:root {
  color-scheme: light;
  --bg: #f3efe6;
  --fg: #201b16;
  --muted: #74695d;
  --panel-bg: rgba(255, 252, 245, 0.78);
  --panel-strong: #fffaf0;
  --border: rgba(48, 36, 24, 0.14);
  --accent: #9b3f22;
  --accent-soft: #ead2c5;
  --shadow: 0 24px 70px rgba(80, 49, 22, 0.14);
  --error-bg: #f8ddd6;
  --error-fg: #8c260f;
}

@media (prefers-color-scheme: dark) {
  :root {
    color-scheme: dark;
    --bg: #181510;
    --fg: #f5efe4;
    --muted: #b7aa99;
    --panel-bg: rgba(35, 30, 23, 0.82);
    --panel-strong: #242017;
    --border: rgba(245, 239, 228, 0.14);
    --accent: #d87845;
    --accent-soft: #3b2a20;
    --shadow: 0 24px 70px rgba(0, 0, 0, 0.35);
    --error-bg: #3a1b16;
    --error-fg: #ffb39e;
  }
}

* { box-sizing: border-box; }

html { scroll-behavior: smooth; }

body {
  margin: 0;
  font-family: Outfit, system-ui, sans-serif;
  background:
    radial-gradient(circle at 18% 0%, rgba(155, 63, 34, 0.18), transparent 34rem),
    radial-gradient(circle at 88% 8%, rgba(31, 74, 88, 0.12), transparent 26rem),
    var(--bg);
  color: var(--fg);
  line-height: 1.5;
}

body::before {
  content: "";
  position: fixed;
  inset: 0;
  pointer-events: none;
  opacity: 0.32;
  background-image: url("data:image/svg+xml,%3Csvg viewBox='0 0 160 160' xmlns='http://www.w3.org/2000/svg'%3E%3Cfilter id='n'%3E%3CfeTurbulence type='fractalNoise' baseFrequency='.8' numOctaves='3' stitchTiles='stitch'/%3E%3C/filter%3E%3Crect width='100%25' height='100%25' filter='url(%23n)' opacity='.22'/%3E%3C/svg%3E");
  mix-blend-mode: multiply;
}

.skip-link {
  position: absolute;
  left: 1rem;
  top: -4rem;
  z-index: 2;
  padding: 0.6rem 0.8rem;
  background: var(--fg);
  color: var(--bg);
  border-radius: 0.7rem;
}

.skip-link:focus { top: 1rem; }

a { color: var(--accent); text-underline-offset: 0.18em; }

.kt-text,
.kt-text-output,
.output { font-family: "Noto Sans Khmer", "Khmer OS", system-ui, sans-serif; }

.site-header {
  max-width: 1180px;
  margin: 0 auto;
  padding: 1.2rem 1.25rem 1rem;
}

.eyebrow {
  margin: 0 0 0.8rem;
  color: var(--accent);
  font-size: 0.78rem;
  font-weight: 700;
  letter-spacing: 0.16em;
  text-transform: uppercase;
}

.site-header h1 {
  max-width: 720px;
  margin: 0;
  font-size: clamp(2rem, 4vw, 4rem);
  line-height: 0.95;
  letter-spacing: -0.055em;
  text-wrap: balance;
}

.tagline {
  max-width: 680px;
  margin: 0.55rem 0 0.75rem;
  color: var(--muted);
  font-size: 1rem;
  text-wrap: pretty;
}

.status {
  display: inline-flex;
  align-items: center;
  min-height: 2.2rem;
  padding: 0.45rem 0.85rem;
  border: 1px solid var(--border);
  border-radius: 0.85rem;
  background: var(--panel-bg);
  box-shadow: 0 8px 30px rgba(80, 49, 22, 0.08);
  font-size: 0.9rem;
  font-weight: 700;
}

.status-loading { color: #8a6100; }
.status-ready { color: #17603d; }
.status-error { background: var(--error-bg); color: var(--error-fg); }

.layout {
  display: grid;
  grid-template-columns: 180px minmax(0, 1fr) 330px;
  gap: 1rem;
  max-width: 1180px;
  margin: 0 auto;
  padding: 0 1.25rem 3rem;
  align-items: start;
}

