.site-nav {
    position: fixed;
    top: 30px;
    left: 50%;
    z-index: 99;
    max-width: calc(100vw - 430px);
    transform: translateX(-50%);
}

.site-nav ul {
    display: flex;
    margin: 0;
    padding: 0;
    border: 1px solid var(--line);
    background: color-mix(in srgb, var(--paper) 90%, transparent);
    backdrop-filter: blur(10px);
    list-style: none;
}

.site-nav li + li {
    border-left: 1px solid var(--line);
}

.site-nav a {
    display: block;
    padding: 10px 13px;
    color: var(--ink);
    font-size: 9px;
    line-height: 1;
    letter-spacing: 1px;
    text-decoration: none;
    text-transform: uppercase;
    white-space: nowrap;
}

.site-nav a:hover {
    background: var(--ink);
    color: var(--paper);
}

.site-nav a:focus-visible {
    position: relative;
    z-index: 1;
    outline-offset: -3px;
}

#planes,
#registro,
#proyectos,
#servicios {
    scroll-margin-top: 95px;
}

@media (max-width: 900px) {
    .site-nav {
        top: 70px;
        right: 20px;
        left: 20px;
        max-width: none;
        overflow-x: auto;
        transform: none;
        scrollbar-width: thin;
    }

    .site-nav ul {
        width: max-content;
        min-width: 100%;
    }

    .site-nav li {
        flex: 1 0 auto;
    }

    .site-nav a {
        text-align: center;
    }

    #planes,
    #registro,
    #proyectos,
    #servicios {
        scroll-margin-top: 125px;
    }
}

@media (max-width: 600px) {
    .site-nav ul { display: grid; grid-template-columns: 1fr 1fr; width: 100%; }
    .site-nav li:nth-child(3) { border-left: 0; }
    .site-nav li:nth-child(n + 3) { border-top: 1px solid var(--line); }
    .site-nav a { padding: 13px 7px; }
    #planes, #registro, #proyectos, #servicios { scroll-margin-top: 165px; }
}

@media (prefers-reduced-motion: reduce) {
    .site-nav {
        scroll-behavior: auto;
    }
}