.feature-browser {
  display: grid;
  grid-template-columns: minmax(250px, 0.75fr) minmax(0, 1.5fr);
  gap: 18px;
  align-items: stretch;
}

.feature-tabs {
  display: grid;
  gap: 8px;
  align-content: start;
}

.feature-tab {
  display: grid;
  width: 100%;
  min-height: 86px;
  grid-template-columns: 36px minmax(0, 1fr);
  gap: 12px;
  padding: 15px;
  border: 1px solid var(--color-border);
  border-radius: var(--radius-lg);
  background: var(--color-panel);
  color: var(--color-text-muted);
  cursor: pointer;
  text-align: left;
  transition: color var(--transition-fast), border-color var(--transition-fast), background-color var(--transition-fast);
}

.feature-tab:hover {
  border-color: var(--color-accent);
  color: var(--color-text);
}

.feature-tab[aria-selected="true"],
.feature-tab.is-active {
  border-color: transparent;
  background: linear-gradient(var(--color-panel-raised), var(--color-panel-raised)) padding-box, var(--gradient-accent-soft) border-box;
  color: var(--color-text);
}

.feature-tab-icon {
  display: flex;
  width: 36px;
  height: 36px;
  flex-shrink: 0;
  align-items: center;
  justify-content: center;
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  color: var(--color-accent);
}

.feature-tab-icon svg {
  width: 18px;
  height: 18px;
}

.feature-tab-copy {
  display: grid;
  gap: 3px;
}

.feature-tab-title {
  color: var(--color-text);
  font-family: var(--font-display);
  font-size: 15px;
  font-weight: 500;
}

.feature-tab-summary {
  color: var(--color-text-muted);
  font-size: 12.5px;
  line-height: 1.55;
}

.tab-panels {
  min-width: 0;
}

.tab-panel {
  min-height: 100%;
  padding: 40px;
  border: 1px solid var(--color-border);
  border-radius: var(--radius-xl);
  background: var(--color-panel-raised);
  color: var(--color-text-muted);
}

.tab-panel[hidden] {
  display: none;
}

.tab-panel h3 {
  color: var(--color-text);
}

.parameter-line {
  margin-top: 28px;
  padding-top: 18px;
  border-top: 1px solid var(--color-border);
  color: var(--color-text-muted);
  font-family: var(--font-mono);
  font-size: 12px;
  overflow-wrap: anywhere;
}

.toc-tabs {
  position: sticky;
  top: 12px;
  z-index: 10;
  display: flex;
  max-width: 100%;
  margin-bottom: 44px;
  padding: 8px;
  gap: 7px;
  overflow-x: auto;
  border: 1px solid var(--color-border);
  border-radius: var(--radius-pill);
  background: var(--color-panel);
  color: var(--color-text);
  -webkit-overflow-scrolling: touch;
}

.toc-tabs a {
  display: inline-flex;
  min-height: 38px;
  flex: 0 0 auto;
  align-items: center;
  padding: 6px 14px;
  border-radius: var(--radius-pill);
  color: var(--color-text-muted);
  font-family: var(--font-mono);
  font-size: 12px;
}

.toc-tabs a:hover,
.toc-tabs a[aria-current="location"] {
  background: var(--color-panel-raised);
  color: var(--color-accent);
}

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

.faq-item {
  overflow: clip;
  border: 1px solid var(--color-border);
  border-radius: var(--radius-lg);
  background: var(--color-panel);
  color: var(--color-text);
}

.faq-item[open] {
  border-color: var(--color-accent);
}

.faq-item summary {
  display: flex;
  min-height: 64px;
  align-items: center;
  justify-content: space-between;
  gap: 18px;
  padding: 17px 20px;
  color: var(--color-text);
  cursor: pointer;
  font-family: var(--font-display);
  font-size: 16px;
  font-weight: 500;
  list-style: none;
}

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

.faq-item summary::after {
  width: 9px;
  height: 9px;
  flex-shrink: 0;
  border-right: 1.5px solid var(--color-accent);
  border-bottom: 1.5px solid var(--color-accent);
  content: "";
  transform: rotate(45deg);
  transition: transform var(--transition-fast);
}

.faq-item[open] summary::after {
  transform: rotate(225deg);
}

.faq-answer {
  padding: 0 20px 20px;
  border-top: 1px solid var(--color-border);
  color: var(--color-text-muted);
}

