:root {
  --bg: #0f1115;
  --bg-elev: #181b22;
  --bg-input: #11141a;
  --border: #262a33;
  --border-strong: #353a47;
  --text: #e6e8eb;
  --text-dim: #9aa3ad;
  --text-muted: #6b7382;
  --accent: #6aa5ff;
  --accent-strong: #4d8cff;
  --info: #79c0ff;
  --warning: #ffb454;
  --error: #ff6b6b;
  --success: #7ed957;
  --mono: ui-monospace, SFMono-Regular, "SF Mono", Menlo, Consolas, "Liberation Mono", monospace;
  --sans: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;

  /* Diagram tokens — separate from main theme so we can ensure contrast
     against the strategy-card background in both light and dark modes. */
  --diagram-node-fill: #11141a;
  --diagram-node-stroke: #353a47;
  --diagram-active-fill: rgba(106, 165, 255, 0.18);
  --diagram-target-fill: rgba(106, 165, 255, 0.42);
  --diagram-good-fill: rgba(126, 217, 87, 0.18);
  --diagram-bad-fill: rgba(255, 107, 107, 0.18);
}

[data-theme="light"] {
  --bg: #fafbfc;
  --bg-elev: #ffffff;
  --bg-input: #ffffff;
  --border: #e1e4e8;
  --border-strong: #c8ccd1;
  --text: #1f2328;
  --text-dim: #5a6470;
  --text-muted: #8b95a1;
  --accent: #2f6ad9;
  --accent-strong: #1f56be;
  --info: #1f6feb;
  --warning: #b45309;
  --error: #cf222e;
  --success: #1a7f37;

  /* Light-mode diagrams: subtle gray nodes on white, blue accent fills */
  --diagram-node-fill: #f0f3f7;
  --diagram-node-stroke: #c8ccd1;
  --diagram-active-fill: rgba(47, 106, 217, 0.10);
  --diagram-target-fill: rgba(47, 106, 217, 0.28);
  --diagram-good-fill: rgba(26, 127, 55, 0.12);
  --diagram-bad-fill: rgba(207, 34, 46, 0.10);
}

* { box-sizing: border-box; }

html, body {
  margin: 0;
  padding: 0;
  background: var(--bg);
  color: var(--text);
  font-family: var(--sans);
  font-size: 15px;
  line-height: 1.5;
}

.container {
  max-width: 1080px;
  margin: 0 auto;
  padding: 0 24px;
}

/* Header */

.site-header {
  border-bottom: 1px solid var(--border);
  background: linear-gradient(180deg, var(--bg-elev) 0%, var(--bg) 100%);
}

.header-row {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 16px 24px;
}

.logo {
  display: flex;
  align-items: baseline;
  gap: 8px;
  text-decoration: none;
  color: var(--text);
  font-weight: 600;
  font-size: 18px;
}

.logo-mark {
  font-size: 22px;
  color: var(--accent);
}

.logo-tld {
  color: var(--text-muted);
  font-weight: 400;
}

.site-nav button {
  background: transparent;
  border: 1px solid var(--border);
  color: var(--text-dim);
  padding: 6px 12px;
  border-radius: 6px;
  cursor: pointer;
  font-family: inherit;
  font-size: 13px;
}

.site-nav button:hover {
  border-color: var(--border-strong);
  color: var(--text);
}

.hero {
  padding: 24px 24px 32px;
}

.hero h1 {
  font-size: 28px;
  font-weight: 600;
  margin: 0 0 8px;
}

.tagline {
  margin: 0;
  color: var(--text-dim);
  font-size: 16px;
}

/* App layout */

.app {
  padding-top: 24px;
  padding-bottom: 32px;
}

.controls {
  display: flex;
  align-items: center;
  gap: 12px;
  padding: 12px 0;
  flex-wrap: wrap;
}

