { font-family: "Silkscreen"; font-weight: 400; font-display: swap; src: url("/fonts/silkscreen-latin-400-normal.woff2") format("woff2"); }
@font-face { font-family: "Silkscreen"; font-weight: 700; font-display: swap; src: url("/fonts/silkscreen-latin-700-normal.woff2") format("woff2"); }
@font-face { font-family: "IBM Plex Sans"; font-weight: 400; font-display: swap; src: url("/fonts/ibm-plex-sans-latin-400-normal.woff2") format("woff2"); }
@font-face { font-family: "IBM Plex Sans"; font-weight: 600; font-display: swap; src: url("/fonts/ibm-plex-sans-latin-600-normal.woff2") format("woff2"); }
@font-face { font-family: "IBM Plex Mono"; font-weight: 400; font-display: swap; src: url("/fonts/ibm-plex-mono-latin-400-normal.woff2") format("woff2"); }
@font-face { font-family: "IBM Plex Mono"; font-weight: 500; font-display: swap; src: url("/fonts/ibm-plex-mono-latin-500-normal.woff2") format("woff2"); }

:root {
  color-scheme: dark;
  --font-display: "Silkscreen", "Chicago", monospace;
  --font-body: "IBM Plex Sans", -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
  --font-mono: "IBM Plex Mono", ui-monospace, SFMono-Regular, Menlo, monospace;
  --shadow-offset: 3px;

  /* dark: C64 phosphor terminal (default) */
  --frame: #8b7cd8;          /* the C64's lighter border around the screen */
  --frame-alt: #5cff8a;      /* loading-stripe partner colour */
  --bg: #302870;
  --bg-elevated: #3a3184;
  --bg-inset: #251f5c;
  --border: #8b7cd8;
  --text: #e4e0fb;
  --text-dim: #a89fe0;
  --link: #b3a8f0;
  --accent: #7869c4;
  --title-label-text: #ffffff;
  --ok: #5cff8a;
  --ok-contrast: #06210f;
  --scanline-opacity: 0.05;
}

@media (prefers-color-scheme: light) {
  :root:not([data-theme="dark"]) {
    color-scheme: light;
    --frame: #e7ddc6;
    --frame-alt: #2a4b8d;
    --bg: #f1ebdd;
    --bg-elevated: #fffdf8;
    --bg-inset: #e7ddc6;
    --border: #1a1712;
    --text: #171512;
    --text-dim: #5b5548;
    --link: #2a4b8d;
    --accent: #2a4b8d;
    --title-label-text: #fffdf8;
    --ok: #2e6b3e;
    --ok-contrast: #eaf6ec;
    --scanline-opacity: 0;
  }
}

:root[data-theme="light"] {
  color-scheme: light;
  --frame: #e7ddc6;
  --frame-alt: #2a4b8d;
  --bg: #f1ebdd;
  --bg-elevated: #fffdf8;
  --bg-inset: #e7ddc6;
  --border: #1a1712;
  --text: #171512;
  --text-dim: #5b5548;
  --link: #2a4b8d;
  --accent: #2a4b8d;
  --title-label-text: #fffdf8;
  --ok: #2e6b3e;
  --ok-contrast: #eaf6ec;
  --scanline-opacity: 0;
}

* { box-sizing: border-box; }

html, body { margin: 0; }

body {
  min-height: 100vh;
  background: var(--frame);
  color: var(--text);
  font-family: var(--font-body);
  font-size: 16px;
  line-height: 1.55;
  -webkit-font-smoothing: antialiased;
}

/* Faint CRT scanlines, dark mode only. */
body::before {
  content: "";
  position: fixed;
  inset: 0;
  pointer-events: none;
  z-index: 10;
  background: repeating-linear-gradient(to bottom,
    rgba(0, 0, 0, var(--scanline-opacity)) 0, rgba(0, 0, 0, var(--scanline-opacity)) 1px,
    transparent 1px, transparent 3px);
}

::selection { background: var(--accent); color: var(--title-label-text); }

a { color: var(--link); }

:focus-visible { outline: 2px solid var(--ok); outline-offset: 2px; }

/* ---------- the C64 border and screen ---------- */

.border {
  min-height: 100vh;
  padding: clamp(16px, 4vw, 48px);
  background: var(--frame);
}

/* Light mode: the GEOS desktop's 1-bit dither around the paper window. */
:root[data-theme="light"] .border {
  background-image: radial-gradient(#1a1712 1px, transparent 1px), radial-gradient(#1a1712 1px, transparent 1px);
  background-size: 4px 4px;
  background-position: 0 0, 2px 2px;
}
@media (prefers-color-scheme: light) {
  :root:not([data-theme="dark"]) .border {
    background-image: radial-gradient(#1a1712 1px, transparent 1px), radial-gradient(#1a1712 1px, transparent 1px);
    background-size: 4px 4px;
    background-position: 0 0, 2px 2px;
  }
}

