/* Espresso Algorithm house style, shared by every page of the site.
 *
 * The coffee series shares one look: latte-web uses the same structure with
 * lighter colours. Base element styles live in the `espresso-site` cascade
 * layer, so any style a page writes itself wins whatever its specificity.
 * Colours are custom properties with a light and a dark set; the canvas
 * pages read them at draw time, so bars follow the theme too.
 */

@layer espresso-site {
  :root {
    color-scheme: light dark;
    --esp-bg: #faf6f1;
    --esp-fg: #2a1a10;
    --esp-muted: #6b5344;
    --esp-accent: #7a3e1d;
    --esp-accent-fg: #fff8f0;
    --esp-card: #ffffff;
    --esp-line: #e6d9ca;
    --esp-code: #f2e9df;
    --esp-focus: #c26a35;
    /* Bars and graphs: the resting bar, a read, a write, and finished. */
    --esp-bar: #9a6a4b;
    --esp-read: #d49a4e;
    --esp-write: #b3321c;
    --esp-done: #4f7a45;
    --esp-font:
      system-ui, -apple-system, 'Segoe UI', Roboto, 'PingFang SC',
      'Noto Sans SC', sans-serif;
    --esp-mono: ui-monospace, SFMono-Regular, Menlo, Consolas, monospace;
  }

  @media (prefers-color-scheme: dark) {
    :root {
      --esp-bg: #16100c;
      --esp-fg: #f2e7dc;
      --esp-muted: #bca796;
      --esp-accent: #e3a56d;
      --esp-accent-fg: #1a110b;
      --esp-card: #201712;
      --esp-line: #3b2c21;
      --esp-code: #2a1f18;
      --esp-focus: #f0b27a;
      --esp-bar: #a9805f;
      --esp-read: #f0c27e;
      --esp-write: #ff7b5c;
      --esp-done: #9ccd88;
    }
  }

  html {
    background: var(--esp-bg);
  }

  body {
    font: 17px/1.6 var(--esp-font);
    color: var(--esp-fg);
    background: var(--esp-bg);
  }

  h1 {
    margin: 1.25rem 0 0.75rem;
    font-size: 2rem;
    line-height: 1.2;
    letter-spacing: -0.01em;
  }

  h2 {
    margin: 1.75rem 0 0.5rem;
    font-size: 1.3rem;
    line-height: 1.3;
  }

  p {
    margin: 0.5rem 0 1rem;
  }

  a {
    color: var(--esp-accent);
    text-underline-offset: 0.15em;
  }

  code,
  kbd,
  pre {
    font-family: var(--esp-mono);
    font-size: 0.9em;
  }

  code {
    padding: 0.1em 0.35em;
    border-radius: 0.3em;
    background: var(--esp-code);
  }

  pre {
    padding: 0.9rem 1rem;
    overflow-x: auto;
    border-radius: 0.5rem;
    background: var(--esp-code);
  }

  pre code {
    padding: 0;
    background: none;
  }

  button,
  input,
  select,
  textarea {
    font: inherit;
  }

  button {
    padding: 0.4rem 0.95rem;
    border: 1px solid var(--esp-accent);
    border-radius: 0.5rem;
    background: var(--esp-accent);
    color: var(--esp-accent-fg);
    cursor: pointer;
  }

  button.ghost {
    background: transparent;
    color: var(--esp-accent);
  }

  button:hover {
    filter: brightness(1.08);
  }

  button:disabled {
    opacity: 0.55;
    cursor: not-allowed;
  }

  select,
  textarea,
  input:not([type='range']) {
    padding: 0.35rem 0.55rem;
    border: 1px solid var(--esp-line);
    border-radius: 0.4rem;
    background: var(--esp-card);
    color: var(--esp-fg);
  }

  input[type='range'] {
    accent-color: var(--esp-accent);
  }

  :focus-visible {
    outline: 3px solid var(--esp-focus);
    outline-offset: 2px;
  }

  .lead {
    margin-top: -0.25rem;
    font-size: 1.05rem;
  }

  .muted {
    color: var(--esp-muted);
  }

  /* Read by screen readers, not shown. */
  .sr-only {
    position: absolute;
    width: 1px;
    height: 1px;
    overflow: hidden;
    clip-path: inset(50%);
    white-space: nowrap;
  }

  .chip {
    display: inline-block;
    padding: 0.15rem 0.6rem;
    border-radius: 999px;
    background: var(--esp-code);
    color: var(--esp-muted);
    font-size: 0.85rem;
    text-decoration: none;
  }

  .chip.live {
    background: var(--esp-accent);
    color: var(--esp-accent-fg);
    font-weight: 600;
  }

  .panel {
    padding: 1rem 1.1rem;
    border: 1px solid var(--esp-line);
    border-radius: 0.8rem;
    background: var(--esp-card);
  }

  footer {
    margin-top: 3.5rem;
    padding-top: 1.25rem;
    border-top: 1px solid var(--esp-line);
    color: var(--esp-muted);
    font-size: 0.9rem;
  }
}

/* One language at a time: language.js sets data-language on <html>, and the
 * other language's elements disappear. Only hiding is needed, so every
 * element keeps the display its page gives it. */
:root:not([data-language='zh']) [data-l='zh'],
:root[data-language='zh'] [data-l='en'] {
  display: none !important;
}

/* The page frame and the top bar are unlayered, so no page reset can move
 * them; a page's own body rules still win, because they come later. */
body {
  max-width: 64rem;
  margin: 0 auto;
  padding: 0 1.25rem 3rem;
}

.esp-bar {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 0.35rem 1rem;
  margin: 0 0 1rem;
  padding: 0.8rem 0;
  border-bottom: 1px solid var(--esp-line);
  font: 600 0.9rem/1.4 system-ui, -apple-system, 'Segoe UI', sans-serif;
  letter-spacing: 0.01em;
}

.esp-bar a {
  color: var(--esp-accent);
  text-decoration: none;
}

.esp-bar a:hover {
  text-decoration: underline;
}

/* A small espresso cup: crema on top of the shot. */
.esp-bar .esp-home::before {
  content: '';
  display: inline-block;
  width: 0.95em;
  height: 0.8em;
  margin-right: 0.45em;
  vertical-align: -0.05em;
  border-radius: 0.15em 0.15em 0.45em 0.45em;
  background: linear-gradient(#d49a4e 0 30%, #3b2416 30% 100%);
  box-shadow: inset 0 0 0 1.5px var(--esp-fg);
}

.esp-bar .esp-crumb {
  color: var(--esp-muted);
  font-weight: 500;
}

.esp-bar .esp-links {
  display: flex;
  align-items: center;
  gap: 1rem;
  margin-left: auto;
}

/* The language switch looks like the links next to it. */
.esp-bar .esp-language {
  padding: 0.1rem 0.55rem;
  border: 1px solid var(--esp-line);
  border-radius: 999px;
  background: transparent;
  color: var(--esp-accent);
  font: inherit;
  cursor: pointer;
}

.esp-bar .esp-language:hover {
  border-color: var(--esp-accent);
  filter: none;
}