:root {
  color-scheme: light dark;
  --bg: #f7f6f3;
  --surface: #ffffff;
  --ink: #18181b;
  --muted: #71717a;
  --line: #e4e2db;
  --line-strong: #d4d1c8;
  --accent: #18181b;
  --accent-fg: #fafafa;
  --focus: #3f3f46;
  --ok: #3f6212;
  --err: #9f1239;
  --warn: #a16207;
  --radius: 10px;
  --font: "SF Pro Text", "Segoe UI", system-ui, -apple-system, sans-serif;
  --mono: "SF Mono", "JetBrains Mono", "Fira Code", ui-monospace, Menlo, Consolas, monospace;
  --shadow: 0 1px 0 rgba(24, 24, 27, 0.04);
}

@media (prefers-color-scheme: dark) {
  :root {
    --bg: #0c0c0e;
    --surface: #141416;
    --ink: #f4f4f5;
    --muted: #a1a1aa;
    --line: #27272a;
    --line-strong: #3f3f46;
    --accent: #f4f4f5;
    --accent-fg: #18181b;
    --focus: #d4d4d8;
    --ok: #a3e635;
    --err: #fb7185;
    --warn: #fbbf24;
    --shadow: 0 1px 0 rgba(0, 0, 0, 0.35);
  }
}

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

html,
body {
  height: 100%;
}

body {
  margin: 0;
  color: var(--ink);
  background:
    radial-gradient(1200px 500px at 50% -120px, color-mix(in srgb, var(--line) 55%, transparent), transparent),
    var(--bg);
  font-family: var(--font);
  font-size: 14px;
  line-height: 1.5;
  -webkit-font-smoothing: antialiased;
}

.page {
  max-width: 1180px;
  margin: 0 auto;
  min-height: 100%;
  padding: 28px 20px 24px;
  display: grid;
  grid-template-rows: auto 1fr auto;
  gap: 18px;
}

.header {
  display: flex;
  align-items: flex-end;
  justify-content: space-between;
  gap: 16px;
  flex-wrap: wrap;
}

.brand h1 {
  margin: 0;
  font-size: 22px;
  font-weight: 650;
  letter-spacing: -0.03em;
}

.tagline {
  margin: 4px 0 0;
  color: var(--muted);
  font-size: 13px;
}

.controls {
  display: flex;
  align-items: center;
  gap: 8px;
}

.seg {
  display: inline-flex;
  padding: 3px;
  border: 1px solid var(--line);
  border-radius: 999px;
  background: var(--surface);
  box-shadow: var(--shadow);
}

.seg-btn {
  appearance: none;
  border: 0;
  background: transparent;
  color: var(--muted);
  font: inherit;
  font-size: 13px;
  font-weight: 550;
  padding: 7px 14px;
  border-radius: 999px;
  cursor: pointer;
  transition: background 0.12s ease, color 0.12s ease;
}

.seg-btn:hover {
  color: var(--ink);
}

.seg-btn.is-active {
  background: var(--accent);
  color: var(--accent-fg);
}

.btn {
  appearance: none;
  border: 1px solid var(--line);
  background: var(--surface);
  color: var(--ink);
  font: inherit;
  font-weight: 550;
  border-radius: 8px;
  padding: 8px 12px;
  cursor: pointer;
  box-shadow: var(--shadow);
  transition: border-color 0.12s ease, background 0.12s ease;
}

.btn:hover {
  border-color: var(--line-strong);
}

.btn:focus-visible,
.seg-btn:focus-visible,
textarea:focus-visible {
  outline: 2px solid var(--focus);
  outline-offset: 2px;
}

.btn.ghost {
  background: transparent;
  box-shadow: none;
}

.btn.sm {
  padding: 4px 8px;
  font-size: 12px;
  font-weight: 500;
  color: var(--muted);
}

.btn.sm:hover {
  color: var(--ink);
}

.panels {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 14px;
  min-height: 0;
}

.panel {
  min-height: 0;
  display: grid;
  grid-template-rows: auto 1fr;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: var(--surface);
  box-shadow: var(--shadow);
  overflow: hidden;
}

.panel-bar {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 12px;
  padding: 10px 12px;
  border-bottom: 1px solid var(--line);
}

.panel-bar label {
  font-size: 12px;
  font-weight: 600;
  letter-spacing: 0.04em;
  text-transform: uppercase;
  color: var(--muted);
}

.panel-actions {
  display: flex;
  gap: 4px;
}

textarea {
  width: 100%;
  height: 100%;
  min-height: 420px;
  border: 0;
  resize: none;
  padding: 14px 14px 18px;
  background: transparent;
  color: var(--ink);
  font-family: var(--mono);
  font-size: 13px;
  line-height: 1.55;
  tab-size: 2;
}

textarea::placeholder {
  color: color-mix(in srgb, var(--muted) 80%, transparent);
}

#output {
  color: color-mix(in srgb, var(--ink) 92%, var(--muted));
}

.footer {
  display: flex;
  align-items: baseline;
  justify-content: space-between;
  gap: 12px;
  flex-wrap: wrap;
  color: var(--muted);
  font-size: 12px;
}

.status {
  margin: 0;
  min-height: 1.2em;
}

.status.is-ok {
  color: var(--ok);
}

.status.is-err {
  color: var(--err);
}

.status.is-warn {
  color: var(--warn);
}

.meta {
  margin: 0;
}

@media (max-width: 860px) {
  .page {
    padding: 18px 14px 16px;
  }

  .panels {
    grid-template-columns: 1fr;
  }

  textarea {
    min-height: 280px;
  }
}

@media (max-width: 480px) {
  .brand h1 {
    font-size: 20px;
  }

  .seg-btn {
    padding: 7px 10px;
    font-size: 12px;
  }
}