/*
 * dxg-letterbox-v1 — shell.css
 * Port of the flowmaster-theme-letterbox-v1 foundation tokens and chrome
 * primitives (Editorial Industrial Letterbox) into the dxg- namespace.
 * These are the base primitives the DS composes from; the frozen v1 role
 * classes for DXG components live in components.css.
 *
 * Source theme: ~/.claude/skills/flowmaster-theme-letterbox-v1/SKILL.md
 */

:root {
  /* surfaces */
  --dxg-paper: #FAFAF6;          /* raised cards, primary content */
  --dxg-paper-2: #F3F0E6;        /* page canvas, ambient background */
  --dxg-paper-3: #ECE6D0;        /* dynamic-only — hover, transient highlight */

  /* ink */
  --dxg-ink: #0E0E0C;            /* dark bars, dark slabs, primary text on paper */
  --dxg-ink-soft: #2B2A26;       /* body text on paper */
  --dxg-ink-mute: #6E6B62;       /* secondary text */
  --dxg-ink-faint: #A6A39A;      /* placeholder, tertiary */

  /* dividers */
  --dxg-hairline: #D6CFB6;       /* 1px borders on paper */
  --dxg-hairline-on-ink: rgba(250, 250, 246, 0.16);  /* 1px borders on dark */

  /* accent — scarce */
  --dxg-baobab: #C8102E;         /* the accent: hover invert, focus rings, required marks, error rule */
  --dxg-baobab-bg: #FBE9EC;      /* faintly-tinted baobab background, used rarely */

  /* type */
  --dxg-font-display: "Fraunces", Georgia, serif;
  --dxg-font-ui: "PP Neue Machina", system-ui, sans-serif;
  --dxg-font-mono: "JetBrains Mono", ui-monospace, monospace;
}

/* Letterbox shell — fixed dark bars top + bottom, scrollable body between. */
.dxg-shell-top,
.dxg-shell-bottom {
  position: fixed;
  left: 0;
  right: 0;
  background: var(--dxg-ink);
  z-index: 50;
  display: flex;
  align-items: center;
}

.dxg-shell-top {
  top: 0;
  height: 56px;
  padding: 0 16px;
  border-bottom: 1px solid var(--dxg-hairline-on-ink);
  gap: 16px;
}

.dxg-shell-bottom {
  bottom: 0;
  height: 40px;
  padding: 0 16px;
  /* 2026-07-29 (round-7 UX finding): the bar is dark ink, so its text must
     use an ON-DARK token. `.dxg-mono`'s default `--dxg-ink-soft` is a
     dark-on-light value and measured ~1.4:1 here — illegible. */
  color: var(--dxg-paper-3);
  border-top: 1px solid var(--dxg-hairline-on-ink);
  gap: 12px;
}

.dxg-shell-body {
  padding-top: 56px;
  padding-bottom: 40px;
  min-height: 100vh;
  background: var(--dxg-paper-2);
  color: var(--dxg-ink-soft);
  font-family: var(--dxg-font-ui);
}

/* Brand wordmark — typeset, not a logo. */
.dxg-brand {
  font-family: var(--dxg-font-display);
  font-style: italic;
  font-weight: 700;
  font-size: 18px;
  color: var(--dxg-paper);
  letter-spacing: -0.01em;
  line-height: 1;
  text-decoration: none;
}
.dxg-brand b { font-style: normal; font-weight: 900; }
.dxg-brand i { font-style: italic; font-weight: 700; }
.dxg-brand-mini { font-size: 12px; }

/* Buttons — four variants, snap-invert on hover. */
.dxg-btn {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 7px 12px;
  border-radius: 4px;
  font-family: var(--dxg-font-ui);
  font-weight: 600;
  font-size: 12px;
  letter-spacing: 0.02em;
  cursor: pointer;
  transition: all 0.14s ease;
  text-decoration: none;
  border: 1px solid transparent;
  line-height: 1;
  white-space: nowrap;
}
.dxg-btn:disabled { cursor: not-allowed; opacity: 0.5; }

.dxg-btn-primary {
  background: var(--dxg-ink);
  color: var(--dxg-paper);
  border-color: var(--dxg-ink);
}
.dxg-btn-primary:hover:not(:disabled) { background: var(--dxg-baobab); border-color: var(--dxg-baobab); }

.dxg-btn-ghost {
  background: transparent;
  color: var(--dxg-ink);
  border-color: var(--dxg-ink);
}
.dxg-btn-ghost:hover:not(:disabled) { background: var(--dxg-ink); color: var(--dxg-paper); }

.dxg-btn-primary-on-dark {
  background: var(--dxg-paper);
  color: var(--dxg-ink);
  border-color: var(--dxg-paper);
}
.dxg-btn-primary-on-dark:hover:not(:disabled) { background: var(--dxg-baobab); color: var(--dxg-paper); border-color: var(--dxg-baobab); }

.dxg-btn-ghost-on-dark {
  background: transparent;
  color: var(--dxg-paper);
  border-color: var(--dxg-paper);
}
.dxg-btn-ghost-on-dark:hover:not(:disabled) { background: var(--dxg-paper); color: var(--dxg-ink); }

/* Card on beige canvas. */
.dxg-card {
  background: var(--dxg-paper);
  border: 1px solid var(--dxg-hairline);
  border-radius: 4px;
  padding: 16px;
}

/* Eyebrows + mono ids. */
.dxg-eyebrow {
  font-family: var(--dxg-font-mono);
  font-weight: 500;
  font-size: 10px;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--dxg-ink-mute);
}

.dxg-mono {
  font-family: var(--dxg-font-mono);
  font-weight: 500;
  font-size: 11px;
  letter-spacing: 0.04em;
  color: var(--dxg-ink-soft);
}
/* On the dark shell bars, inherit the bar's own on-dark colour. */
.dxg-shell-bottom .dxg-mono,
.dxg-shell-top .dxg-mono { color: inherit; }
.dxg-mono-hash { color: var(--dxg-baobab); margin-right: 1px; }

/* Hard rule ported verbatim: no drop shadows, no rounded corners above 4px. */
*:focus-visible {
  outline: 2px solid var(--dxg-baobab);
  outline-offset: 2px;
  border-radius: 2px;
}

/* Wordmark-as-link (2026-07-29): identical look whether span or anchor. */
a.dxg-brand {
  /* Link affordance only — NEVER color (2026-07-29 round-6 UX finding:
     `color: inherit` overrode .dxg-brand's own paper color and rendered the
     wordmark near-black on the near-black bar). */
  text-decoration: none;
}