:root {
  --bg: #f5f7f7;
  --panel: #ffffff;
  --panel-soft: #f0f4f2;
  --ink: #14201d;
  --muted: #60706b;
  --line: #d9e0dd;
  --accent: #007a6f;
  --accent-strong: #005f56;
  --accent-soft: #dcefeb;
  --rose: #aa365c;
  --amber: #9a6a13;
  --danger: #9f2636;
  --shadow: 0 12px 36px rgba(20, 32, 29, 0.08);
}

* {
  box-sizing: border-box;
}

[hidden] {
  display: none !important;
}

body {
  margin: 0;
  color: var(--ink);
  background: var(--bg);
  font-family: "Avenir Next", "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", Arial, sans-serif;
  line-height: 1.45;
}

button,
input,
select {
  font: inherit;
}

button {
  border: 0;
}

.topbar {
  position: sticky;
  top: 0;
  z-index: 20;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 20px;
  min-height: 72px;
  padding: 14px max(24px, 4vw);
  background: rgba(245, 247, 247, 0.92);
  border-bottom: 1px solid var(--line);
  backdrop-filter: blur(14px);
}

.brand {
  display: flex;
  align-items: center;
  gap: 12px;
  min-width: 0;
}

.brand-mark {
  display: grid;
  width: 42px;
  height: 42px;
  place-items: center;
  color: #fff;
  background: var(--accent);
  border-radius: 8px;
  font-size: 26px;
  font-weight: 800;
}

.brand h1 {
  margin: 0;
  font-size: 22px;
  line-height: 1.05;
}

.brand p {
  margin: 2px 0 0;
  color: var(--muted);
  font-size: 13px;
}

.language-switch {
  display: inline-flex;
  flex: 0 0 auto;
  padding: 3px;
  background: var(--panel);
  border: 1px solid var(--line);
  border-radius: 8px;
  box-shadow: 0 4px 16px rgba(20, 32, 29, 0.06);
}

.language-switch button {
  min-width: 78px;
  padding: 7px 10px;
  color: var(--muted);
  background: transparent;
  border-radius: 6px;
  cursor: pointer;
}

.language-switch button.active {
  color: #fff;
  background: var(--accent);
}

/* Topbar nav tabs (Simulator | Knowledge) */
.topbar-nav {
  display: flex;
  gap: 6px;
}

.nav-tab {
  padding: 8px 18px;
  color: var(--muted);
  background: transparent;
  border-radius: 8px;
  font-size: 14px;
  font-weight: 700;
  text-decoration: none;
  transition: background 0.15s, color 0.15s;
}

.nav-tab:hover {
  background: var(--panel-soft);
  color: var(--ink);
}

.nav-tab.active {
  color: #fff;
  background: var(--accent);
}

.topbar-actions {
  display: flex;
  align-items: center;
  gap: 12px;
  flex: 0 0 auto;
}

.nav-link,
.more-link {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 7px;
  min-height: 34px;
  padding: 7px 10px;
  color: var(--accent-strong);
  background: var(--accent-soft);
  border: 1px solid #c6ddd8;
  border-radius: 6px;
  font-size: 13px;
  font-weight: 800;
  text-decoration: none;
  white-space: nowrap;
}

.nav-link:hover,
.more-link:hover {
  color: #fff;
  background: var(--accent);
}

.nav-link svg,
.more-link svg {
  width: 16px;
  height: 16px;
}

.workspace {
  display: grid;
  grid-template-columns: minmax(360px, 520px) minmax(0, 1fr);
  gap: 18px;
  width: min(1500px, calc(100vw - 32px));
  margin: 18px auto 32px;
}

.panel {
  min-width: 0;
  padding: 18px;
  background: var(--panel);
  border: 1px solid var(--line);
  border-radius: 8px;
  box-shadow: var(--shadow);
}

