:root {
  color-scheme: light;
  --bg: #f4f6f7;
  --panel: #ffffff;
  --ink: #17201b;
  --muted: #5f6b62;
  --line: #d7ddd3;
  --accent: #0f7b63;
  --accent-ink: #ffffff;
  --warn: #a43f2b;
  --code-bg: #101816;
  --code-ink: #e9f2ed;
  --focus: #246bfe;
  font-family: Inter, ui-sans-serif, system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
  line-height: 1.5;
}

* {
  box-sizing: border-box;
}

body {
  min-height: 100vh;
  margin: 0;
  color: var(--ink);
  background:
    linear-gradient(180deg, rgba(255, 255, 255, 0.9), rgba(244, 246, 247, 0.96)),
    var(--bg);
}

a {
  color: inherit;
}

.topbar {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
  min-height: 4rem;
  padding: 0 1.5rem;
  border-bottom: 1px solid var(--line);
  background: rgba(255, 255, 255, 0.78);
  backdrop-filter: blur(18px);
}

.brand {
  font-weight: 700;
  text-decoration: none;
}

nav {
  display: flex;
  gap: 1rem;
  color: var(--muted);
  font-size: 0.95rem;
}

nav a {
  text-decoration: none;
}

nav a:hover {
  color: var(--ink);
}

.playground {
  display: grid;
  grid-template-columns: minmax(0, 1.35fr) minmax(22rem, 0.65fr);
  gap: 1rem;
  width: min(96rem, calc(100vw - 2rem));
  min-height: calc(100vh - 6rem);
  margin: 1rem auto;
}

.pane {
  display: flex;
  flex-direction: column;
  min-width: 0;
  min-height: 0;
  border: 1px solid var(--line);
  border-radius: 8px;
  background: var(--panel);
  box-shadow: 0 18px 45px rgba(23, 32, 27, 0.08);
  overflow: hidden;
}

.pane-header {
  display: flex;
  align-items: flex-start;
  justify-content: space-between;
  gap: 1rem;
  padding: 1rem 1rem 0.75rem;
  border-bottom: 1px solid var(--line);
}

.eyebrow {
  margin: 0 0 0.15rem;
  color: var(--accent);
  font-size: 0.72rem;
  font-weight: 800;
  text-transform: uppercase;
}

h1,
h2 {
  margin: 0;
  font-size: clamp(1.25rem, 2.2vw, 1.7rem);
  line-height: 1.2;
}

h2 {
  font-size: 1.15rem;
}

.status {
  flex: 0 0 auto;
  max-width: 12rem;
  padding: 0.35rem 0.55rem;
  border: 1px solid var(--line);
  border-radius: 999px;
  color: var(--muted);
  font-size: 0.82rem;
  font-weight: 700;
  text-align: center;
  white-space: nowrap;
}

.status[data-tone="ok"] {
  color: var(--accent);
  border-color: rgba(15, 123, 99, 0.35);
  background: rgba(15, 123, 99, 0.08);
}

.status[data-tone="error"] {
  color: var(--warn);
  border-color: rgba(164, 63, 43, 0.35);
  background: rgba(164, 63, 43, 0.08);
}

.toolbar {
  display: flex;
  align-items: end;
  flex-wrap: wrap;
  gap: 0.6rem;
  padding: 0.85rem 1rem;
  border-bottom: 1px solid var(--line);
  background: #f8faf9;
}

.field {
  display: grid;
  gap: 0.25rem;
  min-width: min(16rem, 100%);
}

.field span {
  color: var(--muted);
  font-size: 0.78rem;
  font-weight: 700;
}

select,
button {
  min-height: 2.35rem;
  border: 1px solid var(--line);
  border-radius: 7px;
  font: inherit;
}

select {
  width: 100%;
  padding: 0.35rem 2rem 0.35rem 0.55rem;
  color: var(--ink);
  background: #ffffff;
}

button {
  padding: 0.35rem 0.8rem;
  color: var(--accent-ink);
  background: var(--accent);
  border-color: var(--accent);
  font-weight: 750;
  cursor: pointer;
}

button.secondary {
  color: var(--ink);
  background: #ffffff;
  border-color: var(--line);
}

button:hover {
  filter: brightness(0.96);
}

select:focus,
button:focus,
textarea:focus {
  outline: 3px solid rgba(36, 107, 254, 0.22);
  outline-offset: 2px;
  border-color: var(--focus);
}

textarea {
  flex: 1 1 auto;
  width: 100%;
  min-height: 28rem;
  padding: 1rem;
  border: 0;
  resize: none;
  color: var(--code-ink);
  background: var(--code-bg);
  font: 0.95rem/1.55 ui-monospace, SFMono-Regular, Menlo, Consolas, "Liberation Mono", monospace;
  tab-size: 2;
}

.output-pane {
  background: #fbfbfc;
}

.results-list {
  display: grid;
  gap: 0.6rem;
  margin: 0;
  padding: 1rem 1rem 0.5rem 2.5rem;
}

.results-list li {
  padding: 0.65rem 0.75rem;
  border: 1px solid var(--line);
  border-radius: 7px;
  background: #ffffff;
  font: 1rem/1.35 ui-monospace, SFMono-Regular, Menlo, Consolas, "Liberation Mono", monospace;
}

.results-list .empty-result {
  color: var(--muted);
  font-family: inherit;
}

.diagnostics {
  margin: 0.5rem 1rem 1rem;
  padding: 0.85rem;
  border: 1px solid rgba(164, 63, 43, 0.3);
  border-radius: 7px;
  overflow: auto;
  color: #47180f;
  background: #fff5f1;
  font: 0.86rem/1.45 ui-monospace, SFMono-Regular, Menlo, Consolas, "Liberation Mono", monospace;
  white-space: pre-wrap;
}

@media (max-width: 900px) {
  .playground {
    grid-template-columns: 1fr;
    width: min(100vw - 1rem, 56rem);
  }

  .output-pane {
    min-height: 18rem;
  }
}

@media (max-width: 560px) {
  .topbar {
    align-items: flex-start;
    flex-direction: column;
    padding: 0.85rem 1rem;
  }

  .playground {
    width: 100%;
    margin: 0;
    gap: 0;
  }

  .pane {
    border-left: 0;
    border-right: 0;
    border-radius: 0;
  }

  .pane-header,
  .toolbar {
    padding-left: 0.8rem;
    padding-right: 0.8rem;
  }

  .toolbar > button {
    flex: 1 1 8rem;
  }

  textarea {
    min-height: 24rem;
    font-size: 0.88rem;
  }
}