.sidebar,
.code-panel { position: sticky; top: 1rem; }

.tool-list {
  list-style: none;
  margin: 0;
  padding: 0.45rem;
  display: flex;
  flex-direction: column;
  gap: 0.35rem;
  border: 1px solid var(--border);
  border-radius: 1.2rem;
  background: var(--panel-bg);
  box-shadow: var(--shadow);
  backdrop-filter: blur(18px);
}

.tool-item {
  width: 100%;
  padding: 0.75rem 0.85rem;
  border: 0;
  border-radius: 0.85rem;
  background: transparent;
  color: var(--muted);
  cursor: pointer;
  font: inherit;
  font-size: 0.95rem;
  font-weight: 700;
  text-align: left;
  transition: transform 180ms ease, background 180ms ease, color 180ms ease;
}

.tool-item:hover { transform: translateY(-1px); color: var(--fg); }
.tool-item:active { transform: translateY(1px) scale(0.99); }
.tool-item:focus-visible,
.copy-btn:focus-visible,
.run-btn:focus-visible,
textarea:focus-visible,
select:focus-visible,
input:focus-visible { outline: 3px solid var(--accent-soft); outline-offset: 2px; }

.tool-item.active { background: var(--fg); color: var(--bg); }

.workspace { min-width: 0; }
.workspace.pyodide-loading .output-section,
.workspace.pyodide-loading .diagram-section { opacity: 0.5; pointer-events: none; }

.tool-panel {
  display: none;
  border: 1px solid var(--border);
  border-radius: 1.6rem;
  padding: clamp(1rem, 3vw, 2rem);
  background: var(--panel-bg);
  box-shadow: var(--shadow);
  backdrop-filter: blur(18px);
}

.tool-panel.active { display: block; }

.tool-panel h2 {
  margin: 0;
  font-size: clamp(2rem, 4vw, 3.4rem);
  line-height: 0.95;
  letter-spacing: -0.05em;
}

.desc {
  max-width: 58ch;
  color: var(--muted);
  margin: 0.7rem 0 1.2rem;
  font-size: 1.04rem;
  text-wrap: pretty;
}

.input-label {
  display: block;
  margin-bottom: 0.45rem;
  color: var(--accent);
  font-size: 0.78rem;
  font-weight: 800;
  letter-spacing: 0.12em;
  text-transform: uppercase;
}

textarea.kt-text {
  width: 100%;
  min-height: 9rem;
  padding: 1rem;
  border: 1px solid var(--border);
  border-radius: 1rem;
  background: var(--panel-strong);
  color: var(--fg);
  box-shadow: inset 0 1px 0 rgba(255,255,255,0.35);
  font-size: 1.2rem;
  line-height: 1.8;
  resize: vertical;
}

.run-btn {
  margin-top: 0.8rem;
  padding: 0.75rem 1rem;
  border: 0;
  border-radius: 0.9rem;
  background: var(--accent);
  color: #fffaf0;
  cursor: pointer;
  font: inherit;
  font-weight: 800;
  transition: transform 180ms ease, filter 180ms ease;
}

.run-btn:hover { transform: translateY(-1px); filter: brightness(1.05); }
.run-btn:active { transform: translateY(1px) scale(0.98); }

.error {
  margin-top: 0.9rem;
  padding: 0.8rem 0.95rem;
  border-radius: 0.9rem;
  background: var(--error-bg);
  color: var(--error-fg);
}

.output-header,
.code-block-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 1rem;
  margin-bottom: 0.55rem;
}

.output-header h3,
.diagram-section h3 {
  margin: 0;
  color: var(--muted);
  font-size: 0.82rem;
  font-weight: 800;
  letter-spacing: 0.12em;
  text-transform: uppercase;
}

.output-section { margin-top: 1.35rem; }
.diagram-section { margin-top: 1.6rem; }

.copy-btn {
  padding: 0.4rem 0.7rem;
  border: 1px solid var(--border);
  border-radius: 0.7rem;
  background: var(--panel-strong);
  color: var(--fg);
  cursor: pointer;
  font: inherit;
  font-size: 0.78rem;
  font-weight: 800;
  transition: transform 180ms ease, background 180ms ease;
}

