/* Design-system tokens plus the button and input components the app uses.
   The palette is a dark neutral ramp and a single accent; spacing, radius, and
   elevation are token scales. Everything app-specific is built on top of these
   in app.css. Fonts are vendored locally; see fonts/fonts.css (linked from
   index.html). */

:root {
  --color-bg: #161826;
  --color-surface: #232532;
  --color-text: #e9e9ed;
  --color-accent: #9184d9;
  --color-divider: color-mix(in srgb, #e9e9ed 16%, transparent);

  /* Neutral ramp, one shared lightness scale. */
  --color-neutral-100: #f3f5fe;
  --color-neutral-200: #e4e7f5;
  --color-neutral-300: #cfd3e5;
  --color-neutral-400: #b2b6ca;
  --color-neutral-500: #9397ab;
  --color-neutral-600: #75798c;
  --color-neutral-700: #595d6c;
  --color-neutral-800: #3f424d;
  --color-neutral-900: #292b31;

  /* Accent ramp. */
  --color-accent-100: #f5f4ff;
  --color-accent-200: #e7e5fe;
  --color-accent-300: #d2cefd;
  --color-accent-400: #b5abfc;
  --color-accent-500: #968ae0;
  --color-accent-600: #796cbf;
  --color-accent-700: #5d5294;
  --color-accent-800: #423a6a;
  --color-accent-900: #2b2741;

  --font-heading: "Inter", system-ui, sans-serif;
  --font-heading-weight: 500;
  --font-body: "Inter", system-ui, sans-serif;

  --space-1: 2.8px;
  --space-2: 5.6px;
  --space-3: 8.4px;
  --space-4: 11.2px;
  --space-6: 16.8px;
  --space-8: 22.4px;

  --radius-sm: 4px;
  --radius-md: 8px;
  --radius-lg: 14px;

  /* App surfaces that sit just off the page background. Tokens rather than
     literals so the light theme can move them (see light.css). */
  --color-panel: #1a1c29;   /* control panel gradient + its sticky toolbar */
  --color-glow: #20222f;    /* centre of the viewer's backdrop wash */
  --color-card: #1b1d2b;    /* floating schematic card, and its canvas */

  --shadow-md: 0 0 0 1px #595d6c, 0 6px 18px rgba(0,0,0,0.55);
  --shadow-lg: 0 0 0 1px #9397ab, 0 16px 40px rgba(0,0,0,0.65);
}

*, *::before, *::after { box-sizing: border-box; }
body { margin: 0; font-size: 15px; line-height: 1.55; font-weight: 400; }
:focus { outline: none; }
:focus-visible { outline: 2px solid var(--color-accent); outline-offset: 2px; }

/* Buttons */
.btn {
  display: inline-flex; align-items: center; justify-content: center; gap: 6px;
  cursor: pointer; text-decoration: none;
  font-family: var(--font-heading); font-weight: var(--font-heading-weight);
  font-size: 14px; line-height: 1.2; color: var(--color-text);
  background: transparent; border: 1px solid transparent;
  padding: var(--space-2) calc(var(--space-3) * 1.2);
  border-radius: var(--radius-md);
}
.btn:disabled { opacity: 0.45; cursor: not-allowed; }
.btn-primary { color: var(--color-accent); border-color: var(--color-accent); }
.btn-primary:hover { background: color-mix(in srgb, var(--color-accent) 12%, transparent); }
.btn-primary:active { background: color-mix(in srgb, var(--color-accent) 22%, transparent); }
.btn-secondary { border-color: var(--color-divider); }
.btn-secondary:hover { background: color-mix(in srgb, var(--color-text) 7%, transparent); }
.btn-secondary:active { background: color-mix(in srgb, var(--color-text) 14%, transparent); }
.btn-ghost { color: var(--color-accent); padding-inline: var(--space-1); }
.btn-ghost:hover { background: color-mix(in srgb, var(--color-accent) 10%, transparent); }
.btn-ghost:active { background: color-mix(in srgb, var(--color-accent) 18%, transparent); }
.btn-icon { width: 36px; height: 36px; padding: 0; }

/* Inputs */
.input {
  width: 100%; min-height: 36px; padding: 6px 10px; font: inherit;
  font-size: 14px; color: var(--color-text); caret-color: var(--color-accent);
  background: var(--color-surface);
  border: 1px solid var(--color-divider); border-radius: var(--radius-md);
}
.input:hover { border-color: color-mix(in srgb, var(--color-text) 45%, transparent); }
.input:focus-visible { border-color: var(--color-accent); outline-offset: 0; }