/* The cassette-loading flicker: horizontal bars stepping down the border, the way a C64's border
 * strobes while a tape loads. Plays while LOAD is reading from the drive. */
.border.loading {
  background-image: repeating-linear-gradient(to bottom,
    var(--frame) 0, var(--frame) 10px, var(--frame-alt) 10px, var(--frame-alt) 16px,
    var(--accent) 16px, var(--accent) 22px);
  background-size: 100% 44px;
  animation: tape 0.5s steps(4) infinite;
}

@keyframes tape { to { background-position: 0 44px; } }

.screen {
  max-width: 980px;
  color: var(--screen-text, var(--text));
  margin: 0 auto;
  padding: clamp(16px, 4vw, 40px);
  background: var(--bg);
  border: 1px solid var(--border);
  box-shadow: var(--shadow-offset) var(--shadow-offset) 0 0 var(--border);
}

/* ---------- top bar ---------- */

.topbar {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
  padding-bottom: 1rem;
  border-bottom: 1px solid var(--border);
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: 0.6rem;
  color: var(--text);
  text-decoration: none;
}

.mark { color: var(--ok); flex: none; }
.mark .cut { fill: var(--bg); }
.mark .cursor-px { fill: var(--ok); animation: blink 1s steps(2, start) infinite; }

.wordmark {
  font-family: var(--font-display);
  font-size: 1.5rem;
  letter-spacing: 0.12em;
}

.theme-toggle {
  width: 2.25rem;
  height: 2.25rem;
  font-size: 1.1rem;
  line-height: 1;
  color: var(--text);
  background: var(--bg-elevated);
  border: 1px solid var(--border);
  box-shadow: 2px 2px 0 0 var(--border);
  cursor: pointer;
}
.toggles { display: flex; gap: 0.6rem; }
.theme-toggle[aria-pressed="true"] { background: var(--ok); color: var(--ok-contrast); }
.theme-toggle:active { transform: translate(2px, 2px); box-shadow: none; }

/* ---------- boot screen ---------- */

.boot {
  margin: 2rem 0 2.5rem;
  font-family: var(--font-mono);
  font-weight: 500;
  font-size: clamp(0.8rem, 2.6vw, 1.1rem);
  text-transform: uppercase;
  letter-spacing: 0.04em;
  color: var(--screen-text, var(--text));
  container-type: inline-size;
}
.boot p { margin: 0; overflow-wrap: anywhere; }
.boot-banner, .boot-mem { text-align: center; }
.boot-mem { margin-bottom: 1.4em !important; }

/* The command line. A real <input> sits invisibly over the line (so mobile keyboards, paste and
 * screen readers all work); what you see is its echo plus the block cursor, C64 style. */
/* The BASIC screen is 40 columns, like the C64's: the text shrinks on narrow screens so a row
 * (0.64em per character with the letter-spacing) still fits, and PRINT output and the one-line
 * maze wrap where the machine wraps them. Tighter leading lets the maze's diagonals join up. */
.term-out, .term-line { font-size: min(1em, 3.8cqi); line-height: 1.3; }
.term-out p { margin: 0; white-space: pre-wrap; }
.term-prompt { white-space: pre-wrap; }
/* Reverse video (CHR$(18)), e.g. the disk name in LOAD "$" listings. */
.rvs { background: var(--screen-text, var(--text)); color: var(--bg); }
.term-line {
  position: relative;
  min-height: 1.6em;
  cursor: text;
}
.term-echo { white-space: pre-wrap; overflow-wrap: anywhere; }
.term-input {
  position: absolute;
  inset: 0;
  width: 100%;
  opacity: 0;
  font-size: 16px; /* keeps iOS from zooming on focus */
  border: 0;
  padding: 0;
  background: transparent;
  color: transparent;
  caret-color: transparent;
}
.term-line:not(.focused) .cursor { opacity: 0.45; animation: none; }
.term-line.busy .cursor { visibility: hidden; }
.term-stop {
  margin-top: 0.8em;
  padding: 0.2em 0.6em;
  font: inherit;
  font-size: 0.85em;
  color: var(--text);
  background: var(--bg-elevated);
  border: 1px solid var(--border);
  box-shadow: 2px 2px 0 0 var(--border);
  cursor: pointer;
}
.term-stop[hidden] { display: none; }
.term-stop:active { transform: translate(2px, 2px); box-shadow: none; }
.term-hint {
  margin-top: 1.2em !important;
  font-family: var(--font-body);
  font-weight: 400;
  font-size: 0.88rem;
  letter-spacing: 0;
  text-transform: none;
  color: var(--text-dim);
}
kbd {
  font-family: var(--font-mono);
  font-size: 0.95em;
  padding: 0 0.3em;
  background: var(--bg-inset);
  border: 1px solid var(--border);
  white-space: nowrap;
}
.sr-only {
  position: absolute;
  width: 1px;
  height: 1px;
  margin: -1px;
  overflow: hidden;
  clip: rect(0 0 0 0);
  white-space: nowrap;
}