.copy-btn:hover { transform: translateY(-1px); background: var(--accent-soft); }
.copy-btn:active { transform: translateY(1px) scale(0.98); }
.copy-btn.copied { background: #17603d; color: #fff; border-color: #17603d; }

.output ul {
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem;
  margin: 0;
  padding: 0;
  list-style: none;
}

.output li,
.kt-text-output {
  background: var(--panel-strong);
  border: 1px solid var(--border);
  border-radius: 0.85rem;
}

.output li { padding: 0.45rem 0.7rem; }

.kt-text-output {
  white-space: pre-wrap;
  word-break: break-word;
  margin: 0;
  padding: 1rem;
  font-size: 1.1rem;
  line-height: 1.8;
}

.before-after { display: grid; grid-template-columns: 1fr 1fr; gap: 1rem; }
.before-after h4 { margin: 0 0 0.3rem; color: var(--muted); }

table {
  width: 100%;
  border-collapse: separate;
  border-spacing: 0;
  overflow: hidden;
  border: 1px solid var(--border);
  border-radius: 1rem;
  background: var(--panel-strong);
  font-variant-numeric: tabular-nums;
}

table th,
table td { padding: 0.65rem 0.75rem; text-align: left; border-bottom: 1px solid var(--border); }
table tr:last-child td { border-bottom: 0; }
table th { color: var(--muted); font-family: Outfit, system-ui, sans-serif; }

.diagram-flow { display: flex; flex-wrap: wrap; align-items: center; gap: 0.5rem; }
.diagram-stage {
  border: 1px solid var(--border);
  border-radius: 0.85rem;
  background: var(--panel-strong);
  padding: 0.65rem 0.8rem;
  font-size: 0.84rem;
  font-weight: 700;
  text-align: center;
}
.diagram-arrow { color: var(--accent); font-size: 1.2rem; flex: 0 0 auto; }
.diagram-fork { display: flex; flex-direction: column; gap: 0.4rem; }
.diagram-branch { display: flex; align-items: center; gap: 0.5rem; }
.diagram-badge { display: block; margin-top: 0.25rem; font-size: 0.75rem; font-weight: 800; color: var(--accent); }
.diagram-grid { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 0.4rem; margin-top: 0.5rem; text-align: left; }
.diagram-grid-cell { border: 1px solid var(--border); border-radius: 0.65rem; padding: 0.35rem 0.5rem; font-size: 0.75rem; display: flex; justify-content: space-between; gap: 0.5rem; background: var(--panel-bg); }
.diagram-grid-label { color: var(--muted); }
.diagram-grid-value { font-weight: 800; }

.code-panel { display: flex; flex-direction: column; gap: 1rem; }
.code-block-wrap {
  border: 1px solid var(--border);
  border-radius: 1.2rem;
  overflow: hidden;
  background: var(--panel-bg);
  box-shadow: var(--shadow);
  backdrop-filter: blur(18px);
}
.code-block-header { padding: 0.55rem 0.75rem; border-bottom: 1px solid var(--border); margin-bottom: 0; color: var(--muted); font-size: 0.78rem; font-weight: 800; letter-spacing: 0.12em; text-transform: uppercase; }
.code-block { margin: 0; padding: 0.85rem; background: var(--panel-strong); font-family: ui-monospace, SFMono-Regular, Menlo, Consolas, monospace; font-size: 0.78rem; white-space: pre-wrap; word-break: break-word; overflow-x: auto; }

.site-footer {
  max-width: 1180px;
  margin: 0 auto;
  padding: 0 1.25rem 3rem;
  color: var(--muted);
  font-size: 0.92rem;
}

.site-footer p { margin: 0.35rem 0; }

@media (max-width: 1000px) {
  .layout { grid-template-columns: 1fr; }
  .sidebar,
  .code-panel { position: static; }
  .tool-list { flex-direction: row; flex-wrap: wrap; }
  .tool-item { width: auto; }
}

@media (max-width: 600px) {
  .site-header { padding-top: 1rem; }
  .before-after,
  .diagram-grid { grid-template-columns: 1fr; }
  .tool-list { border-radius: 1rem; }
  .tool-panel { border-radius: 1.2rem; }
}