/* Git Commit Tree — dark, git-flavored theme */
:root {
  --bg: #0d1117;
  --bg-panel: #161b22;
  --bg-inset: #0d1117;
  --border: #30363d;
  --text: #e6edf3;
  --text-dim: #8b949e;
  --accent: #3fb950;
  --blue: #58a6ff;
  --red: #f85149;
  --amber: #d29922;
  --mono: ui-monospace, SFMono-Regular, "SF Mono", Menlo, Consolas, "Liberation Mono", monospace;
  --sans: -apple-system, BlinkMacSystemFont, "Segoe UI", "Noto Sans", Helvetica, Arial, sans-serif;
}

* { box-sizing: border-box; }
html, body { margin: 0; padding: 0; }
body {
  background: var(--bg);
  color: var(--text);
  font-family: var(--sans);
  min-height: 100vh;
  display: flex;
  flex-direction: column;
}

/* ---------- header ---------- */
.site-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  padding: 14px 20px 10px;
  border-bottom: 1px solid var(--border);
  flex-wrap: wrap;
}
.title-block h1 {
  margin: 0;
  font-size: 20px;
  display: flex;
  align-items: center;
  gap: 8px;
  letter-spacing: 0.2px;
}
.logo { display: inline-flex; }
.tagline { margin: 2px 0 0; color: var(--text-dim); font-size: 13px; }
.header-controls { display: flex; gap: 8px; }

.ctl-btn {
  font: 600 13px var(--sans);
  color: var(--text);
  background: #21262d;
  border: 1px solid var(--border);
  border-radius: 8px;
  padding: 7px 14px;
  cursor: pointer;
  min-height: 36px;
  transition: background 0.15s, border-color 0.15s;
}
.ctl-btn:hover:not(:disabled) { background: #30363d; border-color: #8b949e; }
.ctl-btn:disabled { opacity: 0.45; cursor: not-allowed; }
.ctl-btn.danger { color: #ffa198; }
.ctl-btn.danger[data-armed] { background: #b62324; color: #fff; border-color: #f85149; }
.ctl-btn.small { padding: 4px 10px; min-height: 30px; font-size: 12px; }

/* ---------- walkthroughs ---------- */
.examples-bar {
  display: flex;
  align-items: flex-start;
  gap: 12px;
  padding: 10px 20px;
  border-bottom: 1px solid var(--border);
  background: #0d1117;
  flex-wrap: wrap;
}
.examples-label { font-size: 12px; color: var(--text-dim); padding-top: 9px; white-space: nowrap; }
.examples-row { display: flex; gap: 8px; flex-wrap: wrap; flex: 1; }
.example-btn {
  display: flex;
  flex-direction: column;
  align-items: flex-start;
  gap: 1px;
  background: var(--bg-panel);
  border: 1px solid var(--border);
  border-radius: 8px;
  color: var(--text);
  padding: 7px 12px;
  cursor: pointer;
  text-align: left;
  min-height: 44px;
  transition: border-color 0.15s, background 0.15s;
}
.example-btn strong { font-size: 12.5px; }
.example-btn span { font-size: 11px; color: var(--text-dim); max-width: 260px; }
.example-btn:hover:not(:disabled) { border-color: var(--accent); background: #1a2230; }
.example-btn.running { border-color: var(--amber); background: #2a2410; }
.example-btn:disabled:not(.running) { opacity: 0.45; cursor: not-allowed; }

/* ---------- main layout ---------- */
.layout {
  display: grid;
  grid-template-columns: minmax(0, 1fr) minmax(360px, 42%);
  gap: 0;
  flex: 1;
  min-height: 0;
}
.graph-panel {
  display: flex;
  flex-direction: column;
  border-right: 1px solid var(--border);
  min-height: 420px;
}
.side-panel {
  display: flex;
  flex-direction: column;
  min-height: 0;
}
.terminal-panel {
  display: flex;
  flex-direction: column;
  flex: 1.2;
  min-height: 260px;
  border-bottom: 1px solid var(--border);
}
.inspector-panel {
  display: flex;
  flex-direction: column;
  flex: 1;
  min-height: 220px;
}
.panel-head {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 8px 14px;
  border-bottom: 1px solid var(--border);
  background: var(--bg-panel);
}
.panel-head h2 {
  margin: 0;
  font-size: 12px;
  text-transform: uppercase;
  letter-spacing: 0.12em;
  color: var(--text-dim);
  font-weight: 700;
}
.panel-hint { font-size: 11px; color: var(--text-dim); }
.graph-tools { display: flex; gap: 6px; align-items: center; }

