:root {
  color-scheme: light dark;
  --bg: #f5f7fb;
  --card-bg: #ffffff;
  --border: rgba(15, 23, 42, 0.08);
  --accent: #2563eb;
  --accent-hover: #1d4ed8;
  --text: #0f172a;
  --muted: rgba(15, 23, 42, 0.6);
  --shadow: 0 16px 40px rgba(15, 23, 42, 0.12);
  --radius-lg: 16px;
  --radius-md: 12px;
  font-family: 'Inter', system-ui, -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
}

* {
  box-sizing: border-box;
}

body {
  margin: 0;
  background: radial-gradient(circle at top, rgba(37, 99, 235, 0.15), transparent 70%), var(--bg);
  color: var(--text);
  min-height: 100vh;
  display: flex;
  justify-content: center;
  padding: 48px 16px 64px;
}

.page {
  width: min(1100px, 100%);
  display: grid;
  gap: 32px;
}

.card {
  background: var(--card-bg);
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow);
  padding: 32px clamp(24px, 3vw, 48px);
  border: 1px solid var(--border);
}

.card__eyebrow {
  text-transform: uppercase;
  font-size: 12px;
  font-weight: 600;
  color: var(--accent);
  letter-spacing: 0.12em;
}

.card__title {
  margin: 8px 0 12px;
  font-size: clamp(28px, 5vw, 36px);
  font-weight: 700;
}

.card__subtitle {
  margin: 0;
  color: var(--muted);
  font-size: 16px;
  max-width: 560px;
}

.form {
  margin-top: 32px;
  display: grid;
  gap: 24px;
}

.form__row {
  display: grid;
  gap: 8px;
}

.form__label {
  font-weight: 600;
  font-size: 14px;
}

.form__input {
  padding: 14px 16px;
  border-radius: var(--radius-md);
  border: 1px solid var(--border);
  background: rgba(255, 255, 255, 0.9);
  font-size: 15px;
  transition: border-color 160ms ease, box-shadow 160ms ease;
}

.form__input:focus {
  outline: none;
  border-color: var(--accent);
  box-shadow: 0 0 0 3px rgba(37, 99, 235, 0.2);
}

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

.divider {
  position: relative;
  text-align: center;
  font-size: 12px;
  text-transform: uppercase;
  letter-spacing: 0.2em;
  color: var(--muted);
}

.divider::before,
.divider::after {
  content: '';
  position: absolute;
  top: 50%;
  width: 40%;
  height: 1px;
  background: var(--border);
}

.divider::before {
  left: 0;
}

.divider::after {
  right: 0;
}

.form__actions {
  display: flex;
  gap: 12px;
  flex-wrap: wrap;
}

.code-samples {
  margin-top: 32px;
  display: grid;
  gap: 20px;
}

.code-samples__header {
  display: grid;
  gap: 6px;
}

.code-samples__eyebrow {
  text-transform: uppercase;
  letter-spacing: 0.2em;
  font-size: 11px;
  font-weight: 600;
  color: var(--accent);
}

.code-samples__title {
  margin: 0;
  font-size: 20px;
  font-weight: 600;
}

.code-samples__note {
  margin: 0;
  color: var(--muted);
  font-size: 14px;
}

.code-samples__grid {
  display: grid;
  gap: 16px;
  grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
}

.code-block {
  background: rgba(15, 23, 42, 0.05);
  border: 1px solid rgba(15, 23, 42, 0.08);
  border-radius: var(--radius-md);
  padding: 18px;
  display: grid;
  gap: 10px;
}

.code-block__title {
  margin: 0;
  font-size: 15px;
  font-weight: 600;
  color: var(--text);
}

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

.code-block__pre {
  margin: 0;
  background: rgba(15, 23, 42, 0.86);
  color: #f8fafc;
  border-radius: 12px;
  padding: 12px 14px;
  overflow-x: auto;
  font-family: 'JetBrains Mono', ui-monospace, SFMono-Regular, Menlo, Monaco, Consolas, monospace;
  font-size: 12px;
  line-height: 1.5;
}