.cursor {
  display: inline-block;
  width: 0.62em;
  height: 1.05em;
  margin-left: 0.1em;
  vertical-align: text-bottom;
  background: var(--ok);
  animation: blink 1s steps(2, start) infinite;
}

@keyframes blink { 50% { opacity: 0; } }

/* After POKE 53281 picks a screen colour the theme's text can't be read on, app.js sets
 * --screen-text (black or white) and this class; the dimmed and link-coloured text on the screen
 * follows it. Panels keep their own background and the theme's text. */
.poked-ink .brand, .poked-ink .tagline, .poked-ink .lede, .poked-ink .term-hint,
.poked-ink .foot, .poked-ink .foot a { color: var(--screen-text); }
.poked-ink kbd { color: var(--text); }   /* on its own --bg-inset chip */

/* ---------- hero ---------- */

h1, h2 {
  font-family: var(--font-display);
  font-weight: 400;
  letter-spacing: 0.02em;
  line-height: 1.3;
}

h1 {
  margin: 0 0 1rem;
  font-size: clamp(1.6rem, 5.2vw, 2.9rem);
}

.tagline {
  max-width: 44rem;
  margin: 0 0 1rem;
  font-family: var(--font-mono);
  font-size: 1.05rem;
  color: var(--link);
}

.lede {
  max-width: 44rem;
  margin: 0 0 1.75rem;
  font-size: 1.08rem;
  color: var(--text);
}


/* ---------- panels ---------- */

.panels {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(min(100%, 340px), 1fr));
  gap: 1.5rem;
  margin: 3rem 0 2.5rem;
}

.panel {
  color: var(--text);
  background: var(--bg-elevated);
  border: 1px solid var(--border);
  box-shadow: var(--shadow-offset) var(--shadow-offset) 0 0 var(--border);
}

/* Striped window title bar with a solid label interrupting it (early Mac / GEOS). */
.panel-title {
  display: flex;
  align-items: center;
  margin: 0;
  padding: 0.3rem 0.5rem;
  min-height: 1.9rem;
  font-size: 0.95rem;
  letter-spacing: 0.06em;
  text-transform: uppercase;
  border-bottom: 1px solid var(--border);
  background: repeating-linear-gradient(to bottom,
    var(--accent) 0, var(--accent) 1px, var(--bg-inset) 1px, var(--bg-inset) 3px);
}
.panel-label {
  padding: 0.15rem 0.45rem;
  background: var(--accent);
  color: var(--title-label-text);
}

.panel-body { padding: 1rem 1.1rem 1.2rem; }
.panel-body p { margin: 0 0 0.9rem; }

code {
  font-family: var(--font-mono);
  font-size: 0.92em;
  padding: 0.05em 0.3em;
  background: var(--bg-inset);
  border: 1px solid var(--border);
}

/* A C64 disk directory listing: block count on the left, description on the right. */
.dir { list-style: none; margin: 0; padding: 0; }
.dir li {
  display: grid;
  grid-template-columns: 7.5rem 1fr;
  gap: 0.75rem;
  padding: 0.45rem 0;
  border-top: 1px dashed var(--border);
}
.blocks {
  font-family: var(--font-display);
  font-size: 0.78rem;
  letter-spacing: 0.06em;
  padding-top: 0.2rem;
  color: var(--text-dim);
}

@media (max-width: 420px) {
  .dir li { grid-template-columns: 1fr; gap: 0.1rem; }
}

/* ---------- footer ---------- */

.foot {
  display: flex;
  flex-wrap: wrap;
  gap: 0.4rem 1.5rem;
  padding-top: 1rem;
  border-top: 1px solid var(--border);
  font-family: var(--font-mono);
  font-size: 0.85rem;
  text-transform: uppercase;
  color: var(--text-dim);
}
.foot .ok { color: var(--ok); }
.foot a { color: var(--text-dim); }

/* ---------- motion ---------- */

@media (prefers-reduced-motion: reduce) {
  body::before { display: none; }
  .cursor, .mark .cursor-px { animation: none; }
  .border.loading { animation: none; }
}