/* ---------- graph ---------- */
.branch-chips {
  display: flex;
  gap: 6px;
  flex-wrap: wrap;
  padding: 8px 14px;
  border-bottom: 1px solid var(--border);
  background: var(--bg-panel);
  min-height: 44px;
  align-items: center;
}
.branch-chip {
  font: 600 12px var(--mono);
  color: var(--blue);
  background: #0d1b2e;
  border: 1px solid #1f3a5f;
  border-radius: 999px;
  padding: 5px 12px;
  cursor: pointer;
  min-height: 30px;
}
.branch-chip:hover { border-color: var(--blue); }
.branch-chip.current { color: #0d1117; background: var(--accent); border-color: var(--accent); }
.branch-chip .chip-hash { opacity: 0.7; font-weight: 400; }
.detached-chip { color: var(--amber); background: #2a2410; border: 1px solid #9e6a03; cursor: default; }

.graph-scroll {
  flex: 1;
  overflow: auto;
  position: relative;
  background:
    radial-gradient(circle at 1px 1px, #21262d 1px, transparent 0) 0 0 / 26px 26px,
    var(--bg-inset);
  min-height: 320px;
}
.graph-wrap { transition: transform 0.2s ease; }
.graph-empty { color: var(--text-dim); padding: 20px; font-family: var(--mono); font-size: 13px; }

#graph-svg { display: block; }

/* edges */
.edge {
  stroke-width: 2.5;
  opacity: 0.9;
  transition: opacity 0.4s, d 0.5s ease;
}
.edge.merge-edge { stroke-dasharray: 0; }
.edge.leaving { opacity: 0; }

/* nodes */
.node {
  cursor: pointer;
  transition: transform 0.55s cubic-bezier(0.22, 1, 0.36, 1), opacity 0.4s;
  outline: none;
}
.node .node-ring { fill: none; stroke-width: 2; opacity: 0.85; }
.node .node-halo { fill: transparent; transition: fill 0.15s; }
.node:hover .node-halo, .node:focus-visible .node-halo { fill: rgba(88, 166, 255, 0.12); }
.node.merge .node-ring { stroke-width: 3.5; }
.node.selected .node-halo { fill: rgba(88, 166, 255, 0.22); }
.node.selected .node-ring { stroke-width: 4; }
.node-hash {
  font: 11px var(--mono);
  fill: var(--text-dim);
  user-select: none;
}
.node.entering { animation: node-pop 0.5s cubic-bezier(0.34, 1.56, 0.64, 1); }
.node.leaving { opacity: 0; }
@keyframes node-pop {
  0% { opacity: 0; scale: 0.3; }
  60% { opacity: 1; scale: 1.25; }
  100% { scale: 1; }
}

/* branch labels */
.branch-label {
  transition: transform 0.55s cubic-bezier(0.22, 1, 0.36, 1);
  pointer-events: none;
}
.branch-label text {
  font: 600 11.5px var(--mono);
  fill: #0d1117;
}
.branch-label rect { opacity: 0.95; }
.branch-label.head rect { stroke: #fff; stroke-width: 1.4; }
.branch-label.detached rect { stroke: var(--amber); }
.branch-label.detached text { fill: #ffd68a; }
.branch-label.entering { animation: label-in 0.45s ease; }
@keyframes label-in {
  from { opacity: 0; }
  to { opacity: 1; }
}

/* ---------- terminal ---------- */
.terminal {
  flex: 1;
  display: flex;
  flex-direction: column;
  min-height: 0;
  background: #010409;
}
.term-scroll {
  flex: 1;
  overflow-y: auto;
  padding: 10px 14px;
  font: 13px/1.55 var(--mono);
}
.term-line { white-space: pre-wrap; word-break: break-word; }
.term-echo { color: #fff; margin-top: 8px; }
.term-prompt-inline { color: var(--accent); font-weight: 700; }
.term-out { color: #c9d1d9; }
.term-success { color: var(--accent); }
.term-error { color: var(--red); }
.term-info { color: var(--amber); }
.term-muted { color: var(--text-dim); }

.term-input-row {
  display: flex;
  align-items: center;
  gap: 8px;
  border-top: 1px solid var(--border);
  padding: 8px 12px;
  background: var(--bg-panel);
}
.term-prompt { font: 700 13px var(--mono); color: var(--accent); white-space: nowrap; }
.term-prompt.detached { color: var(--amber); }
.term-input {
  flex: 1;
  background: transparent;
  border: none;
  outline: none;
  color: #fff;
  font: 13px var(--mono);
  caret-color: var(--accent);
  min-height: 30px;
}
.term-input::placeholder { color: #484f58; }
.term-clear {
  font: 11px var(--mono);
  color: var(--text-dim);
  background: transparent;
  border: 1px solid var(--border);
  border-radius: 6px;
  padding: 5px 10px;
  cursor: pointer;
  min-height: 30px;
}
.term-clear:hover { color: var(--text); border-color: var(--text-dim); }

