:root {
  --bg: #f4f5f7;
  --card-bg: #ffffff;
  --text: #1f2933;
  --muted: #6b7280;
  --primary: #2563eb;
  --border: #d1d5db;
  --shadow: 0 20px 40px rgba(15, 23, 42, 0.08);
  --active-node-bg: color-mix(in srgb, var(--primary) 14%, transparent);
  --token-highlight-bg: color-mix(in srgb, var(--primary) 18%, transparent);
  --token-highlight-border: color-mix(in srgb, var(--primary) 55%, transparent);
  --syntax-keyword: #ff0000;
  --syntax-operator: #ff0000;
  --syntax-comment: #008000;
  --syntax-constant: #000000;
  --syntax-default: #0000ff;
}

body.theme-dark {
  --bg: #0f172a;
  --card-bg: #111827;
  --text: #e5e7eb;
  --muted: #9ca3af;
  --primary: #60a5fa;
  --border: #334155;
  --shadow: 0 20px 40px rgba(2, 6, 23, 0.5);
  --active-node-bg: color-mix(in srgb, var(--primary) 22%, transparent);
  --token-highlight-bg: color-mix(in srgb, var(--primary) 28%, transparent);
  --token-highlight-border: color-mix(in srgb, var(--primary) 65%, transparent);
  --syntax-constant: #cbd5e1;
}

* {
  box-sizing: border-box;
}

body {
  margin: 0;
  font-family: Inter, system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
  background: var(--bg);
  color: var(--text);
  line-height: 1.6;
}

.page {
  min-height: 100vh;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 32px 16px;
}

.card {
  width: min(1100px, 100%);
  background: var(--card-bg);
  padding: 32px;
  border-radius: 16px;
  box-shadow: var(--shadow);
  display: flex;
  flex-direction: column;
  gap: 24px;
}

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

.card h1 {
  margin: 0;
  font-size: 24px;
}

label {
  font-weight: 500;
}

textarea,
input[type="file"] {
  width: 100%;
  padding: 12px 14px;
  margin-top: 8px;
  border-radius: 10px;
  border: 1px solid var(--border);
  background: transparent;
  color: inherit;
  font: inherit;
}

textarea:focus,
input[type="file"]:focus {
  outline: 2px solid color-mix(in srgb, var(--primary) 70%, transparent);
  border-color: var(--primary);
}

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 12px 20px;
  border-radius: 10px;
  border: 1px solid transparent;
  background: var(--primary);
  color: #fff;
  font-weight: 600;
  cursor: pointer;
  width: 100%;
  text-decoration: none;
  transition: transform 0.2s ease, box-shadow 0.2s ease, background 0.2s ease;
}

.btn:hover {
  transform: translateY(-1px);
  box-shadow: 0 8px 16px rgba(37, 99, 235, 0.2);
}

.btn-secondary {
  background: transparent;
  color: var(--text);
  border-color: var(--border);
}

.btn-secondary:hover {
  box-shadow: 0 8px 16px rgba(15, 23, 42, 0.1);
}

.divider {
  display: flex;
  align-items: center;
  gap: 12px;
  text-transform: uppercase;
  font-size: 12px;
  letter-spacing: 0.12em;
  color: var(--muted);
}

.divider::before,
.divider::after {
  content: "";
  flex: 1;
  height: 1px;
  background: var(--border);
}

pre {
  margin: 0;
  padding: 16px;
  border-radius: 12px;
  background: color-mix(in srgb, var(--card-bg) 70%, var(--bg));
  color: inherit;
  font-family: "SFMono-Regular", Menlo, Monaco, Consolas, "Liberation Mono", "Courier New", monospace;
  font-size: 14px;
  overflow: auto;
  border: 1px solid var(--border);
  tab-size: 4;
  -moz-tab-size: 4;
}

.result-layout {
  display: grid;
  grid-template-columns: minmax(220px, 280px) minmax(0, 1fr);
  grid-template-areas:
    "tree code";
  gap: 24px;
  align-items: start;
}