.panel-heading,
.block-heading {
  display: flex;
  align-items: baseline;
  justify-content: space-between;
  gap: 12px;
  margin-bottom: 14px;
}

h2,
h3 {
  margin: 0;
  line-height: 1.15;
}

h2 {
  font-size: 19px;
}

h3 {
  font-size: 15px;
}

.meta-line,
.status-line {
  color: var(--muted);
  font-size: 12px;
}

.cpu-note {
  margin-left: auto;
  text-align: right;
  white-space: nowrap;
  font-style: italic;
}

.control-group {
  margin: 0 0 16px;
  padding: 14px;
  border: 1px solid var(--line);
  border-radius: 8px;
}

.control-group legend {
  padding: 0 8px;
  color: var(--accent-strong);
  font-size: 13px;
  font-weight: 800;
}

.method-switch {
  display: flex;
  margin-bottom: 16px;
  border: 1px solid var(--line);
  border-radius: 8px;
  overflow: hidden;
}

.method-tab {
  flex: 1 1 0;
  min-height: 42px;
  padding: 9px 12px;
  color: var(--muted);
  background: var(--panel-soft);
  cursor: pointer;
  font-size: 13px;
  font-weight: 700;
  text-align: center;
  border-right: 1px solid var(--line);
  transition: background 0.15s, color 0.15s;
}

.method-tab:last-child {
  border-right: 0;
}

.method-tab.active {
  color: #fff;
  background: var(--accent);
}

.method-tab:hover:not(.active) {
  background: #e6eeeb;
}

.feasibility-badge {
  color: var(--accent-strong) !important;
  font-size: 17px !important;
  margin-top: 4px;
}

.two-column {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 12px;
}

.toolbar-row {
  display: flex;
  align-items: end;
  gap: 10px;
  margin-bottom: 10px;
}

.compact-row {
  align-items: end;
}

.field {
  display: grid;
  gap: 6px;
  min-width: 0;
}

.field.grow {
  flex: 1 1 auto;
}

.field.short {
  width: 92px;
}

.field.wide {
  grid-column: 1 / -1;
}

.field span {
  color: var(--muted);
  font-size: 12px;
  font-weight: 700;
}

.hint {
  display: block;
  color: #697873;
  font-size: 11px;
  line-height: 1.35;
}

.block-hint {
  margin: 0 0 8px;
}

input,
select {
  width: 100%;
  min-height: 38px;
  padding: 7px 9px;
  color: var(--ink);
  background: #fff;
  border: 1px solid #cfd8d4;
  border-radius: 6px;
  outline: none;
}

input:focus,
select:focus {
  border-color: var(--accent);
  box-shadow: 0 0 0 3px rgba(0, 122, 111, 0.14);
}

input[type="range"] {
  min-height: 28px;
  padding: 0;
  accent-color: var(--accent);
}

.slider-field {
  grid-template-columns: 1fr auto;
  align-items: center;
}

.slider-field span,
.slider-field input {
  grid-column: 1 / -1;
}

.slider-field output {
  justify-self: end;
  color: var(--accent-strong);
  font-weight: 800;
}

.slider-field .hint {
  grid-column: 1 / -1;
}

.icon-button,
.primary-button {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 7px;
  min-height: 38px;
  padding: 8px 12px;
  color: #fff;
  background: var(--accent);
  border-radius: 6px;
  cursor: pointer;
  white-space: nowrap;
}

.icon-button:hover,
.primary-button:hover {
  background: var(--accent-strong);
}

.icon-button.ghost {
  color: var(--ink);
  background: var(--panel-soft);
  border: 1px solid var(--line);
}

.icon-button.ghost:hover {
  background: #e6eeeb;
}

.icon-button svg,
.primary-button svg {
  width: 17px;
  height: 17px;
}

.primary-button {
  min-width: 160px;
  min-height: 44px;
  font-weight: 800;
}

.primary-button:disabled {
  cursor: wait;
  opacity: 0.68;
}

.stock-results {
  display: grid;
  max-height: 192px;
  overflow: auto;
  border: 1px solid var(--line);
  border-radius: 8px;
}

.stock-row {
  display: grid;
  grid-template-columns: 1fr auto auto;
  align-items: center;
  gap: 10px;
  min-height: 38px;
  padding: 7px 9px;
  border-bottom: 1px solid var(--line);
}