.controls label {
  color: var(--text-dim);
  font-size: 13px;
}

.controls select {
  background: var(--bg-input);
  color: var(--text);
  border: 1px solid var(--border);
  padding: 8px 10px;
  border-radius: 6px;
  font-family: inherit;
  font-size: 14px;
  cursor: pointer;
}

button.primary, button.ghost {
  background: transparent;
  border: 1px solid var(--border);
  color: var(--text);
  padding: 8px 14px;
  border-radius: 6px;
  font-family: inherit;
  font-size: 14px;
  font-weight: 500;
  cursor: pointer;
  transition: all 0.12s;
}

button.primary {
  background: var(--accent);
  color: white;
  border-color: var(--accent);
}

button.primary:hover {
  background: var(--accent-strong);
  border-color: var(--accent-strong);
}

button.ghost:hover {
  border-color: var(--border-strong);
  background: var(--bg-elev);
}

button.small {
  padding: 4px 10px;
  font-size: 12px;
}

button:disabled {
  opacity: 0.5;
  cursor: not-allowed;
}

.rate-limit {
  margin-left: auto;
  display: inline-flex;
  align-items: baseline;
  gap: 6px;
  color: var(--text-muted);
  font-size: 13px;
  font-family: var(--mono);
}

.rate-limit-label {
  text-transform: uppercase;
  letter-spacing: 0.05em;
  font-size: 11px;
  color: var(--text-muted);
}

.rate-limit.exhausted #rate-limit-value {
  color: var(--error);
}

/* Panels */

.panels {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 16px;
  margin-bottom: 16px;
}

@media (max-width: 900px) {
  .panels { grid-template-columns: 1fr; }
}

.panel {
  background: var(--bg-elev);
  border: 1px solid var(--border);
  border-radius: 8px;
  overflow: hidden;
  display: flex;
  flex-direction: column;
  min-height: 480px;
}

.panel-header {
  display: flex;
  align-items: center;
  gap: 12px;
  padding: 10px 14px;
  border-bottom: 1px solid var(--border);
  background: var(--bg);
}

.panel-header h2 {
  margin: 0;
  font-size: 13px;
  font-weight: 600;
  color: var(--text-dim);
  text-transform: uppercase;
  letter-spacing: 0.05em;
}

.byte-count {
  margin-left: auto;
  color: var(--text-muted);
  font-size: 12px;
  font-family: var(--mono);
}

.tabs .tab-buttons {
  display: flex;
  gap: 4px;
  margin-left: auto;
}

.tabs button#copy-btn {
  margin-left: 8px;
}

.tab {
  background: transparent;
  border: 1px solid transparent;
  color: var(--text-muted);
  padding: 4px 10px;
  font-size: 12px;
  font-family: inherit;
  border-radius: 4px;
  cursor: pointer;
}

.tab.active {
  color: var(--text);
  background: var(--bg-elev);
  border-color: var(--border);
}

.tab:hover:not(.active) {
  color: var(--text-dim);
}

.tab-content {
  flex: 1;
  display: flex;
}

.tab-content.hidden {
  display: none;
}

textarea#sql-input {
  flex: 1;
  width: 100%;
  background: var(--bg-input);
  color: var(--text);
  border: none;
  resize: vertical;
  padding: 14px;
  font-family: var(--mono);
  font-size: 13.5px;
  line-height: 1.55;
  outline: none;
  min-height: 440px;
}

#output {
  flex: 1;
  margin: 0;
  padding: 14px;
  background: var(--bg-input);
  font-family: var(--mono);
  font-size: 13.5px;
  line-height: 1.55;
  overflow: auto;
  color: var(--text);
  white-space: pre;
}

#output code {
  font-family: inherit;
  color: inherit;
}

.ast-tree {
  flex: 1;
  padding: 14px;
  background: var(--bg-input);
  font-family: var(--mono);
  font-size: 13px;
  overflow: auto;
  color: var(--text-dim);
}

.ast-node {
  margin-left: 14px;
  border-left: 1px solid var(--border);
  padding-left: 10px;
}

.ast-key {
  color: var(--accent);
}

.ast-type {
  color: var(--warning);
  font-weight: 600;
}

.ast-value {
  color: var(--success);
}

.ast-toggle {
  cursor: pointer;
  user-select: none;
  color: var(--text-muted);
}

