:root {
  --bg: #f6f7f9;
  --surface: #ffffff;
  --text: #111827;
  --muted: #4b5563;
  --border: #e5e7eb;
  --focus: #2563eb;

  --unknown: #6b7280;
  --unknown-bg: #f3f4f6;
  --green: #15803d;
  --green-bg: #ecfdf3;
  --yellow: #b45309;
  --yellow-bg: #fffbeb;
  --red: #b91c1c;
  --red-bg: #fef2f2;

  --notice-text: #1e3a8a;
  --notice-bg: #eff6ff;
  --notice-border: #93c5fd;

  --on-indicator: #ffffff;
  --radius: 20px;

  color-scheme: light dark;
}

@media (prefers-color-scheme: dark) {
  :root {
    --bg: #0f1115;
    --surface: #171a21;
    --text: #f3f4f6;
    --muted: #b6bcc8;
    --border: #2a2f3a;
    --focus: #60a5fa;

    --unknown: #9ca3af;
    --unknown-bg: #1c1f26;
    --green: #22c55e;
    --green-bg: #0f2418;
    --yellow: #f59e0b;
    --yellow-bg: #2a1f0b;
    --red: #f87171;
    --red-bg: #2c1414;

    --notice-text: #bfdbfe;
    --notice-bg: #14213b;
    --notice-border: #3b5b91;

    --on-indicator: #0f1115;
  }
}

*,
*::before,
*::after {
  box-sizing: border-box;
}

html {
  -webkit-text-size-adjust: 100%;
}

body {
  margin: 0;
  min-height: 100vh;
  min-height: 100dvh;
  display: flex;
  flex-direction: column;
  background: var(--bg);
  color: var(--text);
  font-family: system-ui, -apple-system, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
  font-size: 1rem;
  line-height: 1.5;
}

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

/* ---- language toggle ---------------------------------------------------- */

.topbar {
  display: flex;
  justify-content: flex-end;
  padding: 12px 16px 0;
}

.lang {
  display: flex;
  align-items: center;
  gap: 2px;
  color: var(--muted);
  font-size: 0.9rem;
}

.lang button {
  min-width: 44px;
  min-height: 44px;
  padding: 0 8px;
  border: 0;
  border-radius: 8px;
  background: none;
  color: var(--muted);
  font: inherit;
  font-weight: 600;
  letter-spacing: 0.05em;
  cursor: pointer;
}

.lang button[aria-pressed="true"] {
  color: var(--text);
  text-decoration: underline;
  text-underline-offset: 4px;
  text-decoration-thickness: 2px;
}

/* ---- layout ------------------------------------------------------------- */

main {
  flex: 1;
  width: 100%;
  max-width: 640px;
  margin: 0 auto;
  padding: 8px 16px 24px;
}

/* ---- status card -------------------------------------------------------- */

.card {
  --accent: var(--unknown);
  --tint: var(--unknown-bg);

  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: 4px;
  min-height: 60vh;
  min-height: 60dvh;
  padding: 32px 20px;
  border: 2px solid var(--accent);
  border-radius: var(--radius);
  background: var(--tint);
  text-align: center;
}

.card[data-status="green"] {
  --accent: var(--green);
  --tint: var(--green-bg);
}

.card[data-status="yellow"] {
  --accent: var(--yellow);
  --tint: var(--yellow-bg);
}

.card[data-status="red"] {
  --accent: var(--red);
  --tint: var(--red-bg);
}

.indicator {
  display: grid;
  place-items: center;
  width: 120px;
  height: 120px;
  margin-bottom: 16px;
  border-radius: 50%;
  background: var(--accent);
  color: var(--on-indicator);
}

.icon {
  display: none;
  width: 64px;
  height: 64px;
  fill: none;
  stroke: currentColor;
  stroke-width: 2.4;
  stroke-linecap: round;
  stroke-linejoin: round;
}

.icon circle[r="1.1"],
.icon-loading circle {
  fill: currentColor;
  stroke: none;
}

.card[data-status="loading"] .icon-loading,
.card[data-status="unknown"] .icon-unknown,
.card[data-status="green"] .icon-green,
.card[data-status="yellow"] .icon-yellow,
.card[data-status="red"] .icon-red {
  display: block;
}

#headline {
  margin: 0;
  font-size: clamp(1.6rem, 6vw, 2.4rem);
  line-height: 1.2;
  text-wrap: balance;
}

.last-seen {
  margin: 12px 0 0;
  font-size: 1.2rem;
}

.last-seen-exact {
  margin: 0;
  color: var(--muted);
  font-size: 0.95rem;
}

.last-seen:empty,
.last-seen-exact:empty {
  display: none;
}

@media (prefers-reduced-motion: no-preference) {
  .card[data-status="green"] .indicator {
    animation: pulse 2.4s ease-in-out infinite;
  }

  @keyframes pulse {
    0%,
    100% {
      box-shadow: 0 0 0 0 color-mix(in srgb, var(--green) 45%, transparent);
    }
    50% {
      box-shadow: 0 0 0 14px color-mix(in srgb, var(--green) 0%, transparent);
    }
  }
}

/* ---- connectivity notice (deliberately not red) ------------------------- */

.notice {
  display: flex;
  align-items: center;
  gap: 10px;
  margin-top: 16px;
  padding: 12px 16px;
  border: 1px dashed var(--notice-border);
  border-radius: 12px;
  background: var(--notice-bg);
  color: var(--notice-text);
  font-size: 0.95rem;
}

.notice[hidden] {
  display: none;
}

.notice-icon {
  flex: none;
  width: 20px;
  height: 20px;
  fill: none;
  stroke: currentColor;
  stroke-width: 2;
  stroke-linecap: round;
  stroke-linejoin: round;
}

/* ---- history ------------------------------------------------------------ */

.history {
  margin-top: 28px;
}

.history h2 {
  margin: 0 0 8px;
  font-size: 1.1rem;
}

.history ol {
  margin: 0;
  padding: 0;
  list-style: none;
  border: 1px solid var(--border);
  border-radius: 12px;
  background: var(--surface);
  overflow: hidden;
}

.history ol:empty {
  display: none;
}

.history li {
  display: flex;
  flex-wrap: wrap;
  justify-content: space-between;
  gap: 2px 12px;
  padding: 10px 14px;
}

.history li + li {
  border-top: 1px solid var(--border);
}

.history .rel {
  color: var(--muted);
}

.history-empty {
  margin: 0;
  color: var(--muted);
}

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

footer {
  padding: 0 16px 20px;
  color: var(--muted);
  font-size: 0.85rem;
  text-align: center;
}

footer .repo {
  color: inherit;
  text-underline-offset: 3px;
}

footer #updated:not(:empty)::after {
  content: " · ";
}

footer .repo:focus-visible {
  outline: 3px solid var(--focus);
  outline-offset: 2px;
  border-radius: 4px;
}