:root {
  font-family: Inter, Segoe UI, Roboto, Arial, sans-serif;
  color: #1f2937;
  background: #f3f4f6;
}

* { box-sizing: border-box; }

body {
  margin: 0;
  min-height: 100vh;
  background: #f3f4f6;
}

.topbar {
  padding: 1rem 1.25rem;
  border-bottom: 1px solid #d1d5db;
  background: white;
}

.topbar h1 {
  margin: 0;
  font-size: 1.45rem;
}

.topbar p {
  margin: 0.25rem 0 0;
  color: #4b5563;
}

button,
select,
input[type="text"],
input[type="date"],
input[type="number"] {
  border: 1px solid #9ca3af;
  background: #f9fafb;
  color: #111827;
  border-radius: 0.5rem;
  padding: 0.45rem 0.7rem;
  font-size: 0.85rem;
}

button { cursor: pointer; }
input[type="file"] { font-size: 0.78rem; }

.inline-control {
  display: inline-flex;
  align-items: center;
  gap: 0.4rem;
  font-size: 0.9rem;
}

.hint {
  margin: 0.2rem 0 0;
  font-size: 0.74rem;
  color: #6b7280;
}

.element-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem;
}

.calc-layout {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 1rem;
  padding: 1rem;
  align-items: start;
}

.calc-panel {
  background: white;
  border: 1px solid #d1d5db;
  border-radius: 0.75rem;
  padding: 1rem;
}

.calc-panel h2 {
  margin: 0 0 0.5rem;
  font-size: 1rem;
}

.calc-grid {
  display: grid;
  grid-template-columns: repeat(2, minmax(180px, 1fr));
  gap: 0.6rem;
  margin-bottom: 0.75rem;
}

.calc-grid label {
  display: grid;
  gap: 0.2rem;
  font-size: 0.83rem;
  color: #374151;
}

details {
  border: 1px solid #d1d5db;
  border-radius: 0.5rem;
  padding: 0.35rem 0.45rem;
  background: #fff;
}

summary {
  cursor: pointer;
  font-weight: 600;
  font-size: 0.84rem;
  color: #334155;
}

#segmentTableWrap table {
  width: 100%;
  border-collapse: collapse;
  font-size: 0.82rem;
}

#segmentTableWrap th,
#segmentTableWrap td {
  border: 1px solid #d1d5db;
  padding: 0.35rem 0.45rem;
  text-align: left;
}

#segmentTableWrap th { background: #f8fafc; }

.calc-summary {
  margin-top: 0.8rem;
  padding: 0.75rem;
  border-radius: 0.6rem;
  border: 1px solid #cbd5e1;
  background: #f8fafc;
  font-size: 0.9rem;
  line-height: 1.45;
}

.calc-summary strong { color: #0f172a; }

.practice-values {
  margin-top: 0.85rem;
  border: 1px solid #cbd5e1;
  border-radius: 0.6rem;
  padding: 0.6rem 0.75rem;
  background: #f8fafc;
}

.practice-values summary {
  cursor: pointer;
  font-weight: 600;
  color: #0f172a;
}

.practice-values h3 {
  margin: 0.8rem 0 0.35rem;
  font-size: 0.88rem;
  color: #1e293b;
}

.practice-grid table {
  width: 100%;
  border-collapse: collapse;
  font-size: 0.78rem;
  background: #ffffff;
}

.practice-grid th,
.practice-grid td {
  border: 1px solid #d1d5db;
  padding: 0.3rem 0.4rem;
  text-align: left;
  vertical-align: top;
}

.practice-grid th { background: #f1f5f9; }

.practice-values ul {
  margin: 0.2rem 0 0.55rem 1.1rem;
  padding: 0;
  font-size: 0.8rem;
  color: #334155;
}

#segmentTableWrap input[type="text"],
#segmentTableWrap input[type="number"] {
  width: 100%;
  min-width: 70px;
  padding: 0.2rem 0.35rem;
  font-size: 0.78rem;
}

.segment-actions {
  display: flex;
  gap: 0.25rem;
}

.segment-actions button {
  padding: 0.2rem 0.45rem;
  font-size: 0.76rem;
}

.segment-label-cell {
  display: grid;
  gap: 0.2rem;
}

.segment-size-hint {
  color: #475569;
  font-size: 0.72rem;
}

.network-graph-wrap {
  margin-top: 0.7rem;
  border: 1px solid #d1d5db;
  border-radius: 0.55rem;
  background: #fff;
  padding: 0.45rem;
  overflow: auto;
}

.network-graph-wrap svg {
  width: 100%;
  min-height: 220px;
  display: block;
}

@media (max-width: 1080px) {
  .calc-layout { grid-template-columns: 1fr; }
  .calc-grid { grid-template-columns: 1fr; }
}