/* ─── Base & Utilities ─── */
*, *::before, *::after {
    box-sizing: border-box;
}

html {
    scroll-behavior: smooth;
    scroll-padding-top: 5rem;
}

body {
    overflow-x: hidden;
}

/* ─── Scroll Reveal (progressive enhancement) ─── */
@media (prefers-reduced-motion: no-preference) {
    .reveal {
        opacity: 0;
        transform: translateY(24px);
        transition: opacity 0.7s cubic-bezier(0.22, 1, 0.36, 1), transform 0.7s cubic-bezier(0.22, 1, 0.36, 1);
    }
    .reveal.revealed {
        opacity: 1;
        transform: translateY(0);
    }
    .reveal-delay-1 { transition-delay: 0.1s; }
    .reveal-delay-2 { transition-delay: 0.2s; }
    .reveal-delay-3 { transition-delay: 0.3s; }
    .reveal-delay-4 { transition-delay: 0.4s; }
}

/* ─── Header scroll state ─── */
#site-header {
    background: transparent;
    transition: background 0.3s ease, box-shadow 0.3s ease, backdrop-filter 0.3s ease;
}

#site-header.scrolled {
    background: rgba(255, 255, 255, 0.92);
    backdrop-filter: blur(12px);
    -webkit-backdrop-filter: blur(12px);
    box-shadow: 0 1px 0 rgba(0, 0, 0, 0.06), 0 4px 20px rgba(0, 0, 0, 0.06);
}

/* ─── Nav links ─── */
.nav-link {
    position: relative;
}

.nav-link::after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 50%;
    width: 0;
    height: 2px;
    background: #0d9488;
    border-radius: 1px;
    transition: width 0.25s ease, left 0.25s ease;
}

.nav-link:hover::after {
    width: 60%;
    left: 20%;
}

/* ─── Mobile menu ─── */
#mobile-menu {
    animation: slideDown 0.25s ease;
}

@keyframes slideDown {
    from {
        opacity: 0;
        transform: translateY(-8px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

/* ─── Button hover lift ─── */
a[href="#contact"],
button[type="submit"] {
    will-change: transform;
}

/* ─── Image placeholder fallback ─── */
img {
    max-width: 100%;
    height: auto;
}

/* ─── Selection color ─── */
::selection {
    background: #99f6e4;
    color: #042f2e;
}
</script>