* {
  box-sizing: border-box;
}

body {
  margin: 0;
  padding: 24px;
  font-family: "Segoe UI", "Microsoft YaHei", sans-serif;
  background: #f6f7f9;
  color: #24292f;
}

header h1 {
  margin: 0 0 8px;
  font-size: 22px;
}

/* 页头首行：蒙特卡洛状态贴着标题右侧，留少量空白 */
.header-row {
  display: flex;
  align-items: baseline;
  gap: 24px;
}

.header-row h1 {
  margin: 0;
  white-space: nowrap;
}

.subtitle {
  margin: 0 0 16px;
  /* max-width: 900px; */
  color: #57606a;
  font-size: 13px;
  line-height: 1.6;
}

.legend-note {
  padding: 1px 6px;
  border-radius: 4px;
}

.note-blue {
  color: #2563eb;
  background: #eff6ff;
}

.note-yellow {
  color: #a16207;
  background: #fefce8;
}

.note-orange {
  color: #c2410c;
  background: #fff7ed;
}

.note-gray {
  color: #57606a;
  background: #f6f8fa;
}

.note-green {
  color: #15803d;
  background: #f0fdf4;
}

.note-red {
  color: #b91c1c;
  background: #fef2f2;
}

.controls {
  display: flex;
  flex-wrap: wrap;
  gap: 24px;
  align-items: center;
  padding: 12px 16px;
  background: #fff;
  border: 1px solid #d0d7de;
  border-radius: 8px;
  margin-bottom: 16px;
}

.control {
  display: flex;
  align-items: center;
  gap: 10px;
}

.control label {
  font-size: 14px;
  white-space: nowrap;
}

/* K 滑杆组：basis 较大，宽屏下挤不开时与 MC 控制组分行，
   滑杆随窗口宽度弹性伸长（K 跨 ~12 个数量级，需要精细定位） */
.control-slider {
  flex: 1 1 460px;
}

.control-slider input[type="range"] {
  flex: 1;
  width: auto;
  min-width: 200px;
}

/* N 只有 64~8192（约 2 个数量级），滑杆固定小宽度即可 */
#sliderN {
  width: 220px;
}

.control input[type="number"] {
  width: 64px;
  padding: 4px 6px;
  border: 1px solid #d0d7de;
  border-radius: 6px;
  font-size: 14px;
}

/* K 上限 N³（8192³ ≈ 5.5e11，12 位数字），输入框需要更宽 */
#inputK {
  width: 130px;
}

.control-mc {
  flex-wrap: wrap;
}

.control-mc button {
  padding: 4px 12px;
  border: 1px solid #d0d7de;
  border-radius: 6px;
  background: #f6f8fa;
  font-size: 13px;
  cursor: pointer;
}

.control-mc button:hover:not(:disabled) {
  background: #eaeef2;
}

.control-mc button:disabled {
  color: #8c959f;
  cursor: not-allowed;
}

.control-mc select {
  padding: 3px 6px;
  border: 1px solid #d0d7de;
  border-radius: 6px;
  font-size: 13px;
}

.control-mc input[type="number"] {
  width: 70px;
  font-size: 13px;
}

.mc-status {
  margin: 0;
  font-size: 12px;
  color: #57606a;
  line-height: 1.6;
  min-height: 1.2em;
  text-align: right;
}

main {
  display: grid;
  grid-template-columns: 1fr;
  gap: 16px;
}

.chart-wrap {
  background: #fff;
  border: 1px solid #d0d7de;
  border-radius: 8px;
  padding: 12px;
}

.chart {
  width: 100%;
  height: 420px;
}

.chart-note {
  margin: 8px 4px 0;
  font-size: 12px;
  color: #57606a;
  line-height: 1.6;
}