:root {
  --bg: #121417;
  --panel: #1a1d22;
  --panel-2: #22262d;
  --border: #2e333c;
  --text: #e7e9ec;
  --muted: #9aa1ab;
  --accent: #ff7a1a;
  --accent-2: #ffb020;
  --danger: #ff5c5c;
  --ok: #3ddc84;
  --font-sans: system-ui, -apple-system, "Segoe UI", Roboto, sans-serif;
  --font-mono: ui-monospace, "JetBrains Mono", "Cascadia Mono", Consolas, monospace;
  --radius: 0.5rem;
  --gap: 1rem;
  --header-h: 3.75rem;
  --fs-h3: 1rem;
  --fs-h2: 1.5rem;
  --fs-h1: 2rem;
  color-scheme: dark;
}

* { box-sizing: border-box; }

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

h1, h2, h3 { font-weight: 600; }
h2 { font-size: var(--fs-h2); }
h3, .panel-title { font-size: var(--fs-h3); color: var(--muted); border-bottom: 1px solid var(--border); padding-bottom: 0.3rem; }

.app-header {
  position: sticky;
  top: 0;
  z-index: 10;
  height: var(--header-h);
  display: flex;
  align-items: center;
  padding: 0 1.25rem;
  background: linear-gradient(180deg, var(--panel-2), var(--panel));
  border-bottom: 2px solid var(--accent);
}

.app-header h1 {
  margin: 0;
  font-size: var(--fs-h1);
  letter-spacing: 0.02em;
  color: var(--accent-2);
}

.app-header .icon-button {
  margin-left: auto;
}

.icon-button {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 2.25rem;
  height: 2.25rem;
  padding: 0;
  background: transparent;
  border: 1px solid transparent;
  color: var(--muted);
  border-radius: 50%;
}

.icon-button:hover {
  color: var(--accent-2);
  border-color: var(--border);
}

.layout {
  display: grid;
  gap: var(--gap);
  max-width: 1400px;
  margin: 0 auto;
  padding: var(--gap);
}

.result-col { position: relative; }

@media (min-width: 1024px) {
  .layout { grid-template-columns: minmax(20rem, 26rem) 1fr; align-items: start; }
  .result-col {
    position: sticky;
    top: var(--header-h);
    max-height: calc(100vh - var(--header-h));
    overflow-y: auto;
  }
}

.kpis {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: var(--gap);
  margin-bottom: 1rem;
}

.kpi {
  display: flex;
  flex-direction: column;
  gap: 0.25rem;
  background: var(--panel);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 0.9rem 1rem;
  text-align: center;
}

.kpi-value {
  font-family: var(--font-mono);
  font-variant-numeric: tabular-nums;
  font-size: var(--fs-h1);
  color: var(--accent-2);
}

.kpi-label {
  color: var(--muted);
  font-size: 0.8rem;
}

.chart { height: 18rem; }

details.table-details {
  margin-top: 0.5rem;
}

details.table-details summary {
  cursor: pointer;
  color: var(--muted);
  font-size: 0.85rem;
}

details.table-details table { margin-top: 0.6rem; }

.panel {
  background: var(--panel);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 1rem;
  margin-bottom: 1rem;
}

.inputs-col details {
  background: var(--panel);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  margin-bottom: 0.75rem;
  overflow: hidden;
}

.inputs-col details > summary {
  list-style: none;
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 0.7rem 1rem;
  background: var(--panel-2);
  font-weight: 600;
}

.inputs-col details > summary::-webkit-details-marker { display: none; }

.inputs-col details > summary::after {
  content: "▾";
  color: var(--accent);
  transition: transform 0.15s ease;
}

.inputs-col details[open] > summary::after { transform: rotate(180deg); }

.inputs-col details fieldset {
  border: 0;
  margin: 0;
  padding: 1rem;
  display: flex;
  flex-direction: column;
  gap: 0.6rem;
}

