/* Accesos principales: una fila en todas las pantallas. */
.site-header{display:flex;flex-direction:column;align-items:center;justify-content:center;gap:12px;width:min(1160px,calc(100% - 32px));padding:14px 0 12px}
.site-header .identity{align-self:center;justify-content:center;gap:10px;font-size:clamp(.82rem,1.7vw,1.05rem);letter-spacing:.055em;line-height:1.12}
.site-header .identity img{width:clamp(48px,6vw,62px);height:clamp(48px,6vw,62px)}
.site-header nav{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:clamp(7px,1.6vw,18px);width:100%;max-width:660px;justify-content:stretch}
.site-header nav a{grid-column:auto;display:flex;align-items:center;justify-content:flex-start;gap:clamp(5px,1vw,14px);min-width:0;min-height:52px;padding:8px clamp(8px,1.5vw,18px);border:1px solid #398bc0;border-radius:12px;background:linear-gradient(135deg,#164b7b,#0b2b4e);box-shadow:inset 0 1px 12px #6ecbff15,0 5px 18px #00112c30;font-size:clamp(.72rem,1.4vw,.9rem);font-weight:800;text-decoration:none;white-space:nowrap;color:#eff9ff;transition:background .18s,border-color .18s,transform .18s}
.site-header nav a:hover{background:linear-gradient(135deg,#1b6093,#103963);border-color:#7fdbff;transform:translateY(-2px)}
.site-header nav a:focus-visible{outline:3px solid #93e4ff;outline-offset:3px}
.site-header .portal-icon{display:flex;align-items:center;justify-content:center;flex-shrink:0;width:clamp(25px,3vw,34px);height:clamp(25px,3vw,34px);border-radius:13px;background:linear-gradient(145deg,#206aa4,#104270);border:1px solid #468cc0;color:#b8e7ff}
.site-header .portal-icon svg{width:65%;height:65%}
.site-header .portal-arrow{margin-left:auto;color:#a9dfff;font-size:1.6rem;line-height:1}
@media(max-width:600px){.site-header{gap:10px;padding:12px 0 10px}.site-header nav a{flex-direction:column;justify-content:center;gap:4px;min-height:60px;padding:6px 4px;border-radius:10px;font-size:clamp(.68rem,2.75vw,.88rem)}.site-header .portal-icon{width:25px;height:25px;border-radius:7px}.site-header .portal-arrow{display:none}}
@media(prefers-reduced-motion:reduce){.site-header nav a{transition:none}}