:root {
  --bg: #f6f8fc;
  --panel: #ffffff;
  --line: #d7deea;
  --text: #10223a;
  --accent: #2563eb;
  --accent-soft: #e9f0ff;
}

* {
  box-sizing: border-box;
}

body {
  margin: 0;
  font-family: "Segoe UI", Tahoma, sans-serif;
  background: radial-gradient(circle at 10% 0%, #eef3ff 0%, var(--bg) 45%);
  color: var(--text);
}

.app {
  max-width: 1200px;
  margin: 0 auto;
  padding: 18px;
}

.panel {
  background: var(--panel);
  border: 1px solid var(--line);
  border-radius: 14px;
  padding: 16px;
  margin-bottom: 14px;
  box-shadow: 0 8px 24px rgba(16, 34, 58, 0.05);
}

h1,
h2 {
  margin-top: 0;
}

h1 {
  margin-bottom: 10px;
  font-size: 28px;
}

h2 {
  margin-bottom: 12px;
  font-size: 20px;
}

p {
  margin: 0;
  line-height: 1.5;
}

.controls {
  display: grid;
  gap: 10px;
}

label {
  display: flex;
  flex-direction: column;
  gap: 6px;
  font-weight: 600;
}

input[type="number"],
input[type="range"],
button {
  font: inherit;
}

input[type="number"] {
  width: 100%;
  max-width: 240px;
  padding: 8px 10px;
  border: 1px solid var(--line);
  border-radius: 10px;
}

input[type="range"] {
  max-width: 360px;
}

.checkbox-line {
  flex-direction: row;
  align-items: center;
  gap: 8px;
}

.weight-row {
  display: flex;
  gap: 12px;
  flex-wrap: wrap;
}

.weight-row label {
  min-width: 190px;
}

.weight-row.disabled {
  opacity: 0.6;
}

button {
  width: fit-content;
  padding: 10px 16px;
  border-radius: 10px;
  border: 1px solid #1d4ed8;
  background: var(--accent);
  color: #fff;
  font-weight: 700;
  cursor: pointer;
}

button:hover {
  filter: brightness(1.05);
}

.layout {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 14px;
}

.graph-wrap {
  overflow: auto;
  border: 1px solid var(--line);
  border-radius: 10px;
  background: linear-gradient(180deg, #f9fbff, #f4f8ff);
}

svg {
  display: block;
  min-width: 580px;
}

.table-wrap {
  overflow: auto;
}

table {
  border-collapse: collapse;
  min-width: 480px;
}

th,
td {
  border: 1px solid var(--line);
  padding: 8px 10px;
  text-align: center;
}

th {
  background: var(--accent-soft);
  font-weight: 700;
}

td.diagonal {
  color: #5e6b7c;
}

.solution {
  line-height: 1.45;
}

.solution details {
  border: 1px solid var(--line);
  border-radius: 10px;
  background: #f8fbff;
  padding: 10px 12px;
}

.solution summary {
  cursor: pointer;
  font-weight: 700;
}

.solution ol {
  margin: 10px 0 0 20px;
  padding: 0;
}

.solution li {
  margin-bottom: 6px;
}

.solution .final-answer {
  margin-top: 8px;
  font-weight: 700;
}

@media (max-width: 980px) {
  .layout {
    grid-template-columns: 1fr;
  }
}