.inputs-col label {
  display: flex;
  flex-direction: column;
  gap: 0.2rem;
}

.inputs-col label span {
  color: var(--muted);
  font-size: 0.8rem;
}

input[type="number"], input[type="file"] {
  background: var(--panel-2);
  border: 1px solid var(--border);
  color: var(--text);
  border-radius: 0.35rem;
  padding: 0.4rem 0.55rem;
  font-family: var(--font-mono);
  width: 100%;
}

input:focus-visible {
  outline: 2px solid var(--accent);
  outline-offset: 1px;
  border-color: var(--accent);
}

button {
  background: var(--panel-2);
  color: var(--text);
  border: 1px solid var(--border);
  border-radius: 0.35rem;
  padding: 0.4rem 0.8rem;
  cursor: pointer;
}

button:hover { border-color: var(--accent); }
button:focus-visible { outline: 2px solid var(--accent); outline-offset: 1px; }

.error { display: block; color: var(--danger); min-height: 1.2em; font-size: 0.85em; }

table { border-collapse: collapse; margin-bottom: 1rem; width: 100%; }
th, td { border: 1px solid var(--border); padding: 0.3rem 0.6rem; text-align: right; }
th:first-child, td:first-child { text-align: left; }
th { color: var(--muted); font-weight: 600; }
td:not(:first-child) { font-family: var(--font-mono); font-variant-numeric: tabular-nums; }
tfoot { font-weight: 600; }

#result.is-stale { opacity: 0.35; filter: grayscale(1); pointer-events: none; transition: opacity 0.2s; }

#blocked {
  position: absolute;
  top: 2rem;
  left: 1rem;
  right: 1rem;
  z-index: 1;
  margin: 0;
  padding: 0.75rem 1rem;
  background: var(--panel);
  border: 1px solid var(--danger);
  border-radius: var(--radius);
  color: var(--danger);
  font-weight: 600;
  text-align: center;
}

[hidden] { display: none; }

dialog.drawer {
  position: fixed;
  inset: 0 0 0 auto;
  width: min(28rem, 100vw);
  height: 100vh;
  max-height: none;
  margin: 0;
  padding: 1.25rem;
  background: var(--panel);
  border: 0;
  border-left: 1px solid var(--border);
  color: var(--text);
  overflow-y: auto;
  animation: drawer-in 0.2s ease-out;
}

dialog.drawer::backdrop {
  background: rgba(10, 11, 13, 0.6);
}

@keyframes drawer-in {
  from { transform: translateX(100%); }
  to { transform: translateX(0); }
}

.drawer-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: 1rem;
}

.drawer-header h2 {
  margin: 0;
  font-size: var(--fs-h2);
}

dialog.drawer fieldset {
  border: 0;
  margin: 0 0 1rem;
  padding: 1rem;
  background: var(--panel-2);
  border-radius: var(--radius);
  display: flex;
  flex-direction: column;
  gap: 0.6rem;
}

dialog.drawer legend {
  color: var(--muted);
  font-weight: 600;
  padding: 0 0.3rem;
}

dialog.drawer label {
  display: flex;
  flex-direction: column;
  gap: 0.2rem;
}

dialog.drawer label span {
  color: var(--muted);
  font-size: 0.8rem;
}

/* --- Hero: ladle + composition donut --- */

.hero {
  display: grid;
  gap: var(--gap);
  margin-bottom: 1rem;
}

@media (min-width: 1024px) {
  .hero { grid-template-columns: 1fr 1fr; }
  .hero-donut { order: 1; }
}

#ladle {
  width: 100%;
  height: 18rem;
}

.ladle-wall {
  stroke: var(--border);
  stroke-width: 4;
}

#ladle-steel-labels text,
#ladle-slag-label {
  font-family: var(--font-mono);
  font-size: 13px;
  fill: var(--text);
  paint-order: stroke;
  stroke: rgba(0, 0, 0, 0.55);
  stroke-width: 3px;
}

#ladle-slag {
  transition: y 0.4s ease, height 0.4s ease, fill 0.4s ease;
}

/* --- Dumbbell: mixed -> result -> equilibrium --- */

.dumbbell-legend {
  display: flex;
  flex-wrap: wrap;
  gap: 1rem;
  color: var(--muted);
  font-size: 0.8rem;
  margin-bottom: 0.75rem;
}

