:root {
  --bg: #ffffff;
  --text: #0b1220;
  --muted: #5b677a;
  --line: #e6e9f0;
  --card: #f7f9fc;
  --btn: #2563eb;
  --btnText: #fff;
  --radius: 14px;
}

* {
  box-sizing: border-box;
}
body {
  margin: 0;
  font-family: system-ui, -apple-system, Segoe UI, Roboto, Arial, sans-serif;
  background: var(--bg);
  color: var(--text);
}

.wrap {
  max-width: 920px;
  margin: 0 auto;
  padding: 28px 16px 40px;
}
.head h1 {
  margin: 0 0 6px;
  font-size: 34px;
  letter-spacing: -0.02em;
}
.sub {
  margin: 0;
  color: var(--muted);
  line-height: 1.4;
}

.panel {
  margin-top: 18px;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 18px;
  background: #fff;
}

.row {
  display: flex;
  gap: 12px;
  flex-wrap: wrap;
}
.field {
  display: flex;
  flex-direction: column;
  gap: 6px;
  min-width: 240px;
  flex: 1;
}
.field span {
  font-weight: 650;
  font-size: 13px;
  color: var(--muted);
}
select,
input {
  padding: 12px 12px;
  border: 1px solid var(--line);
  border-radius: 12px;
  font-size: 15px;
  outline: none;
}
select:focus,
input:focus {
  border-color: #b6c4ff;
}

.help {
  margin: 12px 0 6px;
  color: var(--muted);
  font-size: 13px;
  line-height: 1.45;
}

.diagram {
  margin-top: 12px;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: var(--card);
  padding: 12px;
  display: flex;
  justify-content: center;
  align-items: center;
  min-height: 220px;
}
.diagram svg {
  width: 100%;
  height: 100%;
  max-width: 100%;
  max-height: 100%;
  display: block;
}

.inputs {
  margin-top: 12px;
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 12px;
}
@media (max-width: 640px) {
  .inputs {
    grid-template-columns: 1fr;
  }
}

.inputRow {
  display: flex;
  flex-direction: column;
  gap: 6px;
}

.inputGroup {
  display: flex;
  gap: 10px;
  align-items: stretch;
}
.inputGroup input {
  flex: 1;
  min-width: 0;
}
.unitSelect {
  width: 72px;
}
.inputRow .hint {
  color: var(--muted);
  font-size: 12px;
}

.actions {
  display: flex;
  gap: 10px;
  margin-top: 14px;
  flex-wrap: wrap;
}
.btn {
  padding: 12px 16px;
  border: 0;
  border-radius: 12px;
  background: var(--btn);
  color: var(--btnText);
  font-weight: 750;
  cursor: pointer;
}
.btn.ghost {
  background: #eef2ff;
  color: #1e2a58;
}
.btn:active {
  transform: translateY(1px);
}

.errors {
  margin-top: 10px;
  color: #b91c1c;
  font-weight: 600;
}

.results {
  margin-top: 18px;
  border-top: 1px solid var(--line);
  padding-top: 16px;
}
.results h2 {
  margin: 0 0 10px;
  font-size: 18px;
}

.resultGrid {
  display: grid;
  gap: 12px;
  grid-template-columns: repeat(3, minmax(0, 1fr));
}
@media (max-width: 900px) {
  .resultGrid {
    grid-template-columns: 1fr;
  }
}

.card {
  background: var(--card);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 14px;
}
.k {
  color: var(--muted);
  font-size: 12px;
  font-weight: 700;
}
.v {
  font-size: 22px;
  font-weight: 850;
  margin-top: 6px;
}
.s {
  color: var(--muted);
  margin-top: 4px;
}

.list {
  margin: 10px 0 0;
  padding-left: 18px;
}
.mono {
  font-family: ui-monospace, SFMono-Regular, Menlo, monospace;
  white-space: pre-wrap;
}

.foot {
  margin-top: 18px;
  color: var(--muted);
}