.section-header{position:sticky;top:0;z-index:100;background:var(--ground,var(--color-bone,#fff));border-bottom:1px solid var(--rule,#e6e2d9)}
.section-header-inner{max-width:1040px;margin:auto;padding:17px 24px;display:grid;grid-template-columns:auto 1fr auto;gap:30px;align-items:center}
.section-brand{display:inline-flex;align-items:center;gap:10px;color:var(--text,#0b0b0c);text-decoration:none;white-space:nowrap;font-family:Arial,sans-serif;font-size:22px;font-weight:750;letter-spacing:-.8px}
.section-brand .brand-mark{width:32px;height:32px;flex:none}.section-brand .brand-lab{font-weight:400}
.section-book{grid-column:3;grid-row:1;display:inline-flex;justify-content:center;align-items:center;gap:12px;min-height:42px;padding:8px 16px;background:var(--accent,#1d2de0);color:var(--accent-ink,#fff)!important;text-decoration:none;font:600 12px Arial,sans-serif;border-radius:2px;white-space:nowrap}
.section-navigation{grid-column:2;grid-row:1;display:flex;justify-content:center;gap:21px;min-width:0}
.section-navigation a{font:600 11px Arial,sans-serif;letter-spacing:.01em;white-space:nowrap;text-decoration:none;color:var(--text-dim,#5b5b63);padding:14px 0;border-bottom:2px solid transparent}
.section-navigation a:hover,.section-navigation a[aria-current=location]{color:var(--accent,#1d2de0);border-color:var(--accent,#1d2de0)}
.section-header a:focus-visible{outline:2px solid var(--accent,#1d2de0);outline-offset:3px}
@media(max-width:860px){.section-header-inner{grid-template-columns:1fr auto;gap:4px 16px;padding-top:12px;padding-bottom:0}.section-book{grid-column:2}.section-navigation{grid-column:1/-1;grid-row:2;justify-content:space-between;gap:14px;overflow-x:auto;scrollbar-width:thin;overscroll-behavior-x:contain;padding-bottom:2px}.section-navigation a{font-size:11px;flex:none}.section-brand{font-size:20px}}
@media(max-width:380px){.section-header-inner{padding-inline:16px}.section-navigation{gap:11px}.section-navigation a{font-size:10px}.section-brand{font-size:18px}.section-book{padding-inline:12px;min-height:38px}}
@media(prefers-reduced-motion:no-preference){html{scroll-behavior:smooth}}
:target{scroll-margin-top:140px}