.formula-gear {
  --gear-ink: #14344a;
  --gear-muted: #5d7182;
  --gear-line: #d8e2e8;
  --gear-panel: #ffffff;
  --gear-soft: linear-gradient(180deg, #f9fcfe 0%, #eef5f8 100%);
  --gear-accent: #0d6c8b;
  --gear-accent-strong: #0a4f66;
}

.gear-intro-section {
  padding: 28px 0 0;
}

.gear-intro-card {
  display: grid;
  grid-template-columns: minmax(0, 1fr) 280px;
  gap: 24px;
  padding: 28px 32px;
  border: 1px solid var(--gear-line);
  border-radius: 24px;
  background: var(--gear-soft);
}

.gear-kicker {
  margin: 0 0 10px;
  font-size: 12px;
  font-weight: 700;
  text-transform: uppercase;
  color: var(--gear-accent);
}

.gear-intro-card h2 {
  margin: 0 0 12px;
  font-size: 22px;
  line-height: 1.12;
  color: var(--gear-ink);
}

.gear-intro-card p {
  margin: 0;
  font-size: 15px;
  line-height: 1.75;
  color: var(--gear-muted);
}

.gear-intro-note {
  display: flex;
  flex-direction: column;
  gap: 8px;
  padding: 18px 20px;
  border-radius: 18px;
  background: rgba(255, 255, 255, 0.86);
  border: 1px solid rgba(13, 108, 139, 0.12);
}

.gear-main-section {
  padding: 28px 0 60px;
}

.gear-tab-nav {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-bottom: 24px;
}

.gear-tab-btn {
  padding: 12px 18px;
  border: 1px solid var(--gear-line);
  border-radius: 999px;
  background: #fff;
  color: var(--gear-ink);
  font-size: 14px;
  font-weight: 600;
  cursor: pointer;
  transition:
    transform 0.18s ease,
    background 0.18s ease,
    color 0.18s ease,
    border-color 0.18s ease;
}

.gear-tab-btn:hover,
.gear-tab-btn:focus-visible {
  transform: translateY(-1px);
  border-color: var(--gear-accent);
  outline: none;
}

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

.gear-tab-panel {
  padding: 28px;
  border: 1px solid var(--gear-line);
  border-radius: 24px;
  background: var(--gear-panel);
  box-shadow: 0 18px 40px rgba(16, 53, 76, 0.06);
}

.gear-hero {
  display: grid;
  grid-template-columns: minmax(0, 1fr) 340px;
  gap: 24px;
  align-items: center;
  margin-bottom: 24px;
}

.gear-hero h3 {
  margin: 0 0 12px;
  font-size: 20px;
  line-height: 1.2;
  color: var(--gear-ink);
}

.gear-hero p {
  margin: 0;
  font-size: 15px;
  line-height: 1.75;
  color: var(--gear-muted);
}

.gear-figure {
  margin: 0;
  padding: 16px;
  border-radius: 20px;
  background: #f7fafc;
  border: 1px solid #e3ebf1;
}

.gear-figure img {
  display: block;
  width: 100%;
  height: auto;
  border-radius: 14px;
}

.gear-figure-empty {
  display: flex;
  align-items: center;
  justify-content: center;
  min-height: 180px;
  padding: 20px;
  border: 1px dashed #bfd0db;
  border-radius: 14px;
  background: #fff;
  font-size: 14px;
  line-height: 1.6;
  text-align: center;
  color: var(--gear-muted);
}

.gear-table-grid {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 20px;
  align-items: start;
}

.gear-card {
  padding: 20px;
  border-radius: 20px;
  background: #f9fbfc;
  border: 1px solid #e6edf2;
}

.gear-card-head {
  display: flex;
  justify-content: space-between;
  align-items: flex-start;
  gap: 16px;
  margin-bottom: 14px;
}

.gear-card-head h4 {
  margin: 0;
  font-size: 17px;
  color: var(--gear-ink);
}

.gear-card-formulas {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  justify-content: flex-end;
}

.gear-math-inline {
  padding: 8px 10px;
  border-radius: 12px;
  background: #fff;
  color: var(--gear-accent-strong);
}

.gear-table {
  width: 100%;
  border-collapse: collapse;
}

.gear-table tr + tr td {
  border-top: 1px solid #e1e9ef;
}

.gear-table td {
  padding: 12px 10px;
  vertical-align: middle;
  font-size: 14px;
  color: var(--gear-ink);
}

.gear-table td:first-child {
  width: 42%;
  font-weight: 600;
}

.gear-table td:nth-child(2) {
  width: 18%;
  text-align: center;
  color: var(--gear-accent-strong);
}

.gear-table td:nth-child(3) {
  width: 22%;
}

.gear-table td:nth-child(4) {
  width: 18%;
}

.gear-table input,
.gear-table select {
  height: 44px;
  padding: 0 12px;
  border: 1px solid #cfdae3;
  border-radius: 12px;
  background: #fff;
  color: var(--gear-ink);
  font-size: 14px;
}

.gear-table input[disabled] {
  background: #eef4f8;
  color: var(--gear-muted);
}

.gear-error {
  margin: 14px 0 0;
  min-height: 20px;
  font-size: 13px;
  color: #c03d40;
}

@media (max-width: 991px) {
  .gear-intro-card,
  .gear-hero,
  .gear-table-grid {
    grid-template-columns: 1fr;
  }
}

@media (max-width: 767px) {
  .gear-tab-panel {
    padding: 18px;
  }

  .gear-card {
    padding: 16px;
  }

  .gear-card-head {
    flex-direction: column;
  }

  .gear-card-formulas {
    justify-content: flex-start;
  }

  .gear-table,
  .gear-table tbody,
  .gear-table tr,
  .gear-table td {
    display: block;
    width: 100%;
  }

  .gear-table tr {
    padding: 12px 0;
  }

  .gear-table td {
    padding: 6px 0;
    border: 0;
  }

  .gear-table tr + tr {
    border-top: 1px solid #e1e9ef;
  }
}