/* Status / findings */

.status-bar {
  padding: 10px 14px;
  border-radius: 6px;
  margin-bottom: 14px;
  font-size: 14px;
  border: 1px solid var(--border);
  background: var(--bg-elev);
}

.status-bar.ok {
  border-color: var(--success);
  color: var(--success);
}

.status-bar.error {
  border-color: var(--error);
  color: var(--error);
}

.status-bar.warning {
  border-color: var(--warning);
  color: var(--warning);
}

.status-bar.hidden {
  display: none;
}

.results h2 {
  font-size: 14px;
  font-weight: 600;
  color: var(--text-dim);
  text-transform: uppercase;
  letter-spacing: 0.05em;
  margin: 24px 0 12px;
}

.findings {
  list-style: none;
  padding: 0;
  margin: 0;
  display: flex;
  flex-direction: column;
  gap: 10px;
}

.finding {
  background: var(--bg-elev);
  border: 1px solid var(--border);
  border-left: 4px solid var(--info);
  border-radius: 6px;
  padding: 12px 14px;
}

.finding.warning { border-left-color: var(--warning); }
.finding.error { border-left-color: var(--error); }
.finding.info { border-left-color: var(--info); }

.finding-header {
  display: flex;
  align-items: center;
  gap: 10px;
  margin-bottom: 6px;
}

.severity-badge {
  font-size: 11px;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  padding: 2px 6px;
  border-radius: 4px;
  font-weight: 600;
}

.severity-badge.warning {
  background: rgba(255, 180, 84, 0.15);
  color: var(--warning);
}

.severity-badge.error {
  background: rgba(255, 107, 107, 0.15);
  color: var(--error);
}

.severity-badge.info {
  background: rgba(121, 192, 255, 0.15);
  color: var(--info);
}

.finding-title {
  font-weight: 600;
  color: var(--text);
}

.finding-message {
  color: var(--text-dim);
  margin: 4px 0 8px;
}

.finding-snippet {
  font-family: var(--mono);
  font-size: 12.5px;
  background: var(--bg);
  border: 1px solid var(--border);
  padding: 6px 10px;
  border-radius: 4px;
  color: var(--text-dim);
  white-space: pre-wrap;
  word-break: break-word;
}

.empty {
  color: var(--text-muted);
  padding: 14px;
  background: var(--bg-elev);
  border: 1px dashed var(--border);
  border-radius: 6px;
  text-align: center;
}

/* Footer */

.site-footer {
  border-top: 1px solid var(--border);
  margin-top: 48px;
  padding: 24px 0;
  color: var(--text-muted);
  font-size: 13px;
}

.site-footer a {
  color: var(--text-dim);
}

.site-footer p {
  margin: 4px 0;
}

.site-footer .privacy {
  margin-top: 12px;
}

.site-footer .meta {
  margin-top: 12px;
  font-family: var(--mono);
  font-size: 12px;
}

/* About / SEO content section */

.about {
  margin: 64px auto 32px;
  padding-top: 32px;
  border-top: 1px solid var(--border);
  color: var(--text-dim);
  font-size: 15px;
  line-height: 1.65;
  max-width: 920px;
}

.about h2 {
  font-size: 20px;
  font-weight: 600;
  color: var(--text);
  text-transform: none;
  letter-spacing: 0;
  margin: 32px 0 12px;
}

.about h2:first-of-type {
  margin-top: 0;
}

.about p {
  margin: 0 0 12px;
}

.about ul {
  margin: 8px 0 16px;
  padding-left: 22px;
}

.about li {
  margin-bottom: 6px;
}

.about strong {
  color: var(--text);
  font-weight: 600;
}

.about code {
  font-family: var(--mono);
  font-size: 0.92em;
  background: var(--bg-elev);
  padding: 1px 6px;
  border-radius: 4px;
  color: var(--accent);
}

.about a {
  color: var(--accent);
  text-decoration: none;
}

.about a:hover {
  text-decoration: underline;
}

.faq {
  margin: 12px 0 0;
}

.faq dt {
  font-weight: 600;
  color: var(--text);
  margin-top: 16px;
}

.faq dd {
  margin: 4px 0 0;
  padding: 0;
}

/* Strategies chapter — illustrated content */

.about h3 {
  font-size: 17px;
  font-weight: 600;
  color: var(--text);
  margin: 28px 0 10px;
}