.dumbbell-legend i {
  display: inline-block;
  width: 0.65rem;
  height: 0.65rem;
  border-radius: 50%;
  margin-right: 0.35rem;
  vertical-align: middle;
}

.dumbbell-legend .dot-mixed { border: 2px solid var(--muted); }
.dumbbell-legend .dot-eq { background: var(--muted); }
.dumbbell-legend .dot-result { background: var(--accent); }

ul.dumbbell {
  list-style: none;
  margin: 0 0 0.5rem;
  padding: 0;
}

.dumbbell li {
  display: grid;
  grid-template-columns: 5rem 1fr 14rem;
  align-items: center;
  gap: 0.75rem;
  padding: 0.4rem 0;
  border-bottom: 1px solid var(--border);
}

.dumbbell li:last-child { border-bottom: 0; }

.dumbbell-label { color: var(--muted); font-size: 0.85rem; }

.dumbbell-value {
  font-family: var(--font-mono);
  font-variant-numeric: tabular-nums;
  font-size: 0.85rem;
  text-align: right;
  white-space: nowrap;
}

.track {
  position: relative;
  height: 2px;
  background: var(--border);
}

.track span {
  position: absolute;
  top: 50%;
  width: 0.7rem;
  height: 0.7rem;
  border-radius: 50%;
  transform: translate(-50%, -50%);
}

.dot-mixed { border: 2px solid var(--muted); background: var(--panel); }
.dot-eq { background: var(--muted); }
.dot-result { background: var(--accent); z-index: 1; }

#dumbbell-note {
  color: var(--danger);
  font-size: 0.85rem;
}

/* --- Threshold gauges --- */

ul#gauges {
  list-style: none;
  margin: 0 0 1rem;
  padding: 0;
}

.gauge {
  display: grid;
  grid-template-columns: 4.5rem 1fr 11rem;
  align-items: center;
  gap: 0.75rem;
  padding: 0.4rem 0;
}

.gauge-label { color: var(--muted); font-size: 0.85rem; }

.gauge-value {
  font-family: var(--font-mono);
  font-variant-numeric: tabular-nums;
  font-size: 0.85rem;
  text-align: right;
}

.gauge small {
  grid-column: 1 / -1;
  color: var(--danger);
  font-size: 0.8rem;
}

.gauge-track {
  position: relative;
  height: 0.6rem;
  background: var(--panel-2);
  border-radius: 0.3rem;
  overflow: visible;
}

.gauge-fill {
  height: 100%;
  border-radius: 0.3rem;
  background: var(--ok);
}

.gauge.is-over .gauge-fill {
  background: var(--danger);
}

.gauge-mark {
  position: absolute;
  top: -0.15rem;
  width: 2px;
  height: 0.9rem;
  background: var(--text);
  transform: translateX(-1px);
}

.chart-note {
  color: var(--muted);
  font-size: 0.85rem;
  line-height: 1.5;
  margin: 0 0 0.75rem;
}

.chart-legend {
  list-style: none;
  margin: 0 0 0.5rem;
  padding: 0;
  display: grid;
  gap: 0.35rem;
  font-size: 0.8rem;
  color: var(--muted);
}

.chart-legend b { color: var(--text); font-weight: 600; }

.chart-legend i {
  display: inline-block;
  width: 0.8rem;
  height: 0.8rem;
  border-radius: 2px;
  margin-right: 0.45rem;
  vertical-align: -0.1rem;
}

.chart-legend .swatch-total {
  width: 0.6rem;
  height: 0.6rem;
  background: var(--text);
  transform: rotate(45deg);
  margin-left: 0.1rem;
}

.slag-scale-legend {
  display: flex;
  align-items: center;
  gap: 0.6rem;
  font-size: 0.75rem;
  color: var(--muted);
  line-height: 1.3;
}

.slag-scale-legend span:last-child { text-align: right; }

.slag-scale-legend i {
  flex: 1;
  height: 0.6rem;
  border-radius: 0.3rem;
  border: 1px solid var(--border);
}

#warnings .no-warnings { color: var(--muted); list-style: none; }