.tree-panel {
  grid-area: tree;
  display: flex;
  flex-direction: column;
}

.code-panel {
  grid-area: code;
  min-width: 0;
}

.tree-card {
  border: 1px solid var(--border);
  border-radius: 12px;
  padding: 12px 16px;
  background: color-mix(in srgb, var(--card-bg) 85%, var(--bg));
}

.tree-card h2 {
  margin: 0 0 12px;
  font-size: 16px;
}

.tree-section {
  display: flex;
  flex-direction: column;
  gap: 8px;
  margin-bottom: 12px;
}

.tree-section:last-child {
  margin-bottom: 0;
}

.tree-section h3 {
  margin: 0;
  font-size: 14px;
  color: var(--muted);
}

.tree-list {
  list-style: none;
  padding: 0;
  margin: 0;
  display: flex;
  flex-direction: column;
  gap: 8px;
}

.tree-list-nested {
  margin-top: 8px;
  padding-left: 16px;
  border-left: 1px dashed var(--border);
}

.tree-item {
  display: flex;
  flex-direction: column;
  gap: 8px;
}

.tree-details {
  display: flex;
  flex-direction: column;
  gap: 8px;
}

.tree-summary {
  list-style: none;
  display: flex;
  gap: 8px;
  align-items: stretch;
  cursor: pointer;
}

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

.tree-toggle {
  width: 18px;
  min-width: 18px;
  border-radius: 6px;
  border: 1px solid color-mix(in srgb, var(--primary) 45%, var(--border));
  background: color-mix(in srgb, var(--primary) 24%, var(--card-bg));
  color: var(--text);
  font-size: 0;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  flex-shrink: 0;
  padding: 4px 2px;
  box-shadow: 0 4px 10px rgba(15, 23, 42, 0.14);
  outline: 1px solid transparent;
  transition: transform 0.2s ease, color 0.2s ease, border-color 0.2s ease, background 0.2s ease, box-shadow 0.2s ease;
}

.tree-toggle::before {
  content: "▸";
  font-size: 12px;
  line-height: 1;
  font-weight: 700;
}

.tree-details[open] .tree-toggle {
  color: var(--primary);
  border-color: var(--primary);
  background: color-mix(in srgb, var(--primary) 30%, var(--card-bg));
  box-shadow: 0 6px 14px rgba(37, 99, 235, 0.25);
}

.tree-details[open] .tree-toggle::before {
  content: "▾";
}

.tree-summary:hover .tree-toggle {
  background: color-mix(in srgb, var(--primary) 28%, var(--card-bg));
  border-color: color-mix(in srgb, var(--primary) 55%, var(--border));
  box-shadow: 0 6px 16px rgba(37, 99, 235, 0.2);
}

.tree-summary:focus-visible .tree-toggle {
  outline-color: color-mix(in srgb, var(--primary) 65%, transparent);
  box-shadow: 0 0 0 3px color-mix(in srgb, var(--primary) 35%, transparent);
}

.tree-node {
  display: flex;
  flex-direction: column;
  gap: 6px;
  padding: 8px;
  border-radius: 10px;
  border: 1px solid transparent;
  background: color-mix(in srgb, var(--card-bg) 80%, var(--bg));
  cursor: pointer;
}

.tree-node.is-active {
  border-color: var(--primary);
  background: var(--active-node-bg);
  box-shadow: 0 0 0 2px color-mix(in srgb, var(--primary) 25%, transparent);
}

.tree-input {
  width: 100%;
  border: 1px solid var(--border);
  border-radius: 8px;
  padding: 6px 8px;
  font: inherit;
  background: transparent;
  color: inherit;
}

.tree-original {
  font-size: 12px;
  color: var(--muted);
}

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

.token {
  border-radius: 4px;
  box-decoration-break: clone;
  -webkit-box-decoration-break: clone;
}

.token-keyword {
  color: var(--syntax-keyword);
}

.token-operator {
  color: var(--syntax-operator);
}

.token-comment {
  color: var(--syntax-comment);
}

.token-constant {
  color: var(--syntax-constant);
}

.token-default {
  color: var(--syntax-default);
}

.token-mapped-var,
.token-mapped-func {
  background: transparent;
  padding: 0;
}

