:root {
  --bg: #f6efe4;
  --bg-strong: #efe1cf;
  --paper: rgba(255, 252, 246, 0.85);
  --paper-strong: rgba(255, 249, 240, 0.95);
  --panel-border: rgba(111, 80, 53, 0.18);
  --ink: #2c2019;
  --muted: #715d50;
  --accent: #0f766e;
  --accent-soft: rgba(15, 118, 110, 0.12);
  --accent-warm: #b45309;
  --accent-warm-soft: rgba(180, 83, 9, 0.12);
  --shadow: 0 18px 40px rgba(69, 45, 28, 0.14);
  --radius-xl: 28px;
  --radius-lg: 18px;
  --radius-md: 12px;
}

* {
  box-sizing: border-box;
}

body {
  margin: 0;
  min-height: 100vh;
  font-family: "LXGW WenKai", "LXGW WenKai Screen", "KaiTi", serif;
  font-weight: 500;
  color: var(--ink);
  background:
    radial-gradient(circle at top right, rgba(180, 83, 9, 0.18), transparent 28%),
    radial-gradient(circle at bottom left, rgba(15, 118, 110, 0.14), transparent 35%),
    linear-gradient(135deg, #fbf6ee 0%, var(--bg) 48%, var(--bg-strong) 100%);
}

body::before {
  content: "";
  position: fixed;
  inset: 0;
  pointer-events: none;
  opacity: 0.08;
  background-image: linear-gradient(rgba(44, 32, 25, 0.35) 1px, transparent 1px), linear-gradient(90deg, rgba(44, 32, 25, 0.35) 1px, transparent 1px);
  background-size: 36px 36px;
}

.page-shell {
  width: min(1240px, calc(100% - 32px));
  margin: 0 auto;
  padding: 32px 0 48px;
}

.hero {
  display: grid;
  grid-template-columns: 1.6fr 0.9fr;
  gap: 20px;
  margin-bottom: 24px;
}

.hero-copy,
.hero-card,
.panel {
  border: 1px solid var(--panel-border);
  background: var(--paper);
  backdrop-filter: blur(12px);
  border-radius: var(--radius-xl);
  box-shadow: var(--shadow);
}

.hero-copy {
  padding: 28px;
}

.eyebrow,
.section-tag {
  margin: 0 0 8px;
  font-size: 0.86rem;
  letter-spacing: 0.18em;
  text-transform: uppercase;
  color: var(--accent);
}

h1,
h2,
h3,
th {
  font-family: "LXGW WenKai", "LXGW WenKai Screen", "KaiTi", serif;
  font-weight: 700;
}

h1 {
  margin: 0;
  font-size: clamp(2.2rem, 5vw, 4.25rem);
  line-height: 0.98;
}

.hero-text {
  max-width: 60ch;
  margin: 16px 0 0;
  color: var(--muted);
  line-height: 1.7;
  font-size: 1.12rem;
}

.hero-meta {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  margin-top: 18px;
}

.hero-badge,
.status-badge {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 8px 12px;
  border-radius: 999px;
  background: rgba(15, 118, 110, 0.12);
  color: var(--accent);
  font-size: 0.94rem;
}

.hero-badge.warm,
.status-badge {
  background: var(--accent-warm-soft);
  color: var(--accent-warm);
}

.hero-card {
  padding: 22px 24px;
  align-self: end;
  background: linear-gradient(180deg, rgba(255, 252, 246, 0.92), rgba(242, 231, 216, 0.92));
}

.hero-card p {
  margin: 0 0 12px;
  font-weight: 700;
}

.hero-card ul {
  margin: 0;
  padding-left: 18px;
  color: var(--muted);
  line-height: 1.7;
}

.layout-grid {
  display: grid;
  grid-template-columns: 1.2fr 1fr;
  gap: 20px;
}

.panel {
  padding: 24px;
}

.formula-panel {
  grid-column: 1 / -1;
}

.panel-heading {
  display: flex;
  justify-content: space-between;
  align-items: flex-start;
  gap: 16px;
  margin-bottom: 20px;
}

.panel-heading.compact {
  margin-bottom: 16px;
}

.panel-heading h2,
.result-block h3,
.formula-card h3 {
  margin: 0;
}

.badge-stack {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
}

.status-badge.ready {
  background: rgba(15, 118, 110, 0.12);
  color: var(--accent);
}

.instrument-grid {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 14px;
  margin-bottom: 18px;
}