.stock-row:last-child {
  border-bottom: 0;
}

.stock-row strong {
  letter-spacing: 0;
}

.stock-row small {
  color: var(--muted);
}

.stock-row button {
  width: 30px;
  height: 30px;
  color: var(--accent);
  background: var(--accent-soft);
  border-radius: 6px;
  cursor: pointer;
}

.stock-row button.selected {
  color: #fff;
  background: var(--rose);
}

.selected-header {
  display: flex;
  justify-content: space-between;
  margin: 12px 0 8px;
  color: var(--muted);
  font-size: 12px;
  font-weight: 700;
}

.chip-list {
  display: flex;
  flex-wrap: wrap;
  gap: 6px;
  min-height: 34px;
  max-height: 200px;
  overflow-y: auto;
  padding: 2px;
}

.chip {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  height: 30px;
  padding: 0 5px 0 9px;
  color: var(--ink);
  background: var(--panel-soft);
  border: 1px solid var(--line);
  border-radius: 6px;
  font-size: 13px;
  font-weight: 800;
}

.chip button {
  display: grid;
  width: 21px;
  height: 21px;
  place-items: center;
  color: var(--muted);
  background: transparent;
  border-radius: 5px;
  cursor: pointer;
}

.chip button:hover {
  color: #fff;
  background: var(--rose);
}

.run-row {
  display: flex;
  align-items: center;
  gap: 12px;
}

.advanced-control {
  margin: 0 0 16px;
  padding: 0;
  border: 1px solid var(--line);
  border-radius: 8px;
  background: #fbfcfc;
}

.advanced-control summary {
  padding: 12px 14px;
  color: var(--accent-strong);
  font-size: 13px;
  font-weight: 800;
  cursor: pointer;
}

.advanced-grid {
  padding: 0 14px 14px;
}

.status-line.error {
  color: var(--danger);
  font-weight: 800;
}

.status-line.ok {
  color: var(--accent-strong);
  font-weight: 800;
}

.warnings {
  display: grid;
  gap: 7px;
  margin-bottom: 12px;
}

.warning {
  padding: 8px 10px;
  color: #5f3b00;
  background: #fff7df;
  border: 1px solid #ead59e;
  border-radius: 6px;
  font-size: 13px;
}

.metrics-strip {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  margin-bottom: 16px;
  border: 1px solid var(--line);
  border-radius: 8px;
  overflow: hidden;
}

.metrics-strip div {
  min-width: 0;
  padding: 11px 12px;
  border-right: 1px solid var(--line);
}

.metrics-strip div:last-child {
  border-right: 0;
}

.metrics-strip span {
  display: block;
  color: var(--muted);
  font-size: 12px;
  font-weight: 700;
}

.metrics-strip strong {
  display: block;
  margin-top: 4px;
  font-size: 20px;
}

.state-strip,
.summary-grid {
  display: grid;
  gap: 12px;
  margin-bottom: 16px;
}

.state-strip {
  grid-template-columns: repeat(4, minmax(0, 1fr));
}

.state-strip div,
.summary-block {
  min-width: 0;
  padding: 11px 12px;
  background: #fbfcfc;
  border: 1px solid var(--line);
  border-radius: 8px;
}

.state-strip span,
.kv-grid span {
  display: block;
  color: var(--muted);
  font-size: 12px;
  font-weight: 700;
}

.state-strip strong {
  display: block;
  margin-top: 4px;
  font-size: 17px;
}

.summary-grid {
  grid-template-columns: repeat(2, minmax(0, 1fr));
}

.summary-block .block-heading {
  margin-bottom: 10px;
}

.kv-grid {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 8px;
}

.kv-grid div {
  min-width: 0;
  padding: 8px;
  background: var(--panel-soft);
  border-radius: 6px;
}

#energyDecomposition.kv-grid {
  grid-template-columns: repeat(4, minmax(0, 1fr));
}

.kv-grid strong {
  display: block;
  overflow-wrap: anywhere;
  margin-top: 3px;
  font-size: 14px;
}

