:root {
  color-scheme: light;
  --page: #f9f9f7;
  --surface: #ffffff;
  --text-primary: #0b0b0b;
  --text-secondary: #52514e;
  --text-muted: #898781;
  --hairline: #e1e0d9;
  --border: rgba(11, 11, 11, 0.10);
  --accent: #2a78d6;
  --accent-ink: #ffffff;
  --error: #d03b3b;
  --font: system-ui, -apple-system, "Segoe UI", Roboto, sans-serif;
}
@media (prefers-color-scheme: dark) {
  :root {
    color-scheme: dark;
    --page: #0d0d0d;
    --surface: #1a1a19;
    --text-primary: #ffffff;
    --text-secondary: #c3c2b7;
    --text-muted: #898781;
    --hairline: #2c2c2a;
    --border: rgba(255, 255, 255, 0.10);
    --accent: #3987e5;
    --error: #e66767;
  }
}

* { box-sizing: border-box; }
body {
  margin: 0;
  background: var(--page);
  color: var(--text-primary);
  font: 15px/1.45 var(--font);
}
code { font-size: 0.92em; }
h1 { margin: 0; font-size: 2.4rem; line-height: 1.1; }
h2 { margin: 0 0 0.6rem; font-size: 1.05rem; }

.top {
  display: flex;
  flex-wrap: wrap;
  justify-content: space-between;
  align-items: flex-start; /* opening the how-to panel never moves the title */
  gap: 0.5rem 2rem;
  padding: 1.5rem 2rem 1rem;
  max-width: 1500px;
  margin: 0 auto;
}
.lede { margin: 0.25rem 0 0; color: var(--text-secondary); }

main { max-width: 1500px; margin: 0 auto; padding: 0 2rem 2rem; }

.card {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 10px;
  padding: 1rem 1.25rem;
}

.drop {
  border: 2px dashed var(--hairline);
  border-radius: 12px;
  background: var(--surface);
  padding: 2rem;
  text-align: center;
  cursor: pointer;
  transition: border-color 0.15s, background 0.15s;
}
.drop:hover, .drop:focus-visible, .drop.over { border-color: var(--accent); outline: none; }
.drop.compact { padding: 0.9rem; }
.drop.compact .drop-sub { display: none; }
.drop-title { margin: 0; font-size: 1.15rem; font-weight: 600; }
.drop-sub { margin: 0.4rem 0 0; color: var(--text-secondary); }
.status { margin: 0.5rem 0 0; color: var(--text-secondary); min-height: 1.2em; }
.status.error { color: var(--error); }

button.link {
  background: none;
  border: 0;
  padding: 0;
  font: inherit;
  color: var(--accent);
  cursor: pointer;
  text-decoration: underline;
}
button.primary {
  margin-top: 0.6rem;
  width: 100%;
  padding: 0.6rem 1rem;
  border: 0;
  border-radius: 8px;
  background: var(--accent);
  color: var(--accent-ink);
  font: 600 1rem var(--font);
  cursor: pointer;
}
button.primary:disabled { opacity: 0.5; cursor: default; }

#pick { margin-top: 1rem; display: flex; gap: 0.75rem; align-items: center; flex-wrap: wrap; }
#pick[hidden] { display: none; }

.workspace {
  display: grid;
  grid-template-columns: 330px minmax(0, 1fr);
  gap: 1.25rem;
  margin-top: 1.25rem;
  align-items: start;
}
.workspace[hidden] { display: none; }
@media (max-width: 900px) { .workspace { grid-template-columns: 1fr; } }

.options { display: flex; flex-direction: column; gap: 1rem; position: sticky; top: 1rem; }
fieldset {
  margin: 0;
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 10px;
  padding: 0.75rem 1rem 1rem;
}
legend { font-weight: 600; padding: 0 0.25rem; }
.hint { margin: 0.25rem 0 0.5rem; color: var(--text-muted); font-size: 0.85rem; }
label.row {
  display: grid;
  grid-template-columns: 105px minmax(0, 1fr);
  align-items: center;
  gap: 0.5rem;
  margin: 0.45rem 0;
}
.row.pair { display: flex; gap: 0.75rem; margin: 0.45rem 0; }
.row.pair label { display: flex; align-items: center; gap: 0.3rem; white-space: nowrap; }
.row.pair input { width: 5.5rem; }
label.check { display: flex; align-items: center; gap: 0.45rem; margin: 0.35rem 0; }
select, input[type="text"], input[type="number"] {
  font: inherit;
  color: inherit;
  background: var(--page);
  border: 1px solid var(--border);
  border-radius: 6px;
  padding: 0.3rem 0.45rem;
  min-width: 0;
}

.curve-list { max-height: 330px; overflow-y: auto; margin: 0 -0.25rem; padding: 0 0.25rem; }
.curve-list label { display: flex; align-items: center; gap: 0.45rem; margin: 0.2rem 0; }
.swatch { width: 18px; height: 3px; border-radius: 2px; flex: none; }
.curve-list .unit { color: var(--text-muted); font-size: 0.85rem; margin-left: auto; }

