/* ============================================================
   MRBD Design System  ·  v1
   Shared foundation for Meta Ray-Ban Display web apps.
   Target: 600x600 additive waveguide display, D-pad navigation.

   This file is the canonical source. Each app under apps/ keeps
   an identical copy named design-system.css so it stays
   self-contained and Vercel-deployable on its own.
   ============================================================ */

:root {
  /* --- Surfaces (#000 renders transparent on the waveguide) --- */
  --bg-primary:   #000000;
  --bg-secondary: #0c0c14;
  --bg-tertiary:  #16161f;
  --bg-card:      #1c1c2b;

  /* --- Text (size + weight carry hierarchy, not low-contrast grays) --- */
  --text-primary:   #ffffff;
  --text-secondary: #b6b6c6;
  --text-muted:     #80808f;

  /* --- Accent + status --- */
  --accent:     #00d4ff;
  --accent-ink: #04141a;
  --success:    #2fe39a;
  --warning:    #ffcc45;
  --danger:     #ff4d6a;

  /* --- Focus ring (must read against a bright real-world background) --- */
  --focus-ring: #00d4ff;
  --focus-glow: rgba(0, 212, 255, 0.5);

  /* --- Radius --- */
  --radius-sm:   10px;
  --radius-md:   16px;
  --radius-lg:   24px;
  --radius-pill: 999px;

  /* --- Layout --- */
  --safe: 40px;   /* keep content off the frame edge; optics dim there */
  --gap:  16px;

  /* --- Type scale (large on purpose: the display sits small in the FOV) --- */
  --fs-display: 96px;   /* hero readouts */
  --fs-hero:    64px;
  --fs-h1:      34px;
  --fs-h2:      26px;
  --fs-body:    22px;
  --fs-label:   18px;   /* smallest readable size */

  --font-sans: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;

  --ease: cubic-bezier(0.22, 1, 0.36, 1);
}

* { margin: 0; padding: 0; box-sizing: border-box; }

html, body { width: 600px; height: 600px; }

body {
  font-family: var(--font-sans);
  background: var(--bg-primary);
  color: var(--text-primary);
  overflow: hidden;
  -webkit-font-smoothing: antialiased;
}

#app { position: relative; width: 100%; height: 100%; }

.hidden { display: none !important; }

/* --- Screen: a full-viewport view --- */
.screen {
  position: absolute;
  inset: 0;
  display: flex;
  flex-direction: column;
}

/* --- Header --- */
.ds-header {
  display: flex;
  align-items: center;
  gap: 14px;
  flex-shrink: 0;
  padding: 28px var(--safe) 12px;
}
.ds-header h1 {
  flex: 1;
  font-size: var(--fs-h1);
  font-weight: 700;
  letter-spacing: 0.5px;
}
.ds-header .ds-meta {
  font-size: var(--fs-label);
  font-weight: 600;
  color: var(--text-secondary);
  text-transform: uppercase;
  letter-spacing: 1.5px;
}

/* --- Content area --- */
.ds-content {
  flex: 1;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: var(--gap);
  padding: 8px var(--safe);
  overflow-y: auto;
}

/* --- Focusable + focus ring (D-pad navigation target) --- */
.focusable {
  border: 3px solid transparent;
  border-radius: var(--radius-md);
  outline: none;
  cursor: pointer;
  transition: border-color 0.12s var(--ease),
              box-shadow 0.12s var(--ease),
              transform 0.12s var(--ease),
              background-color 0.12s var(--ease);
}
.focusable:focus {
  border-color: var(--focus-ring);
  box-shadow: 0 0 24px var(--focus-glow);
  transform: scale(1.03);
}

/* --- Button --- */
.ds-btn {
  min-height: 64px;
  padding: 18px 22px;
  font-family: inherit;
  font-size: var(--fs-body);
  font-weight: 600;
  color: var(--text-primary);
  background: var(--bg-tertiary);
  text-align: center;
}
.ds-btn.primary { background: var(--accent); color: var(--accent-ink); }
.ds-btn.danger  { background: var(--danger);  color: #1a0007; }

/* --- Nav bar: a row of actions pinned to the bottom --- */
.ds-nav {
  display: flex;
  gap: 12px;
  flex-shrink: 0;
  padding: 12px var(--safe) 28px;
}
.ds-nav .ds-btn { flex: 1; }

/* --- Card: a labelled value block --- */
.ds-card {
  padding: 28px 36px;
  background: var(--bg-card);
  border-radius: var(--radius-lg);
  text-align: center;
}
.ds-card-label {
  margin-bottom: 8px;
  font-size: var(--fs-label);
  color: var(--text-secondary);
  text-transform: uppercase;
  letter-spacing: 2px;
}
.ds-card-value {
  font-size: var(--fs-hero);
  font-weight: 800;
  line-height: 1;
  color: var(--accent);
}

/* --- Tile: a launcher entry (reserved for the upcoming gallery grid) --- */
.ds-tile {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 8px;
  padding: 20px 12px;
  background: var(--bg-card);
  border-radius: var(--radius-md);
}
.ds-tile-icon { font-size: 44px; line-height: 1; }
.ds-tile-name {
  font-size: var(--fs-label);
  font-weight: 600;
  text-align: center;
}

/* --- Hint text --- */
.ds-hint {
  font-size: var(--fs-label);
  line-height: 1.45;
  color: var(--text-muted);
  text-align: center;
}

/* --- Utilities --- */
.ds-stack {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: var(--gap);
}
.text-success { color: var(--success); }
.text-warning { color: var(--warning); }
.text-danger  { color: var(--danger); }