.table-block {
  margin-bottom: 16px;
}

table {
  width: 100%;
  border-collapse: collapse;
  border: 1px solid var(--line);
  border-radius: 8px;
  overflow: hidden;
}

th,
td {
  padding: 9px 10px;
  text-align: left;
  border-bottom: 1px solid var(--line);
  font-size: 13px;
}

th {
  color: var(--muted);
  background: var(--panel-soft);
  font-size: 12px;
}

tr:last-child td {
  border-bottom: 0;
}

.empty {
  color: var(--muted);
  text-align: center;
}

.chart-grid {
  display: grid;
  grid-template-columns: minmax(0, 1fr) minmax(320px, 0.9fr);
  gap: 16px;
}

.model-notes {
  margin-top: 16px;
  padding-top: 14px;
  border-top: 1px solid var(--line);
}

.current-energy-block {
  margin-top: 16px;
}

.run-energy-block {
  margin-top: 16px;
}

.knowledge-shell {
  width: min(1120px, calc(100vw - 32px));
  margin: 22px auto 48px;
}

.knowledge-content {
  display: grid;
  gap: 18px;
}

.knowledge-hero,
.lesson-section,
.learning-map,
.takeaway {
  min-width: 0;
  padding: 22px;
  background: var(--panel);
  border: 1px solid var(--line);
  border-radius: 8px;
  box-shadow: var(--shadow);
}

.knowledge-hero {
  padding: 28px;
}

.eyebrow {
  margin: 0 0 8px;
  color: var(--accent-strong);
  font-size: 12px;
  font-weight: 900;
  letter-spacing: 0.08em;
  text-transform: uppercase;
}

.knowledge-hero h1 {
  max-width: 920px;
  margin: 0;
  font-size: 34px;
  line-height: 1.15;
}

.knowledge-hero p:last-child {
  max-width: 820px;
  margin: 14px 0 0;
  color: var(--muted);
  font-size: 16px;
}

.learning-map {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: 10px;
  padding: 12px;
}

.learning-map a {
  display: flex;
  align-items: center;
  min-height: 42px;
  padding: 9px 11px;
  color: var(--accent-strong);
  background: var(--panel-soft);
  border: 1px solid var(--line);
  border-radius: 6px;
  font-size: 13px;
  font-weight: 800;
  text-decoration: none;
}

.learning-map a:hover {
  color: #fff;
  background: var(--accent);
}

.lesson-section {
  display: grid;
  gap: 14px;
}

.lesson-section h2 {
  margin: 0;
  font-size: 22px;
}

.lesson-section p {
  margin: 0;
  color: #2c3c38;
}

.math-block {
  overflow-x: auto;
  padding: 12px 14px;
  color: #17312c;
  background: #fbfcfc;
  border: 1px solid var(--line);
  border-radius: 8px;
}

.math-block mjx-container {
  margin: 0 !important;
}

.explain-grid {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 12px;
}

.explain-grid div,
.note-box {
  min-width: 0;
  padding: 14px;
  background: var(--panel-soft);
  border: 1px solid var(--line);
  border-radius: 8px;
}

.explain-grid strong,
.note-box strong {
  display: block;
  margin-bottom: 6px;
  color: var(--accent-strong);
}

.explain-grid p,
.note-box p {
  color: var(--muted);
  font-size: 13px;
}

.flow-strip {
  display: grid;
  grid-template-columns: minmax(0, 1fr) 24px minmax(0, 1fr) 24px minmax(0, 1fr) 24px minmax(0, 1fr);
  align-items: center;
  gap: 8px;
  padding: 12px;
  background: #fbfcfc;
  border: 1px solid var(--line);
  border-radius: 8px;
}

.flow-strip div {
  min-height: 48px;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 9px;
  color: var(--accent-strong);
  background: var(--accent-soft);
  border-radius: 6px;
  font-size: 13px;
  font-weight: 800;
  text-align: center;
}

.flow-strip svg {
  width: 18px;
  height: 18px;
  color: var(--muted);
  justify-self: center;
}

.compare-table {
  display: grid;
  grid-template-columns: 0.8fr 1fr 1fr;
  overflow: hidden;
  border: 1px solid var(--line);
  border-radius: 8px;
}