.strategy {
  display: grid;
  grid-template-columns: 400px 1fr;
  grid-template-areas:
    "figure text"
    "code   code";
  column-gap: 32px;
  row-gap: 16px;
  align-items: start;
  margin: 28px 0 36px;
  padding: 20px;
  background: var(--bg-elev);
  border: 1px solid var(--border);
  border-radius: 8px;
}

@media (max-width: 800px) {
  .strategy {
    grid-template-columns: 1fr;
    grid-template-areas:
      "figure"
      "text"
      "code";
    gap: 16px;
  }
}

.strategy-figure {
  grid-area: figure;
}

.strategy-text {
  grid-area: text;
  min-width: 0;
}

.strategy-text h4 {
  margin: 0 0 8px;
  font-size: 17px;
  font-weight: 600;
  color: var(--text);
}

.strategy-text p {
  margin: 0 0 12px;
  color: var(--text-dim);
}

.strategy-code {
  grid-area: code;
  background: var(--bg);
  border: 1px solid var(--border);
  border-radius: 6px;
  padding: 12px 14px;
  margin: 0;
  overflow-x: auto;
  font-family: var(--mono);
  font-size: 12.5px;
  line-height: 1.55;
  color: var(--text-dim);
  /* macOS hides overflow scrollbars by default; nudge it visible when needed. */
  scrollbar-width: thin;
}

.strategy-code code {
  color: inherit;
  background: transparent;
  padding: 0;
}

.strategy-code::-webkit-scrollbar {
  height: 8px;
}

.strategy-code::-webkit-scrollbar-thumb {
  background: var(--border-strong);
  border-radius: 4px;
}

/* Inline SVG diagrams — themed via CSS variables so they invert in light mode */

.diagram {
  width: 100%;
  height: auto;
  display: block;
  font-family: var(--sans);
}

.diagram .dnode {
  fill: var(--diagram-node-fill);
  stroke: var(--diagram-node-stroke);
  stroke-width: 1;
}

.diagram .dnode-active {
  fill: var(--diagram-active-fill);
  stroke: var(--accent);
  stroke-width: 1.25;
}

.diagram .dnode-target {
  fill: var(--diagram-target-fill);
}

.diagram .dnode-good {
  fill: var(--diagram-good-fill);
  stroke: var(--success);
  stroke-width: 1.25;
}

.diagram .dnode-bad {
  fill: var(--diagram-bad-fill);
  stroke: var(--error);
  stroke-width: 1.25;
}

.diagram .darrow-line {
  stroke: var(--border-strong);
  stroke-width: 1.25;
  fill: none;
}

.diagram .darrow-line-active {
  stroke: var(--accent);
  stroke-width: 1.5;
}

.diagram .darrow-line-good {
  stroke: var(--success);
  stroke-width: 1.5;
}

.diagram .darrow-line-bad {
  stroke: var(--error);
  stroke-width: 1.5;
}

.diagram .dsep {
  stroke: var(--border);
  stroke-width: 1;
  stroke-dasharray: 3 4;
}

.diagram .dlabel {
  font-size: 11px;
  fill: var(--text);
}

.diagram .dlabel-strong {
  font-size: 12px;
  font-weight: 600;
  fill: var(--text);
}

.diagram .dlabel-dim {
  font-size: 10.5px;
  fill: var(--text-muted);
}

.diagram .dlabel-good {
  font-size: 11px;
  font-weight: 600;
  fill: var(--success);
}

.diagram .dlabel-bad {
  font-size: 11px;
  font-weight: 600;
  fill: var(--error);
}

/* Header nav links */

.nav-link {
  color: var(--text-dim);
  text-decoration: none;
  padding: 6px 12px;
  border-radius: 6px;
  font-size: 13px;
  border: 1px solid transparent;
}

.nav-link:hover {
  color: var(--text);
  border-color: var(--border);
}

.nav-link-active {
  color: var(--text);
  border-color: var(--border);
  background: var(--bg-elev);
}