:root {
  --page-bg: #0a0a0f;
  --text: #e6e8ef;
  --muted: #9aa0b8;
  --accent: #00f5d4;
  --accent-ink: #04140f;
  --bg-card: #16161f;
  --bg-card-hover: #1c1c28;
  --border-color: rgba(255, 255, 255, 0.08);
  --radius: 12px;
  --shadow: 0 8px 30px rgba(0, 0, 0, 0.35);
  --focus-ring: 0 0 0 3px rgba(0, 245, 212, 0.35);
  --danger: #ff6b6b;
  --color-a: #ff6ec7;
  --color-b: #ffd166;
}

* { box-sizing: border-box; }
html, body { height: 100%; }
body {
  margin: 0;
  font-family: ui-sans-serif, system-ui, -apple-system, Segoe UI, Roboto, "Helvetica Neue", Arial, "Noto Sans", "Apple Color Emoji", "Segoe UI Emoji";
  background: radial-gradient(1200px 600px at 10% -10%, #14141f 0%, #0a0a0f 40%, #0a0a0f 100%);
  color: var(--text);
}

.page-header {
  text-align: center;
  padding: 28px 16px 12px;
}

.page-header h1 {
  margin: 0 0 6px;
  font-size: clamp(20px, 2.6vw, 28px);
  font-weight: 700;
}

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

.page-header__back {
  margin: 8px 0 0;
  font-size: 13px;
}

.page-header__link {
  color: var(--accent);
  text-decoration: none;
  transition: opacity 0.15s ease;
}

.page-header__link:hover {
  opacity: 0.8;
  text-decoration: underline;
}

.container { max-width: 960px; margin: 20px auto 80px; padding: 0 16px; }

mark {
  background: var(--accent);
  color: var(--accent-ink);
  border-radius: 2px;
  padding: 0 1px;
}

/* Commit bar */

.commit-bar {
  max-width: 640px;
  margin: 0 auto 24px;
}

.commit-bar__input {
  width: 100%;
  padding: 14px 16px;
  border: 1px solid var(--border-color);
  border-radius: var(--radius);
  background: var(--bg-card);
  color: var(--text);
  font-size: 15px;
  font-family: inherit;
  box-shadow: var(--shadow);
  outline: none;
  transition: box-shadow 0.15s ease, border-color 0.15s ease;
}

.commit-bar__input::placeholder {
  color: var(--muted);
}

.commit-bar__input:focus {
  border-color: var(--accent);
  box-shadow: var(--focus-ring);
}

.commit-bar__path {
  margin: 8px 4px 0;
  color: var(--muted);
  font-size: 12px;
}

/* Graph */

.graph {
  max-width: 960px;
  margin: 0 auto 32px;
}

.graph__toolbar {
  display: flex;
  align-items: center;
  flex-wrap: wrap;
  justify-content: flex-end;
  gap: 8px;
  margin-bottom: 8px;
}

.graph__tool {
  padding: 6px 14px;
  border: 1px solid var(--border-color);
  border-radius: 999px;
  background: transparent;
  color: var(--muted);
  font-size: 12px;
  font-family: inherit;
  cursor: pointer;
  transition: background 0.15s ease, color 0.15s ease, border-color 0.15s ease;
}

.graph__tool:hover {
  background: rgba(255, 255, 255, 0.06);
  color: var(--text);
  border-color: rgba(255, 255, 255, 0.16);
}

.graph__tool:focus-visible {
  outline: none;
  box-shadow: var(--focus-ring);
}

.graph__tool--active {
  background: rgba(0, 245, 212, 0.16);
  border-color: var(--accent);
  color: var(--accent);
}

.graph__tool:disabled {
  opacity: 0.4;
  cursor: default;
}

.graph__compare-info {
  font-size: 12px;
  color: var(--muted);
}

.graph__compare-chip {
  display: inline-block;
  margin-right: 6px;
  padding: 2px 8px;
  border-radius: 999px;
  font-size: 11px;
  font-weight: 700;
}

.graph__compare-chip--a {
  border: 1px solid rgba(255, 110, 199, 0.35);
  background: rgba(255, 110, 199, 0.14);
  color: var(--color-a);
}

.graph__compare-chip--b {
  border: 1px solid rgba(255, 209, 102, 0.35);
  background: rgba(255, 209, 102, 0.14);
  color: var(--color-b);
}

.graph__pane {
  position: relative;
  height: 280px;
  overflow: auto;
  border: 1px solid var(--border-color);
  border-radius: var(--radius);
  background-color: #0d0d14;
  background-image:
    linear-gradient(rgba(255, 255, 255, 0.04) 1px, transparent 1px),
    linear-gradient(90deg, rgba(255, 255, 255, 0.04) 1px, transparent 1px);
  background-size: 24px 24px;
}

.graph__edges,
.graph__nodes {
  position: absolute;
  top: 0;
  left: 0;
}

.graph__edges path {
  stroke: rgba(0, 245, 212, 0.35);
  stroke-width: 2;
  fill: none;
}

