/* Shared navigation — Nano Genetics / chapter 03 */
.site-header{--nav-ink:#edf1e9;--nav-muted:#abc2ba;--nav-accent:#dcfa87;--nav-line:#35524b;position:relative;z-index:30;display:flex;align-items:center;gap:28px;width:min(1320px,90%);min-height:104px;margin:0 auto;padding:18px 0;border-bottom:1px solid var(--nav-line);color:var(--nav-ink);box-sizing:border-box}
.site-header *, .site-header *::before,.site-header *::after{box-sizing:border-box}
.site-header a{text-decoration:none;color:inherit}
.site-header .site-brand{display:flex;align-items:center;flex-shrink:0;gap:13px;font:500 11px/1.7 Arial,sans-serif;letter-spacing:1.65px}
.site-header .site-brand img{display:block;width:84px;height:56px;object-fit:cover;border-radius:5px}
.site-header .site-brand small{display:block;margin-top:2px;font:9px/1.5 ui-monospace,SFMono-Regular,Consolas,monospace;letter-spacing:2.4px;color:var(--nav-muted)}
.site-header .site-navigation{display:flex;align-items:center;gap:22px;min-width:0;margin-left:auto;font:13px/1.5 Arial,sans-serif}
.site-header .site-nav-group{padding:0;margin:0;border:0}
.site-header .site-nav-group>summary{display:flex;align-items:center;gap:8px;cursor:pointer;padding:14px 0;list-style:none;user-select:none;white-space:nowrap;font:inherit;color:var(--nav-ink)}
.site-header .site-nav-group>summary::-webkit-details-marker{display:none}
.site-header .site-nav-chevron{display:block;width:5px;height:5px;border-right:1px solid currentColor;border-bottom:1px solid currentColor;transform:rotate(45deg);margin-top:-3px;opacity:.7;transition:transform .16s}
.site-header .site-nav-group[open]>summary{color:var(--nav-accent)}
.site-header .site-nav-group[open] .site-nav-chevron{transform:rotate(225deg);margin-top:2px}
.site-header .site-nav-panel{position:absolute;top:calc(100% - 1px);right:0;width:min(480px,100%);display:grid;grid-template-columns:1fr;padding:24px;border:1px solid #49685b;border-radius:0 0 12px 12px;background:linear-gradient(135deg,#15372e,#0b211d 75%);box-shadow:0 24px 52px #03100ee6;max-height:calc(100dvh - 120px);overflow:auto}
.site-header .site-nav-panel-wide{width:min(960px,100%);grid-template-columns:1fr 1fr;gap:24px;padding:28px}
.site-header .site-nav-group:not([open])>.site-nav-panel{display:none}
.site-header .site-nav-column{min-width:0}
.site-header .site-nav-kicker{margin:0 8px 15px;font:10px/1.6 ui-monospace,SFMono-Regular,Consolas,monospace;letter-spacing:1.65px;color:var(--nav-accent)}
.site-header .site-nav-item{display:grid;grid-template-columns:27px minmax(0,1fr) 12px;align-items:start;gap:12px;padding:13px 8px;border-top:1px solid #59766838;border-radius:3px;transition:background .15s}
.site-header .site-nav-item:hover,.site-header .site-nav-item:focus-visible{background:#ceeab10c}
.site-header .site-nav-item strong{display:block;font-size:14px;line-height:1.4;font-weight:400;letter-spacing:0}
.site-header .site-nav-item small{display:block;font-size:11px;line-height:1.5;color:var(--nav-muted);margin-top:4px;letter-spacing:0}
.site-header .site-nav-index{font:10px/1.8 ui-monospace,SFMono-Regular,Consolas,monospace;color:#8cb59c}
.site-header .site-nav-arrow{color:var(--nav-accent);font-size:13px;line-height:1.4;align-self:center}
.site-header .site-nav-support{display:flex;align-items:center;gap:16px;padding:11px 15px;white-space:nowrap;border:1px solid #769055;border-radius:5px;background:#a4d5790a;color:var(--nav-accent);font:12px/1.4 Arial,sans-serif}
