/* Keep all four navigation destinations available on small screens. */
@media(max-width:700px){
 .header{height:auto;min-height:76px;padding:12px 5% 8px;flex-wrap:wrap;gap:8px}
 .header .brand{font-size:30px;gap:9px}
 .header .brand>span{font-size:13px}
 .header .brand small{font-size:9px;margin-top:4px}
 .header nav{display:grid;grid-template-columns:repeat(4,minmax(0,1fr));width:100%;gap:6px;font-size:12px}
 .header nav a,.header nav a:nth-child(3),.header nav .nav-about{display:flex;align-items:center;justify-content:center;min-width:0;min-height:40px;padding:6px 2px;white-space:nowrap}
 .header nav .nav-about{border:1.5px solid var(--ink);box-shadow:2px 2px 0 var(--ink)}
 .header nav .nav-about span{display:none}
}
.section-rail{position:fixed;right:max(12px,env(safe-area-inset-right));top:50%;transform:translateY(-50%);z-index:45;display:flex;flex-direction:column;align-items:center;gap:4px;pointer-events:none}
.section-rail button{display:grid;place-items:center;width:28px;height:38px;padding:0;border:0;background:none;cursor:pointer;pointer-events:auto;touch-action:manipulation}
.section-rail button span{display:block;width:10px;height:10px;border:1px solid #000;border-radius:99px;background:rgba(255,255,255,.55);box-shadow:3px 3px 0 #000;transition:height .25s ease,background-color .25s ease}
.section-rail button[aria-current] span{height:30px;background:#fff}
.section-rail button:focus-visible{outline:2px solid #000;outline-offset:1px;border-radius:8px;background:#ffffff40}
.section-rail button:hover span{background:#fff}
@media(max-width:700px){.section-rail{right:max(0px,env(safe-area-inset-right));gap:0}.section-rail button{width:30px;height:36px}.section-rail button span{width:8px;height:8px;box-shadow:2px 3px 0 #000}.section-rail button[aria-current] span{height:26px}}
@media(prefers-reduced-motion:reduce){.section-rail button span{transition:none}}