.graph__node {
  position: absolute;
  display: flex;
  flex-direction: column;
  align-items: flex-start;
  justify-content: center;
  gap: 4px;
  padding: 8px 12px;
  border: 1px solid var(--border-color);
  border-radius: 10px;
  background: var(--bg-card);
  color: var(--text);
  font-family: inherit;
  text-align: left;
  cursor: pointer;
  transition: transform 0.15s ease, background 0.15s ease, box-shadow 0.15s ease;
}

.graph__node:hover {
  transform: translateY(-2px);
  background: var(--bg-card-hover);
  box-shadow: var(--shadow);
  z-index: 2;
}

.graph__node:focus-visible {
  outline: none;
  box-shadow: var(--focus-ring);
  z-index: 2;
}

.graph__node::after {
  content: attr(data-tooltip);
  position: absolute;
  top: calc(100% + 8px);
  left: 0;
  width: max-content;
  max-width: 320px;
  white-space: normal;
  padding: 6px 10px;
  border: 1px solid var(--border-color);
  border-radius: 8px;
  background: var(--bg-card);
  color: var(--text);
  font-size: 12px;
  font-weight: 400;
  line-height: 1.4;
  box-shadow: var(--shadow);
  pointer-events: none;
  opacity: 0;
  transition: opacity 0.15s ease 0.12s;
  z-index: 3;
}

.graph__node:hover::after,
.graph__node:focus-visible::after {
  opacity: 1;
}

.graph__node-label {
  display: block;
  width: 100%;
  overflow: hidden;
  white-space: nowrap;
  text-overflow: ellipsis;
  font-size: 13px;
  font-weight: 600;
}

.graph__node-badge {
  font-size: 11px;
  color: var(--accent);
}

.graph__node--current {
  border-color: var(--accent);
  box-shadow: 0 0 0 2px var(--accent);
}

.graph__node--empty {
  opacity: 0.45;
}

.graph__node--empty .graph__node-badge {
  color: var(--danger);
}

.graph__node--a {
  border-color: var(--color-a);
  box-shadow: 0 0 0 2px var(--color-a);
}

.graph__node--b {
  border-color: var(--color-b);
  box-shadow: 0 0 0 2px var(--color-b);
}

.graph__node--a:hover {
  box-shadow: 0 0 0 2px var(--color-a);
}

.graph__node--a:focus-visible {
  box-shadow: 0 0 0 2px var(--color-a), var(--focus-ring);
}

.graph__node--b:hover {
  box-shadow: 0 0 0 2px var(--color-b);
}

.graph__node--b:focus-visible {
  box-shadow: 0 0 0 2px var(--color-b), var(--focus-ring);
}

.graph__node--current:hover,
.graph__node--current:focus-visible {
  box-shadow: 0 0 0 2px var(--accent);
}

/* Results */

.results__status {
  margin: 0 0 16px;
  color: var(--muted);
  font-size: 14px;
  text-align: center;
}

.results__grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(240px, 1fr));
  gap: 16px;
}

.results__card {
  padding: 18px;
  border-radius: var(--radius);
  border: 1px solid var(--border-color);
  background: var(--bg-card);
  transition: transform 0.15s ease, box-shadow 0.15s ease, background 0.15s ease;
}

.results__card:hover {
  transform: translateY(-3px);
  background: var(--bg-card-hover);
  box-shadow: var(--shadow);
}

.results__card-title {
  margin: 0 0 8px;
  font-size: 16px;
  font-weight: 700;
}

.results__card-category {
  display: inline-block;
  margin-bottom: 10px;
  padding: 3px 8px;
  border-radius: 999px;
  border: 1px solid rgba(0, 245, 212, 0.24);
  background: rgba(0, 245, 212, 0.08);
  color: var(--accent);
  font-size: 11px;
  font-weight: 700;
  letter-spacing: 0.02em;
  text-transform: uppercase;
}

.results__card-desc {
  margin: 0;
  color: var(--muted);
  font-size: 13px;
  line-height: 1.6;
}

.results__empty {
  margin: 40px 0;
  color: var(--muted);
  font-size: 14px;
  text-align: center;
}

.results__group {
  margin-top: 24px;
  padding-left: 14px;
  border-left: 3px solid var(--accent);
}

.results__group--a {
  border-left-color: var(--color-a);
}

.results__group--b {
  border-left-color: var(--color-b);
}

.results__group-title {
  margin: 0 0 12px;
  font-size: 14px;
  font-weight: 700;
  color: var(--accent);
}

.results__group--a .results__group-title {
  color: var(--color-a);
}

.results__group--b .results__group-title {
  color: var(--color-b);
}

.results__group-none {
  margin: 0 0 12px;
  color: var(--muted);
  font-size: 13px;
}

/* ─────────────────────────────────────────────────────────
   Mobile-first responsive enhancements
   ───────────────────────────────────────────────────────── */

@media (max-width: 768px) {
  .page-header {
    padding: 20px 16px 10px;
  }

  .page-header h1 {
    font-size: 22px;
  }

  .page-header__subtitle {
    font-size: 13px;
    line-height: 1.5;
  }

  .container {
    margin: 16px auto 40px;
    padding: 0 12px;
  }
}

@media (max-width: 480px) {
  .container {
    padding: 0 10px;
  }

  .graph__pane {
    overflow-x: auto;
  }

  .results__grid {
    grid-template-columns: 1fr;
    gap: 12px;
  }

  .results__card {
    padding: 14px;
  }
}