:root {
  --paper: #fbf3e2;
  --paper-2: #f7eed9;
  --card: #fffaf0;
  --ink: #4a3f2f;
  --ink-soft: #6b5740;
  --line: #e3d4b6;
  --line-2: #d8c39a;
  --blue: #2c5f8a;
  --red: #b03a2e;
  --gold: #8a6d3b;
  --green: #2c8a5f;
}

* {
  box-sizing: border-box;
}

html,
body {
  margin: 0;
  padding: 0;
}

body {
  background: var(--paper);
  color: var(--ink);
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC",
    "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
  line-height: 1.5;
}

.app {
  max-width: 1180px;
  margin: 0 auto;
  padding: 20px 16px 40px;
}

.header {
  text-align: center;
  padding: 12px 0 18px;
  border-bottom: 2px solid var(--line-2);
  margin-bottom: 20px;
}

.header h1 {
  margin: 0 0 6px;
  font-size: 26px;
  letter-spacing: 2px;
  color: var(--ink);
}

.subtitle {
  margin: 0;
  font-size: 13px;
  color: var(--ink-soft);
}

.layout {
  display: grid;
  grid-template-columns: 340px 1fr;
  gap: 18px;
  align-items: start;
}

.panel {
  background: var(--card);
  border: 1px solid var(--line);
  border-radius: 12px;
  padding: 16px;
  box-shadow: 0 2px 10px rgba(120, 90, 40, 0.06);
}

.params-panel {
  position: sticky;
  top: 16px;
}

.panel h2 {
  margin: 0 0 12px;
  font-size: 16px;
  color: var(--gold);
  border-left: 4px solid var(--red);
  padding-left: 8px;
}

/* 参数滑块 */
.params {
  display: flex;
  flex-direction: column;
  gap: 12px;
}

.param {
  font-size: 12px;
}

.param .row {
  display: flex;
  justify-content: space-between;
  align-items: baseline;
  margin-bottom: 2px;
}

.param .label {
  color: var(--ink);
  font-weight: 600;
}

.param .val {
  color: var(--blue);
  font-variant-numeric: tabular-nums;
  font-weight: 700;
}

.param .desc {
  color: var(--ink-soft);
  font-size: 11px;
  margin: 2px 0 4px;
}

.param input[type="range"] {
  width: 100%;
  accent-color: var(--red);
  margin: 0;
}

/* 按钮 */
.actions {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin-top: 16px;
}

.btn {
  flex: 1 1 auto;
  border: 1px solid var(--line-2);
  background: var(--paper-2);
  color: var(--ink);
  padding: 9px 10px;
  border-radius: 8px;
  font-size: 13px;
  cursor: pointer;
  transition: all 0.15s;
}

.btn:hover {
  border-color: var(--gold);
}

.btn-primary {
  background: var(--red);
  border-color: var(--red);
  color: #fff;
  font-weight: 600;
}

.btn-primary:hover {
  background: #972f25;
}

.btn-ghost {
  background: transparent;
}

/* 结果面板 */
.result-panel {
  display: flex;
  flex-direction: column;
  gap: 18px;
}

.card {
  background: var(--card);
  border: 1px solid var(--line);
  border-radius: 12px;
  padding: 16px;
}

.card h2 {
  margin: 0 0 10px;
  font-size: 16px;
  color: var(--gold);
  border-left: 4px solid var(--blue);
  padding-left: 8px;
}

#chart {
  display: block;
  width: 100%;
  background: var(--paper);
  border: 1px solid var(--line-2);
  border-radius: 8px;
}

.hint {
  margin: 8px 0 0;
  font-size: 11px;
  color: var(--ink-soft);
}

/* 统计 */
.stats {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(120px, 1fr));
  gap: 10px;
}

.stats.empty,
.dynasties.empty {
  color: var(--ink-soft);
  font-size: 13px;
}

.stat {
  background: var(--paper);
  border: 1px solid var(--line-2);
  border-radius: 8px;
  padding: 10px 12px;
  text-align: center;
}

.stat .num {
  font-size: 22px;
  font-weight: 700;
  color: var(--blue);
  font-variant-numeric: tabular-nums;
}

.stat .cap {
  font-size: 11px;
  color: var(--ink-soft);
  margin-top: 2px;
}

.reason-tags {
  grid-column: 1 / -1;
  display: flex;
  flex-wrap: wrap;
  gap: 6px;
}

.tag {
  font-size: 11px;
  padding: 3px 8px;
  border-radius: 12px;
  color: #fff;
}

/* 朝代列表 */
.dynasties {
  display: flex;
  flex-direction: column;
  gap: 8px;
}

.dynasty {
  display: flex;
  align-items: center;
  gap: 10px;
  padding: 8px 10px;
  background: var(--paper);
  border: 1px solid var(--line-2);
  border-radius: 8px;
}

.dynasty .name {
  font-weight: 700;
  color: var(--gold);
  min-width: 44px;
}

.dynasty .meta {
  font-size: 12px;
  color: var(--ink-soft);
  flex: 1;
}

.dynasty .meta b {
  color: var(--ink);
}

.reason {
  font-size: 11px;
  padding: 2px 8px;
  border-radius: 10px;
  color: #fff;
  white-space: nowrap;
}

/* 页脚 */
.footer {
  margin-top: 24px;
}

.footer details {
  background: var(--card);
  border: 1px solid var(--line);
  border-radius: 10px;
  padding: 10px 14px;
}

.series {
  margin-top: 16px;
  background: var(--card);
  border: 1px solid var(--line);
  border-radius: 10px;
  padding: 12px 14px;
}

.series h2 {
  margin: 0 0 10px;
  font-size: 15px;
  color: var(--gold);
  border-left: 4px solid var(--blue);
  padding-left: 8px;
}

.series-list {
  margin: 0;
  padding: 0;
  list-style: none;
  display: flex;
  flex-direction: column;
  gap: 8px;
}

.series-list a {
  color: var(--blue);
  text-decoration: none;
  font-size: 13px;
  border-bottom: 1px dashed var(--line-2);
  padding-bottom: 2px;
  transition: color 0.15s;
}

.series-list a:hover {
  color: var(--red);
}

.footer summary {
  cursor: pointer;
  font-size: 13px;
  color: var(--gold);
  font-weight: 600;
}

.formula {
  margin-top: 10px;
  font-size: 12px;
  color: var(--ink-soft);
}

.formula p {
  margin: 6px 0;
}

.formula code {
  background: var(--paper-2);
  padding: 1px 5px;
  border-radius: 4px;
  color: var(--blue);
  font-size: 12px;
}

.formula .src {
  border-top: 1px dashed var(--line-2);
  padding-top: 8px;
  color: var(--ink-soft);
}

/* 响应式 */
@media (max-width: 820px) {
  .layout {
    grid-template-columns: 1fr;
  }
  .params-panel {
    position: static;
  }
}