.compare-table div {
  min-width: 0;
  padding: 11px 12px;
  border-right: 1px solid var(--line);
  border-bottom: 1px solid var(--line);
  font-size: 13px;
}

.compare-table div:nth-child(3n) {
  border-right: 0;
}

.compare-table div:nth-last-child(-n + 3) {
  border-bottom: 0;
}

.compare-head {
  color: var(--accent-strong);
  background: var(--panel-soft);
  font-weight: 900;
}

.takeaway {
  display: grid;
  gap: 8px;
  background: #f8fbfa;
}

.takeaway h3 {
  color: var(--accent-strong);
  font-size: 17px;
}

.takeaway p {
  margin: 0;
  color: #2c3c38;
}

.formula-grid {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 12px;
}

.formula-card {
  min-width: 0;
  padding: 12px;
  background: var(--panel-soft);
  border: 1px solid var(--line);
  border-radius: 8px;
}

.formula-card h4 {
  margin: 0 0 8px;
  color: var(--accent-strong);
  font-size: 13px;
}

.formula-card code {
  display: block;
  overflow-x: auto;
  padding: 8px;
  color: #17312c;
  background: #fff;
  border: 1px solid #d7e0dc;
  border-radius: 6px;
  font-family: "SFMono-Regular", Consolas, "Liberation Mono", monospace;
  font-size: 12px;
  line-height: 1.5;
  white-space: nowrap;
}

.formula-card p {
  margin: 8px 0 0;
  color: var(--muted);
  font-size: 12px;
  line-height: 1.5;
}

canvas {
  display: block;
  width: 100%;
  height: 300px;
  background: #fbfcfc;
  border: 1px solid var(--line);
  border-radius: 8px;
}

.site-footer {
  text-align: center;
  padding: 24px 16px;
  color: var(--muted);
  font-size: 12px;
}

.site-footer a {
  color: var(--accent-strong);
  text-decoration: none;
}

.site-footer a:hover {
  text-decoration: underline;
}

#heatmapCanvas {
  height: 360px;
}

@media (max-width: 1120px) {
  .workspace,
  .chart-grid,
  .summary-grid,
  .formula-grid,
  .learning-map,
  .explain-grid {
    grid-template-columns: 1fr;
  }

  .control-panel {
    order: 1;
  }

  .results-panel {
    order: 2;
  }
}

@media (max-width: 720px) {
  .topbar {
    position: static;
    align-items: flex-start;
    flex-direction: column;
  }

  .topbar-actions {
    align-items: stretch;
    flex-direction: column;
    width: 100%;
  }

  .nav-link {
    width: 100%;
  }

  .language-switch {
    align-self: stretch;
  }

  .language-switch button {
    flex: 1 1 0;
  }

  .workspace {
    width: min(100vw - 20px, 640px);
    margin-top: 10px;
  }

  .knowledge-shell {
    width: min(100vw - 20px, 640px);
    margin-top: 10px;
  }

  .knowledge-hero,
  .lesson-section,
  .takeaway {
    padding: 16px;
  }

  .knowledge-hero h1 {
    font-size: 25px;
  }

  .toolbar-row,
  .run-row {
    align-items: stretch;
    flex-direction: column;
  }

  .field.short {
    width: auto;
  }

  .two-column,
  .metrics-strip,
  .state-strip,
  .kv-grid,
  .compare-table {
    grid-template-columns: 1fr;
  }

  .compare-table div,
  .compare-table div:nth-child(3n),
  .compare-table div:nth-last-child(-n + 3) {
    border-right: 0;
    border-bottom: 1px solid var(--line);
  }

  .compare-table div:last-child {
    border-bottom: 0;
  }

  .flow-strip {
    grid-template-columns: 1fr;
  }

  .flow-strip svg {
    transform: rotate(90deg);
  }

  .metrics-strip div {
    border-right: 0;
    border-bottom: 1px solid var(--line);
  }

  .metrics-strip div:last-child {
    border-bottom: 0;
  }
}