:root {
  --bg: #0e1116;
  --panel: #161b22;
  --panel-2: #1c2230;
  --border: #2a3140;
  --text: #e6edf3;
  --muted: #8b98a9;
  --green: #2ea043;
  --green-soft: rgba(46, 160, 67, 0.22);
  --red: #d9534f;
  --red-soft: rgba(217, 83, 79, 0.22);
  --accent: #ffb703;
  --accent-soft: rgba(255, 183, 3, 0.16);
  --match: rgba(88, 166, 255, 0.28);
  --match-line: #58a6ff;
  --radius: 10px;
  --mono: ui-monospace, SFMono-Regular, "SF Mono", Menlo, Consolas, "Liberation Mono", monospace;
  --sans: system-ui, -apple-system, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
}

* {
  box-sizing: border-box;
}

body {
  margin: 0;
  font-family: var(--sans);
  background: var(--bg);
  color: var(--text);
  line-height: 1.5;
}

/* ---------- top bar ---------- */
.topbar {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  padding: 16px 24px;
  border-bottom: 1px solid var(--border);
  flex-wrap: wrap;
}
.brand {
  display: flex;
  align-items: center;
  gap: 14px;
}
.logo {
  font-size: 34px;
  color: var(--accent);
  line-height: 1;
}
.brand h1 {
  font-size: 20px;
  margin: 0;
  letter-spacing: 0.2px;
}
.tagline {
  margin: 0;
  color: var(--muted);
  font-size: 13px;
}
.topbar-actions {
  display: flex;
  gap: 8px;
}

/* ---------- buttons ---------- */
button {
  font: inherit;
  cursor: pointer;
  border-radius: 8px;
  border: 1px solid var(--border);
  padding: 8px 14px;
  background: var(--panel-2);
  color: var(--text);
  transition: filter 0.12s ease, border-color 0.12s ease;
}
button:hover {
  filter: brightness(1.15);
}
button.primary {
  background: var(--accent);
  color: #1a1400;
  border-color: transparent;
  font-weight: 600;
}
button.ghost {
  background: transparent;
}
button.small {
  padding: 4px 10px;
  font-size: 12px;
}
button.paint {
  font-weight: 600;
}
button.paint.green {
  border-color: var(--green);
  color: #9ff0ad;
}
button.paint.red {
  border-color: var(--red);
  color: #ffb3b1;
}

/* ---------- layout ---------- */
.grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 20px;
  padding: 20px 24px;
  max-width: 1240px;
  margin: 0 auto;
}
@media (max-width: 900px) {
  .grid {
    grid-template-columns: 1fr;
  }
}
.panel {
  background: var(--panel);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 18px;
  min-width: 0;
}
.panel-head {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 12px;
  margin-bottom: 6px;
  flex-wrap: wrap;
}
.panel-head h2 {
  font-size: 15px;
  margin: 0;
  color: var(--muted);
  text-transform: uppercase;
  letter-spacing: 0.6px;
}
.paint-controls {
  display: flex;
  gap: 8px;
  flex-wrap: wrap;
}
.hint {
  color: var(--muted);
  font-size: 13px;
  margin: 4px 0 12px;
}

/* ---------- canvas (paintable text) ---------- */
.canvas {
  font-family: var(--mono);
  font-size: 14px;
  white-space: pre-wrap;
  word-break: break-word;
  background: #0b0e13;
  border: 1px solid var(--border);
  border-radius: 8px;
  padding: 14px;
  min-height: 150px;
  max-height: 320px;
  overflow: auto;
  user-select: text;
}
.canvas .match {
  border-bottom: 2px solid var(--match-line);
  background: var(--match);
  border-radius: 2px;
}
.canvas .ex-pos {
  background: var(--green-soft);
  box-shadow: inset 0 0 0 1px var(--green);
  border-radius: 3px;
}
.canvas .ex-neg {
  background: var(--red-soft);
  box-shadow: inset 0 0 0 1px var(--red);
  border-radius: 3px;
  text-decoration: line-through;
  text-decoration-color: var(--red);
}
.canvas .ex-pos.match,
.canvas .ex-neg.match {
  border-bottom: 2px solid var(--match-line);
}

.editor {
  margin-top: 12px;
}
.editor summary {
  cursor: pointer;
  color: var(--muted);
  font-size: 13px;
}
.editor textarea {
  width: 100%;
  margin-top: 8px;
  font-family: var(--mono);
  font-size: 13px;
  background: #0b0e13;
  color: var(--text);
  border: 1px solid var(--border);
  border-radius: 8px;
  padding: 10px;
  resize: vertical;
}

.stats {
  display: flex;
  gap: 18px;
  margin-top: 14px;
  font-size: 13px;
  color: var(--muted);
}
.stat b {
  color: var(--text);
  font-size: 15px;
}