.faq-answer p:first-child {
  margin-top: 16px;
}

.glossary-grid {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 14px;
}

.term-card {
  position: relative;
  padding: 24px;
  overflow: clip;
  border: 1px solid var(--color-border);
  border-radius: var(--radius-lg);
  background: var(--color-panel);
  color: var(--color-text-muted);
}

.term-card::before {
  position: absolute;
  top: 0;
  bottom: 0;
  left: 0;
  width: 3px;
  background: var(--gradient-accent);
  content: "";
}

.term-code {
  margin-bottom: 9px;
  color: var(--color-accent);
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.1em;
}

.term-card h3 {
  margin-bottom: 8px;
  color: var(--color-text);
  font-size: 20px;
}

.term-card p:last-child {
  margin-bottom: 0;
}

.client-grid {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 16px;
}

.client-card {
  display: flex;
  min-width: 0;
  flex-direction: column;
  padding: 25px;
  border: 1px solid var(--color-border);
  border-radius: var(--radius-xl);
  background: var(--color-panel);
  color: var(--color-text-muted);
}

.client-card.is-primary {
  border-color: transparent;
  background: linear-gradient(var(--color-panel-raised), var(--color-panel-raised)) padding-box, var(--gradient-accent-soft) border-box;
}

.client-head {
  display: flex;
  align-items: flex-start;
  gap: 15px;
}

.client-icon {
  width: 52px;
  height: 52px;
  flex-shrink: 0;
}

.client-title {
  flex: 1;
  min-width: 0;
}

.client-title h3 {
  margin-bottom: 5px;
  color: var(--color-text);
  font-size: 20px;
}

.client-meta {
  min-height: 20px;
  color: var(--color-text-muted);
  font-family: var(--font-mono);
  font-size: 11.5px;
}

.client-version:empty {
  display: none;
}

.client-body {
  flex: 1;
  margin-top: 18px;
}

.client-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  margin-top: 20px;
}

.client-badges {
  display: flex;
  flex-wrap: wrap;
  gap: 7px;
  margin-top: 12px;
}

.client-badge {
  display: inline-flex;
  max-width: 100%;
  min-height: 26px;
  align-items: center;
  padding: 3px 10px;
  overflow: hidden;
  border: 1px solid var(--color-border);
  border-radius: var(--radius-pill);
  color: var(--color-text);
  font-family: var(--font-mono);
  font-size: 11px;
}

.client-badge-pick {
  border-color: var(--color-accent);
  background: var(--color-accent-surface);
}

.client-badge-recommend {
  border-color: var(--color-success);
  background: var(--color-success-surface);
}

.client-badge-archived {
  border-color: var(--color-warning);
  background: var(--color-warning-surface);
}

.post-grid {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 16px;
}

.post-card {
  display: flex;
  min-height: 100%;
  flex-direction: column;
  padding: 24px;
  border: 1px solid var(--color-border);
  border-radius: var(--radius-lg);
  background: var(--color-panel);
  color: var(--color-text-muted);
  transition: transform var(--transition-fast), border-color var(--transition-fast), background-color var(--transition-fast);
}

.post-card:hover {
  border-color: var(--color-accent);
  background: var(--color-panel-raised);
  color: var(--color-text-muted);
  transform: translateY(-3px);
}

.post-meta {
  display: flex;
  flex-wrap: wrap;
  gap: 9px;
  margin-bottom: 17px;
  color: var(--color-text-muted);
  font-family: var(--font-mono);
  font-size: 11px;
}

.post-card h3 {
  margin-bottom: 12px;
  color: var(--color-text);
  font-size: 20px;
}

.post-card p {
  flex: 1;
}

.post-link {
  margin-top: 12px;
  color: var(--color-accent);
  font-family: var(--font-mono);
  font-size: 12px;
}

.callout {
  position: relative;
  margin: 28px 0;
  padding: 20px 22px 20px 26px;
  overflow: clip;
  border: 1px solid var(--color-border);
  border-radius: var(--radius-lg);
  background: var(--color-panel-raised);
  color: var(--color-text-muted);
}

.callout::before {
  position: absolute;
  inset-block: 0;
  left: 0;
  width: 4px;
  background: var(--gradient-accent);
  content: "";
}

.callout-title {
  margin-bottom: 7px;
  color: var(--color-text);
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.07em;
}

.callout p:last-child {
  margin-bottom: 0;
}

.callout-success {
  border-color: var(--color-success);
  background: var(--color-success-surface);
}

.callout-warning {
  border-color: var(--color-warning);
  background: var(--color-warning-surface);
}