.field-card {
  display: flex;
  flex-direction: column;
  gap: 8px;
  padding: 14px;
  border-radius: var(--radius-lg);
  background: rgba(255, 255, 255, 0.62);
  border: 1px solid rgba(111, 80, 53, 0.12);
}

.field-card span {
  font-size: 0.98rem;
  color: var(--muted);
}

input {
  width: 100%;
  border: 1px solid rgba(111, 80, 53, 0.2);
  background: rgba(255, 255, 255, 0.8);
  border-radius: 10px;
  padding: 12px 14px;
  font-size: 1.06rem;
  font-family: "LXGW WenKai", "LXGW WenKai Screen", "KaiTi", serif;
  color: var(--ink);
}

input:focus {
  outline: 2px solid rgba(15, 118, 110, 0.25);
  border-color: rgba(15, 118, 110, 0.55);
}

.table-wrap {
  overflow-x: auto;
}

table {
  width: 100%;
  border-collapse: collapse;
  border-radius: var(--radius-lg);
  overflow: hidden;
  background: rgba(255, 255, 255, 0.72);
}

th,
td {
  padding: 12px;
  text-align: left;
  border-bottom: 1px solid rgba(111, 80, 53, 0.12);
}

thead th {
  background: rgba(44, 32, 25, 0.06);
  font-size: 1.06rem;
}

tbody td {
  font-size: 1.02rem;
}

tbody tr:last-child td {
  border-bottom: none;
}

.actions {
  display: flex;
  gap: 12px;
  margin-top: 18px;
}

button {
  cursor: pointer;
  border: none;
  border-radius: 999px;
  padding: 12px 18px;
  font-size: 1.02rem;
  font-family: "LXGW WenKai", "LXGW WenKai Screen", "KaiTi", serif;
  font-weight: 700;
  transition: transform 180ms ease, box-shadow 180ms ease, background 180ms ease;
}

button:hover {
  transform: translateY(-1px);
}

.primary-button {
  color: #fffdf9;
  background: linear-gradient(135deg, var(--accent), #0b5f59);
  box-shadow: 0 12px 24px rgba(15, 118, 110, 0.22);
}

.ghost-button {
  color: var(--ink);
  background: rgba(255, 255, 255, 0.64);
  border: 1px solid rgba(111, 80, 53, 0.16);
}

.helper-text {
  margin: 12px 0 0;
  color: var(--muted);
  font-size: 1rem;
  line-height: 1.6;
}

.method-note {
  display: grid;
  gap: 6px;
  padding: 14px 16px;
  margin-bottom: 16px;
  border-radius: var(--radius-lg);
  background: linear-gradient(135deg, rgba(15, 118, 110, 0.08), rgba(255, 255, 255, 0.75));
  border: 1px solid rgba(15, 118, 110, 0.18);
  color: var(--muted);
  font-size: 1rem;
}

.method-note strong {
  color: var(--ink);
}

.stat-grid,
.detail-grid,
.formula-grid {
  display: grid;
  gap: 14px;
}

.stat-grid {
  grid-template-columns: repeat(2, minmax(0, 1fr));
  margin-bottom: 16px;
}

.stat-card,
.detail-card,
.result-list .result-item,
.formula-card {
  border-radius: var(--radius-lg);
  border: 1px solid rgba(111, 80, 53, 0.12);
  background: rgba(255, 255, 255, 0.68);
}

.stat-card,
.detail-card,
.result-item {
  padding: 14px;
}

.stat-card p,
.detail-card p,
.formula-card p,
.result-item p {
  margin: 0;
}

.stat-card .label,
.detail-card .label,
.result-item .label {
  color: var(--muted);
  font-size: 0.96rem;
  margin-bottom: 8px;
  line-height: 1.5;
}

.stat-card .value,
.detail-card .value,
.result-item .value {
  font-size: 1.16rem;
  font-weight: 700;
  word-break: break-word;
  line-height: 1.55;
}

.math-label-only {
  display: flex;
  align-items: center;
  min-height: 1.5em;
}

.math-render.math-inline {
  display: inline-flex;
  align-items: center;
}

.label .math-render.math-inline {
  margin-left: 0.18rem;
}

.result-block + .result-block {
  margin-top: 16px;
}

.detail-block {
  overflow: hidden;
  border-radius: var(--radius-lg);
  border: 1px solid rgba(111, 80, 53, 0.12);
  background: rgba(255, 255, 255, 0.58);
}

