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

html {
    scroll-behavior: smooth;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

body {
    overflow-x: hidden;
}

/* Scroll Reveal - progressive enhancement, hidden by default, shown via JS */
.scroll-reveal {
    opacity: 1;
    transform: none;
    transition: opacity 0.6s ease, transform 0.6s ease;
}

@media (prefers-reduced-motion: no-preference) {
    .scroll-reveal.revealed {
        opacity: 1;
        transform: translateY(0);
    }

    .scroll-reveal:not(.revealed) {
        opacity: 0;
        transform: translateY(24px);
    }
}

/* Navbar scroll state */
nav.scrolled {
    background: rgba(255, 255, 255, 0.95) !important;
    backdrop-filter: blur(12px);
    -webkit-backdrop-filter: blur(12px);
    box-shadow: 0 1px 20px rgba(13, 148, 136, 0.08);
}

nav.scrolled .font-serif {
    color: #0f766e !important;
}

/* Custom selection color */
::selection {
    background: #99f6e4;
    color: #134e4a;
}

/* Smooth image loading */
img {
    image-rendering: -webkit-optimize-contrast;
}

/* Custom scrollbar */
::-webkit-scrollbar {
    width: 8px;
}

::-webkit-scrollbar-track {
    background: #f0fdfa;
}

::-webkit-scrollbar-thumb {
    background: #99f6e4;
    border-radius: 4px;
}

::-webkit-scrollbar-thumb:hover {
    background: #5eead4;
}

/* Focus styles */
a:focus-visible,
button:focus-visible,
input:focus-visible,
textarea:focus-visible {
    outline: 2px solid #2dd4bf;
    outline-offset: 2px;
    border-radius: 4px;
}

/* Mobile menu animation */
#mobile-menu {
    animation: slideDown 0.3s ease;
}

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

/* Back to top button animation */
#back-to-top.visible {
    opacity: 1;
    pointer-events: auto;
    transform: translateY(0);
}

#back-to-top:not(.visible) {
    opacity: 0;
    pointer-events: none;
    transform: translateY(16px);
}

/* Decorative floating animation */
@keyframes float {
    0%, 100% { transform: translateY(0px); }
    50% { transform: translateY(-10px); }
}

/* Gradient text utility */
.text-gradient {
    background: linear-gradient(135deg, #0d9488, #14b8a6);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}