/* ---------- regex row ---------- */
.strategy {
  font-family: var(--mono);
  font-size: 12px;
  color: var(--muted);
}
.strategy.manual {
  color: var(--accent);
}
.regex-row {
  display: flex;
  align-items: center;
  gap: 6px;
  background: #0b0e13;
  border: 1px solid var(--border);
  border-radius: 8px;
  padding: 8px 10px;
  margin-top: 6px;
}
.delim {
  color: var(--muted);
  font-family: var(--mono);
  font-size: 15px;
}
.regex-input {
  flex: 1;
  min-width: 0;
  background: transparent;
  border: none;
  color: var(--accent);
  font-family: var(--mono);
  font-size: 15px;
  outline: none;
}
.regex-meta {
  display: flex;
  align-items: center;
  gap: 14px;
  margin-top: 10px;
  flex-wrap: wrap;
  font-size: 13px;
  color: var(--muted);
}
.chk {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  cursor: pointer;
}

.trust {
  margin-top: 12px;
  font-size: 13px;
  min-height: 18px;
  font-family: var(--mono);
}
.trust.ok {
  color: var(--green);
}
.trust.bad {
  color: var(--red);
}

/* ---------- explanation ---------- */
.panel h3 {
  font-size: 13px;
  text-transform: uppercase;
  letter-spacing: 0.6px;
  color: var(--muted);
  margin: 20px 0 8px;
}
.explain-summary {
  margin: 0 0 10px;
  font-size: 14px;
}
.explain-list {
  list-style: none;
  padding: 0;
  margin: 0;
  display: flex;
  flex-direction: column;
  gap: 4px;
}
.explain-list li {
  display: grid;
  grid-template-columns: minmax(56px, auto) 1fr;
  gap: 12px;
  align-items: baseline;
  padding: 6px 10px;
  background: var(--panel-2);
  border-radius: 6px;
  font-size: 13px;
}
.explain-list code {
  font-family: var(--mono);
  color: var(--accent);
  background: var(--accent-soft);
  padding: 1px 6px;
  border-radius: 4px;
  white-space: pre;
}

/* ---------- export ---------- */
.tabs {
  display: flex;
  gap: 6px;
  align-items: center;
  flex-wrap: wrap;
}
.tab {
  padding: 6px 12px;
  font-size: 13px;
  background: transparent;
}
.tab.active {
  background: var(--accent-soft);
  border-color: var(--accent);
  color: var(--accent);
}
.copy-code {
  margin-left: auto;
}
.export-code {
  font-family: var(--mono);
  font-size: 12.5px;
  background: #0b0e13;
  border: 1px solid var(--border);
  border-radius: 8px;
  padding: 12px;
  margin-top: 8px;
  overflow-x: auto;
  white-space: pre;
  color: #cfe3ff;
}

/* ---------- footer ---------- */
.footer {
  max-width: 1240px;
  margin: 0 auto;
  padding: 8px 24px 40px;
  color: var(--muted);
  font-size: 12.5px;
}

/* ---------- ReDoS warning ---------- */
.redos {
  margin-top: 6px;
  font-size: 12.5px;
  font-family: var(--mono);
  min-height: 0;
}
.redos.danger {
  color: #1a1400;
  background: var(--accent);
  border-radius: 6px;
  padding: 6px 10px;
  font-weight: 600;
}

/* ---------- agent verify-repair trace ---------- */
.agent {
  margin-top: 10px;
}
.agent-repair {
  font-size: 13px;
  color: var(--muted);
  background: var(--panel-2);
  border: 1px solid var(--border);
  border-radius: 8px;
  padding: 8px 10px;
  display: flex;
  align-items: center;
  gap: 8px;
  flex-wrap: wrap;
}
.agent-trace {
  background: var(--panel-2);
  border: 1px solid var(--border);
  border-radius: 8px;
  padding: 8px 10px;
}
.agent-trace > summary {
  cursor: pointer;
  color: var(--muted);
  font-size: 12.5px;
  font-family: var(--mono);
}
.trace-list {
  margin: 10px 0 2px;
  padding-left: 20px;
  display: flex;
  flex-direction: column;
  gap: 8px;
}
.trace-list li {
  font-size: 12.5px;
  display: grid;
  gap: 2px;
}
.trace-list li.trace-ok {
  color: var(--green);
}
.trace-list li.trace-fail {
  color: var(--muted);
}
.trace-act {
  color: var(--text);
}
.trace-list code {
  font-family: var(--mono);
  color: var(--accent);
  background: var(--accent-soft);
  padding: 1px 6px;
  border-radius: 4px;
  white-space: pre-wrap;
  word-break: break-all;
  justify-self: start;
}
.trace-note {
  font-family: var(--mono);
}

/* ---------- dialect compatibility ---------- */
.tab.incompat {
  border-color: var(--red);
  color: #ffb3b1;
  text-decoration: line-through;
}
.dialect-note {
  margin: 8px 0 0;
  font-size: 12.5px;
  font-family: var(--mono);
  min-height: 0;
}
.dialect-note.bad {
  color: var(--red);
}
.dialect-note.info {
  color: var(--muted);
}