.code-block__pre code {
  display: block;
  white-space: pre;
}

.button {
  padding: 12px 20px;
  border-radius: 999px;
  border: none;
  background: var(--accent);
  color: #fff;
  font-weight: 600;
  cursor: pointer;
  transition: background 160ms ease, transform 160ms ease;
}

.button:hover {
  background: var(--accent-hover);
  transform: translateY(-1px);
}

.button:disabled {
  background: rgba(37, 99, 235, 0.45);
  cursor: not-allowed;
  transform: none;
}

.button--ghost {
  background: rgba(37, 99, 235, 0.08);
  color: var(--accent);
}

.button--sm {
  padding: 8px 14px;
  font-size: 13px;
}

.results {
  background: rgba(255, 255, 255, 0.72);
  border-radius: var(--radius-lg);
  border: 1px solid var(--border);
  padding: 24px clamp(20px, 5vw, 40px);
  box-shadow: var(--shadow);
}

.results__header {
  display: flex;
  justify-content: space-between;
  align-items: flex-start;
  gap: 16px;
  flex-wrap: wrap;
  margin-bottom: 16px;
}

.results__title {
  margin: 0;
  font-size: 20px;
  font-weight: 600;
}

.results__subtitle {
  margin: 4px 0 0;
  font-size: 14px;
  color: var(--muted);
  max-width: 620px;
}

.results__buttons {
  display: flex;
  gap: 8px;
  flex-wrap: wrap;
}

.results__tree {
  font-family: 'JetBrains Mono', ui-monospace, SFMono-Regular, Menlo, Monaco, Consolas, monospace;
  font-size: 13px;
  background: rgba(15, 23, 42, 0.08);
  color: var(--text);
  padding: 16px;
  border-radius: var(--radius-md);
  border: 1px solid var(--border);
  max-height: 540px;
  overflow: auto;
  display: grid;
  gap: 8px;
}

.tree__branch {
  background: rgba(255, 255, 255, 0.75);
  border-radius: 10px;
  border: 1px solid rgba(15, 23, 42, 0.06);
}

.tree__branch > summary {
  list-style: none;
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 12px;
  padding: 10px 14px;
  cursor: pointer;
  font-weight: 600;
}

.tree__branch > summary::-webkit-details-marker {
  display: none;
}

.tree__summary-key {
  color: var(--text);
}

.tree__summary-meta {
  font-size: 12px;
  color: var(--muted);
}

.tree__children {
  padding: 8px 14px 16px 22px;
  display: grid;
  gap: 6px;
  border-left: 1px dashed rgba(15, 23, 42, 0.08);
}

.tree__row {
  display: flex;
  gap: 12px;
  align-items: flex-start;
  padding: 6px 10px;
  background: rgba(37, 99, 235, 0.05);
  border-radius: 8px;
}

.tree__key {
  font-weight: 600;
  color: var(--accent);
  min-width: fit-content;
}

.tree__value {
  margin: 0;
  font-family: inherit;
  white-space: pre-wrap;
  word-break: break-word;
  color: var(--text);
}

.tree__value--wrap {
  word-break: break-all;
  max-height: 220px;
  overflow: auto;
  padding-right: 4px;
}

.tree__empty {
  font-style: italic;
  font-size: 12px;
  color: var(--muted);
  padding-left: 6px;
}

.placeholder {
  text-align: center;
  color: var(--muted);
}

.toast {
  border: none;
  border-radius: var(--radius-md);
  padding: 14px 18px;
  background: rgba(220, 38, 38, 0.18);
  color: #991b1b;
  font-weight: 600;
}

@media (max-width: 720px) {
  body {
    padding: 24px 12px 48px;
  }

  .page {
    gap: 24px;
  }

  .form__actions {
    flex-direction: column;
  }

  .button,
  .button--ghost {
    width: 100%;
  }

  .code-samples__grid {
    grid-template-columns: 1fr;
  }

  .results__buttons {
    width: 100%;
    justify-content: flex-start;
  }
}