.variable-color-default .token-mapped-var,
.variable-color-default .token-mapped-func {
  color: var(--syntax-default);
}

.token-highlight {
  background: var(--token-highlight-bg);
  box-shadow: inset 0 0 0 1px var(--token-highlight-border);
}

.switch {
  position: relative;
  display: inline-flex;
  align-items: center;
  gap: 8px;
  font-size: 14px;
  color: var(--muted);
}

.switch input {
  position: absolute;
  opacity: 0;
  width: 0;
  height: 0;
}

.slider {
  position: relative;
  width: 44px;
  height: 24px;
  background: var(--border);
  border-radius: 999px;
  transition: background 0.2s ease;
}

.slider::after {
  content: "";
  position: absolute;
  width: 18px;
  height: 18px;
  left: 3px;
  top: 3px;
  background: var(--card-bg);
  border-radius: 50%;
  transition: transform 0.2s ease;
}

.switch input:checked + .slider {
  background: var(--primary);
}

.switch input:checked + .slider::after {
  transform: translateX(20px);
}

.switch-text {
  font-size: 13px;
  color: var(--muted);
}

.form-group {
  display: flex;
  flex-direction: column;
  gap: 8px;
}

.actions {
  display: flex;
  flex-direction: column;
  gap: 12px;
}

.settings {
  border: 1px solid var(--border);
  border-radius: 12px;
  padding: 12px 16px;
  background: color-mix(in srgb, var(--card-bg) 85%, var(--bg));
}

.settings summary {
  cursor: pointer;
  font-weight: 600;
}

.settings-body {
  margin-top: 12px;
  display: flex;
  flex-direction: column;
  gap: 12px;
}

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

.color-grid {
  display: grid;
  grid-template-columns: minmax(0, 1fr) auto auto;
  gap: 10px 12px;
  align-items: center;
}

.color-grid label {
  font-weight: 500;
}

.color-grid input[type="color"] {
  width: 48px;
  height: 32px;
  padding: 0;
  border: 1px solid var(--border);
  border-radius: 8px;
  background: var(--card-bg);
}

.color-reset {
  width: 32px;
  height: 32px;
  border-radius: 8px;
  border: 1px solid var(--border);
  background: color-mix(in srgb, var(--card-bg) 85%, var(--bg));
  color: var(--muted);
  display: inline-flex;
  align-items: center;
  justify-content: center;
  cursor: pointer;
  padding: 0;
  position: relative;
  transition: color 0.2s ease, border-color 0.2s ease, background 0.2s ease, box-shadow 0.2s ease;
}

.color-reset::before {
  content: "⟲";
  font-size: 15px;
  line-height: 1;
}

.color-reset::after {
  content: attr(data-tooltip);
  position: absolute;
  bottom: calc(100% + 8px);
  right: 0;
  background: var(--text);
  color: var(--card-bg);
  font-size: 11px;
  padding: 4px 8px;
  border-radius: 6px;
  white-space: nowrap;
  opacity: 0;
  transform: translateY(4px);
  pointer-events: none;
  transition: opacity 0.2s ease, transform 0.2s ease;
}

.color-reset:hover,
.color-reset:focus-visible {
  color: var(--primary);
  border-color: color-mix(in srgb, var(--primary) 55%, var(--border));
  box-shadow: 0 6px 14px rgba(37, 99, 235, 0.2);
}

.color-reset:hover::after,
.color-reset:focus-visible::after {
  opacity: 1;
  transform: translateY(0);
}

.checkbox {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  font-weight: 500;
}

.checkbox input {
  width: 16px;
  height: 16px;
}

@media (max-width: 600px) {
  .card {
    padding: 24px;
  }

  .card-header {
    flex-direction: column;
    align-items: flex-start;
  }

  .result-layout {
    grid-template-columns: minmax(0, 1fr);
    grid-template-areas:
      "tree"
      "code";
  }

  .tree-panel {
    width: 100%;
  }
}