.callout-error {
  border-color: var(--color-error);
  background: var(--color-error-surface);
}

.download-prompt {
  display: grid;
  margin-top: 64px;
  grid-template-columns: minmax(0, 1fr) auto;
  gap: 24px;
  align-items: center;
  padding: 28px;
  border: 1px solid var(--color-border);
  border-radius: var(--radius-xl);
  background: var(--gradient-panel);
  color: var(--color-text);
}

.download-prompt h2,
.download-prompt h3 {
  margin-bottom: 8px;
}

.download-prompt p {
  margin-bottom: 0;
  color: var(--color-text-muted);
}

.download-prompt-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
}

.dl-fab {
  position: fixed;
  right: 22px;
  bottom: 22px;
  z-index: 35;
  display: inline-flex;
  min-height: 50px;
  align-items: center;
  gap: 10px;
  padding: 8px 18px 8px 11px;
  border: 1px solid transparent;
  border-radius: var(--radius-pill);
  background: linear-gradient(var(--color-panel-raised), var(--color-panel-raised)) padding-box, var(--gradient-accent-soft) border-box;
  color: var(--color-text);
  box-shadow: 0 16px 42px var(--color-shadow-soft);
  font-family: var(--font-mono);
  font-size: 12.5px;
}

.dl-fab:hover {
  color: var(--color-accent);
}

.dl-fab-icon {
  display: flex;
  width: 34px;
  height: 34px;
  flex-shrink: 0;
  align-items: center;
  justify-content: center;
  border-radius: var(--radius-pill);
  background: var(--gradient-accent);
  color: var(--color-bg);
}

.dl-fab-icon svg {
  width: 17px;
  height: 17px;
}

.prose > .data-table {
  display: block;
  max-width: 100%;
  min-width: 0;
  overflow-x: auto;
  -webkit-overflow-scrolling: touch;
}

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

.swatch {
  overflow: clip;
  border: 1px solid var(--color-border);
  border-radius: var(--radius-lg);
  background: var(--color-panel);
  color: var(--color-text);
}

.swatch-color {
  height: 88px;
  border-bottom: 1px solid var(--color-border);
}

.swatch-copy {
  padding: 13px;
}

.swatch-copy strong,
.swatch-copy code {
  display: block;
}

.swatch-copy code {
  margin-top: 4px;
  color: var(--color-text-muted);
  font-size: 11px;
}

.swatch-bg {
  background: var(--color-bg);
}

.swatch-panel {
  background: var(--color-panel);
}

.swatch-raised {
  background: var(--color-panel-raised);
}

.swatch-border {
  background: var(--color-border);
}

.swatch-accent {
  background: var(--color-accent);
}

.swatch-accent-deep {
  background: var(--color-accent-deep);
}

.swatch-pink {
  background: var(--color-pink);
}

.swatch-text {
  background: var(--color-text);
}

.swatch-muted {
  background: var(--color-text-muted);
}

.swatch-success {
  background: var(--color-success);
}

.swatch-warning {
  background: var(--color-warning);
}

.swatch-error {
  background: var(--color-error);
}

.type-sample {
  padding: 28px 0;
  border-bottom: 1px solid var(--color-border);
}

.type-sample:last-child {
  border-bottom: 0;
}

.type-display {
  color: var(--color-text);
  font-family: var(--font-display);
  font-size: clamp(34px, 4.3vw, 48px);
  font-weight: 400;
  line-height: 1.16;
}

.type-body {
  max-width: 720px;
  color: var(--color-text-muted);
  font-size: 16px;
}

.type-mono {
  color: var(--color-accent);
  font-family: var(--font-mono);
  font-size: 13px;
}

@media (max-width: 900px) {
  .feature-browser {
    grid-template-columns: 1fr;
  }

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

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

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

@media (max-width: 640px) {
  .feature-tabs,
  .glossary-grid,
  .client-grid,
  .post-grid {
    grid-template-columns: 1fr;
  }

  .feature-tab {
    min-height: 76px;
  }

  .tab-panel {
    padding: 25px 20px;
  }

  .toc-tabs {
    top: 8px;
    border-radius: var(--radius-lg);
  }

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

  .download-prompt {
    grid-template-columns: 1fr;
    padding: 22px;
  }

  .download-prompt-actions .btn {
    flex: 1 1 100%;
  }

  .dl-fab {
    right: 16px;
    bottom: 16px;
    max-width: calc(100vw - 32px);
  }
}