.site-header .site-nav-support:hover{background:#d6ee9a12;border-color:var(--nav-accent)}
.site-header .site-language{display:block;flex-shrink:0;margin:0;padding:10px 13px;border:1px solid var(--nav-line);border-radius:30px;background:transparent;color:var(--nav-ink);white-space:nowrap;font:12px/1.4 Arial,sans-serif;cursor:pointer}
.site-header .site-language span{margin-left:5px}
.site-header .site-menu-toggle{display:none}
.site-header :where(a,button,summary):focus-visible{outline:2px solid var(--nav-accent);outline-offset:4px}
.site-header [aria-current="page"]{color:var(--nav-accent)}
@media(max-width:1160px){
 .site-header{gap:18px;flex-wrap:wrap;padding:14px 0;min-height:84px}
 .site-header .site-brand{margin-right:auto}
 .site-header .site-brand img{width:75px;height:50px}
 .site-header .site-navigation{display:flex;order:4;flex-direction:column;align-items:stretch;gap:0;width:100%;margin:0;padding:10px 0 5px;border-top:1px solid var(--nav-line);font-size:15px}
 .site-header[data-nav-ready] .site-navigation{display:none}
 .site-header[data-menu-open] .site-navigation{display:flex}
 .site-header[data-nav-ready] .site-menu-toggle{display:flex;align-items:center;gap:12px;flex-shrink:0;margin:0;padding:10px 12px;background:transparent;border:1px solid var(--nav-line);border-radius:5px;color:var(--nav-ink);font:12px/1.4 Arial,sans-serif;cursor:pointer}
 .site-header .site-menu-icon{width:13px;height:9px;position:relative;display:block;border-top:1px solid currentColor;border-bottom:1px solid currentColor;transition:border-color .15s}
 .site-header .site-menu-icon::before,.site-header .site-menu-icon::after{content:"";position:absolute;left:0;top:3px;width:13px;border-top:1px solid currentColor;transition:transform .15s}
 .site-header[data-menu-open] .site-menu-icon{border-color:transparent}
 .site-header[data-menu-open] .site-menu-icon::before{transform:rotate(45deg)}
 .site-header[data-menu-open] .site-menu-icon::after{transform:rotate(-45deg)}
 .site-header .site-nav-group{border-bottom:1px solid #35524b80}
 .site-header .site-nav-group>summary{justify-content:space-between;padding:18px 3px}
 .site-header .site-nav-panel{position:static;width:100%;max-height:none;overflow:visible;border:0;border-top:1px solid #35524b80;border-radius:6px;background:#102c26;box-shadow:none;padding:20px 14px;margin-bottom:12px}
 .site-header .site-nav-panel-wide{grid-template-columns:1fr 1fr;gap:22px}
 .site-header .site-nav-support{justify-content:space-between;margin:18px 0 4px;padding:14px;font-size:13px}
 .site-header .site-language{padding:10px 12px}
}
@media(max-width:620px){
 .site-header{gap:10px;width:90%}
 .site-header .site-brand{gap:9px;font-size:10px;letter-spacing:1px}
 .site-header .site-brand small{font-size:8px;letter-spacing:1.8px}
 .site-header .site-nav-panel-wide{grid-template-columns:1fr;gap:28px}
 .site-header .site-nav-item{gap:8px;padding:12px 4px;grid-template-columns:23px minmax(0,1fr) 12px}
 .site-header .site-nav-item strong{font-size:14px}
 .site-header .site-nav-item small{font-size:11px}
 .site-header .site-nav-kicker{margin-left:4px}
}
@media(max-width:440px){.site-header .site-brand>span{display:none}.site-header .site-brand img{width:81px;height:54px}.site-header{min-height:82px}}
@media(prefers-reduced-motion:reduce){.site-header *,.site-header *::before,.site-header *::after{transition:none!important}}