.results { display: flex; flex-direction: column; gap: 1.25rem; min-width: 0; }
.preview { padding: 0.5rem; }
.canvas-wrap { position: relative; }
#chart { display: block; width: 100%; height: auto; border-radius: 6px; }
.crosshair {
  position: absolute;
  width: 1px;
  background: rgba(11, 11, 11, 0.35);
  pointer-events: none;
}
.tooltip {
  position: absolute;
  pointer-events: none;
  background: #ffffff;
  color: #0b0b0b;
  border: 1px solid rgba(11, 11, 11, 0.12);
  border-radius: 8px;
  box-shadow: 0 4px 14px rgba(0, 0, 0, 0.12);
  padding: 0.45rem 0.6rem;
  font-size: 0.85rem;
  white-space: nowrap;
}
.tooltip .t-head { color: #52514e; margin-bottom: 0.2rem; }
.tooltip .t-row { display: flex; align-items: center; gap: 0.4rem; }
.tooltip .t-val { margin-left: auto; padding-left: 1rem; font-variant-numeric: tabular-nums; }

.kv { display: grid; grid-template-columns: max-content 1fr; gap: 0.3rem 1.25rem; margin: 0; }
.kv dt { color: var(--text-secondary); }
.kv dd { margin: 0; overflow-wrap: anywhere; }

table.data { border-collapse: collapse; width: 100%; font-size: 0.9rem; }
table.data th, table.data td { text-align: left; padding: 0.3rem 0.6rem 0.3rem 0; border-bottom: 1px solid var(--hairline); }
table.data th { color: var(--text-secondary); font-weight: 500; }
table.data .num { text-align: right; font-variant-numeric: tabular-nums; width: 6rem; }
details { margin-top: 0.75rem; }
summary { cursor: pointer; color: var(--text-secondary); }
pre {
  max-height: 420px;
  overflow: auto;
  background: var(--page);
  border-radius: 6px;
  padding: 0.75rem;
  font-size: 0.82rem;
}
.scroll { max-height: 420px; overflow: auto; }
.scroll-x { overflow-x: auto; }
#fraction-table td, #fraction-table th { white-space: nowrap; }

footer {
  max-width: 1500px;
  margin: 0 auto;
  padding: 1rem 2rem 2rem;
  color: var(--text-muted);
  font-size: 0.85rem;
}
footer a { color: inherit; }

h3 { margin: 1rem 0 0.25rem; font-size: 0.95rem; }
#inlet-table input { width: 100%; max-width: 22rem; }
#inlet-table td:first-child { width: 5rem; font-weight: 600; }
.phases { margin: 0.25rem 0 0; padding-left: 1.5rem; }
.phases li { margin: 0 0 0.75rem; }
.phases .ph-head { font-weight: 600; }
.phases .ph-meta { color: var(--text-secondary); font-size: 0.88rem; margin-left: 0.5rem; font-weight: 400; }
.phases ul { margin: 0.2rem 0 0; padding-left: 1.1rem; color: var(--text-secondary); font-size: 0.9rem; }
.phases ul li { margin: 0.1rem 0; }
.phases .use { color: var(--text-primary); }

.card-head { display: flex; align-items: center; justify-content: space-between; gap: 1rem; margin-bottom: 0.6rem; }
.card-head h2 { margin: 0; }
.preview .card-head { padding: 0.25rem 0.5rem 0; }
button.copy {
  font: 500 0.85rem var(--font);
  color: var(--text-secondary);
  background: var(--page);
  border: 1px solid var(--border);
  border-radius: 6px;
  padding: 0.25rem 0.7rem;
  cursor: pointer;
}
button.copy:hover { color: var(--text-primary); border-color: var(--text-muted); }
button.copy.done { color: var(--accent); border-color: var(--accent); }
details.buffers { margin: 0 0 0.5rem; }
.inlets { margin: 0.25rem 0 0; padding-left: 1.1rem; font-size: 0.92rem; }
.inlets li { margin: 0.15rem 0; }
.inlets .buf { font-weight: 600; }

.top-actions { display: flex; align-items: flex-start; gap: 0.6rem; }
.btn, .howto summary {
  font: 500 0.9rem var(--font);
  color: var(--text-primary);
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 8px;
  padding: 0.4rem 0.8rem;
  cursor: pointer;
}
.btn:hover, .howto summary:hover { border-color: var(--text-muted); }
.howto { position: relative; margin: 0; }
.howto summary { list-style: none; color: var(--text-primary); }
.howto summary::-webkit-details-marker { display: none; }
.howto[open] summary { border-color: var(--accent); }
.howto-panel {
  position: absolute;
  right: 0;
  top: calc(100% + 0.4rem);
  z-index: 10;
  width: 20rem;
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 10px;
  box-shadow: 0 6px 20px rgba(0, 0, 0, 0.12);
  padding: 0.75rem 1rem;
}
.howto-panel ol { margin: 0; padding-left: 1.2rem; }
.howto-panel li { margin: 0.2rem 0; }
.under-drop { display: flex; justify-content: flex-end; margin-top: 0.6rem; }