.hash-chip {
  font: 11px var(--mono);
  color: var(--blue);
  background: #0d1b2e;
  border: 1px solid #1f3a5f;
  border-radius: 5px;
  padding: 1px 5px;
  cursor: pointer;
  margin: 0 1px;
}
.hash-chip:hover { border-color: var(--blue); }
.hash-chip.copied { border-color: var(--accent); color: var(--accent); }

/* ---------- inspector ---------- */
.inspector-body {
  display: flex;
  min-height: 0;
  flex: 1;
}
.log-list {
  list-style: none;
  margin: 0;
  padding: 6px;
  flex: 1.1;
  overflow-y: auto;
  display: flex;
  flex-direction: column;
  gap: 2px;
  border-right: 1px solid var(--border);
}
.log-item {
  display: grid;
  grid-template-columns: auto 1fr;
  grid-template-areas: "hash msg" "hash refs";
  column-gap: 8px;
  align-items: center;
  background: transparent;
  border: 1px solid transparent;
  border-radius: 6px;
  padding: 5px 8px;
  cursor: pointer;
  text-align: left;
  color: var(--text);
  min-height: 40px;
}
.log-item:hover { background: #1c2128; }
.log-item.selected { background: #1f2a3a; border-color: var(--blue); }
.log-hash { grid-area: hash; font: 11.5px var(--mono); color: var(--blue); align-self: start; padding-top: 2px; }
.log-msg { grid-area: msg; font-size: 12.5px; overflow: hidden; text-overflow: ellipsis; white-space: nowrap; }
.log-refs { grid-area: refs; display: flex; gap: 4px; flex-wrap: wrap; }
.ref-badge {
  font: 600 10px var(--mono);
  background: #21262d;
  border: 1px solid var(--border);
  border-radius: 999px;
  padding: 1px 7px;
  color: var(--text-dim);
}
.ref-badge.head { background: var(--accent); border-color: var(--accent); color: #0d1117; }
.merge-badge { background: #2a1f3d; border-color: #6e40c9; color: #d2a8ff; }

.detail {
  flex: 1;
  overflow-y: auto;
  padding: 10px 12px;
  min-width: 0;
}
.detail-empty { color: var(--text-dim); font-size: 12.5px; line-height: 1.7; }
.detail-empty code { font-family: var(--mono); color: var(--accent); }
.detail-card { display: flex; flex-direction: column; gap: 9px; font-size: 12.5px; }
.detail-row { display: flex; gap: 8px; align-items: baseline; flex-wrap: wrap; }
.detail-k {
  flex: 0 0 64px;
  color: var(--text-dim);
  font-size: 10.5px;
  text-transform: uppercase;
  letter-spacing: 0.08em;
}
.detail-msg { font-weight: 600; }
.detail-v { color: var(--text-dim); }
.detail .hash-chip { word-break: break-all; text-align: left; }

/* ---------- footer ---------- */
.site-footer {
  border-top: 1px solid var(--border);
  padding: 10px 20px;
  color: var(--text-dim);
  font-size: 12px;
}
.site-footer p { margin: 0; }

/* ---------- responsive ---------- */
@media (max-width: 900px) {
  .layout { grid-template-columns: 1fr; }
  .graph-panel { border-right: none; border-bottom: 1px solid var(--border); min-height: 300px; }
  .graph-scroll { min-height: 260px; max-height: 52vh; }
  .side-panel { min-height: 60vh; }
  .terminal-panel { min-height: 240px; }
  .inspector-body { flex-direction: column; }
  .log-list { border-right: none; border-bottom: 1px solid var(--border); max-height: 180px; }
  .site-header { padding: 12px 14px 8px; }
  .examples-bar { padding: 8px 14px; }
  .example-btn span { display: none; }
  .tagline { font-size: 12px; }
}
@media (max-width: 480px) {
  .title-block h1 { font-size: 17px; }
  .examples-label { width: 100%; padding-top: 0; }
  .panel-hint { display: none; }
}

/* ---------- reduced motion ---------- */
@media (prefers-reduced-motion: reduce) {
  .node, .branch-label, .edge, .graph-wrap { transition: none !important; }
  .node.entering, .branch-label.entering { animation: none !important; }
}