/* Chapters remain in the page flow; the navigation follows the reading position. */
.field-section{position:relative}.field-heading{padding-bottom:25px}
.field-tabs{position:sticky;top:0;z-index:7;display:flex;align-items:center;gap:32px;margin:0;padding:0 var(--gutter);min-height:70px;background:var(--forest);border-bottom:1px solid var(--dark-rule)}
.field-tabs a{display:flex;align-items:center;min-height:70px;padding:15px 0;border-bottom:2px solid transparent;text-decoration:none;color:var(--light-muted);font-size:14px;white-space:nowrap;transition:color 160ms var(--ease),border-color 160ms var(--ease)}
.field-tabs a[aria-current=location]{color:var(--light);border-color:var(--light)}
.field-panel{padding-top:35px;padding-bottom:75px;scroll-margin-top:80px}
.field-panel+.field-panel{border-top:1px solid var(--dark-rule)}
.field-panel:last-child{padding-bottom:0}
#panel-learn figure>img{height:auto;aspect-ratio:1672/941;object-fit:contain}
@media(max-width:760px){.field-heading{padding-bottom:18px}.field-tabs{gap:22px;min-height:60px;padding:0 22px}.field-tabs a{font-size:12px;min-height:60px;padding:13px 0}.field-panel{padding-top:25px;padding-bottom:50px;scroll-margin-top:70px}}
@media(max-width:350px){.field-tabs{gap:16px}.field-tabs a{font-size:11px}}
@media(prefers-reduced-motion:reduce){.field-tabs a{transition:none}}