.detail-summary {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 12px;
  padding: 16px 18px;
  cursor: pointer;
  user-select: none;
  list-style: none;
  background: linear-gradient(135deg, rgba(255, 255, 255, 0.86), rgba(15, 118, 110, 0.08));
}

.detail-summary::-webkit-details-marker {
  display: none;
}

.detail-summary::after {
  content: "展开";
  flex-shrink: 0;
  padding: 6px 10px;
  border-radius: 999px;
  background: rgba(15, 118, 110, 0.12);
  color: var(--accent);
  font-size: 0.88rem;
  font-weight: 700;
}

.detail-block[open] .detail-summary {
  border-bottom: 1px solid rgba(111, 80, 53, 0.12);
}

.detail-block[open] .detail-summary::after {
  content: "收起";
  background: rgba(180, 83, 9, 0.12);
  color: var(--accent-warm);
}

.detail-panel {
  padding: 16px 0 0;
}

.result-list,
.detail-grid {
  min-height: 84px;
}

.result-list {
  display: grid;
  gap: 12px;
}

.result-item .subtext {
  margin-top: 8px;
  color: var(--muted);
  font-size: 0.96rem;
  line-height: 1.6;
}

.result-primary {
  margin-top: 10px;
  padding: 14px 16px;
  border-radius: 16px;
  background: linear-gradient(135deg, rgba(255, 255, 255, 0.92), rgba(15, 118, 110, 0.08));
  border: 1px solid rgba(15, 118, 110, 0.15);
}

.result-primary .katex-display {
  font-size: 1.12em;
}

.result-overview {
  margin-top: 12px;
}

.result-overview-label {
  color: var(--muted);
}

.result-overview-value {
  font-weight: 650;
  color: var(--ink);
}

.final-expression {
  color: var(--ink);
}

.final-expression-label {
  color: var(--muted);
}

.final-expression-value {
  font-weight: 800;
  color: var(--ink);
}

.empty-state {
  display: grid;
  place-items: center;
  text-align: center;
  color: var(--muted);
  border-radius: var(--radius-lg);
  background: rgba(255, 255, 255, 0.45);
  border: 1px dashed rgba(111, 80, 53, 0.2);
  padding: 24px;
}

.formula-grid {
  grid-template-columns: repeat(3, minmax(0, 1fr));
}

.formula-card {
  display: grid;
  gap: 14px;
  padding: 18px;
  background: linear-gradient(180deg, rgba(255, 255, 255, 0.74), var(--paper-strong));
}

.formula-card.emphasis {
  border-color: rgba(15, 118, 110, 0.24);
  box-shadow: inset 0 0 0 1px rgba(15, 118, 110, 0.08);
}

.formula-card-head {
  display: flex;
  align-items: center;
  gap: 12px;
}

.formula-index {
  min-width: 38px;
  height: 38px;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  border-radius: 50%;
  background: rgba(44, 32, 25, 0.08);
  color: var(--ink);
  font-weight: 700;
}

.formula-line {
  min-height: 66px;
  display: grid;
  align-items: center;
  padding: 14px;
  border-radius: 16px;
  background: rgba(255, 255, 255, 0.84);
  border: 1px solid rgba(111, 80, 53, 0.12);
}

.formula-line.rendered {
  background: linear-gradient(135deg, rgba(255, 255, 255, 0.92), rgba(15, 118, 110, 0.06));
}

.formula-fallback {
  font-family: "LXGW WenKai Mono", "LXGW WenKai", monospace;
  font-size: 0.96rem;
  color: #7c2d12;
  white-space: normal;
}

code,
pre {
  font-family: "LXGW WenKai Mono", "LXGW WenKai", monospace;
}

.formula-note {
  padding: 12px 14px;
  border-radius: 14px;
  background: rgba(180, 83, 9, 0.08);
  color: var(--muted);
  line-height: 1.6;
}

.katex-display {
  margin: 0;
  overflow-x: auto;
  overflow-y: hidden;
}

.katex {
  font-size: 1.05em;
}

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

  .formula-grid {
    grid-template-columns: 1fr;
  }
}

@media (max-width: 860px) {
  .instrument-grid,
  .stat-grid {
    grid-template-columns: 1fr;
  }
}

@media (max-width: 640px) {
  .page-shell {
    width: min(100% - 20px, 100%);
    padding-top: 18px;
  }

  .hero-copy,
  .hero-card,
  .panel {
    border-radius: 22px;
  }

  .panel,
  .hero-copy,
  .hero-card {
    padding: 18px;
  }

  .actions,
  .hero-meta {
    flex-direction: column;
  }
}