*, *::before, *::after {
    box-sizing: border-box;
}

html {
    scroll-behavior: smooth;
}

body {
    overflow-x: hidden;
}

::selection {
    background-color: #2dd4bf;
    color: #0f172a;
}

/* Scrollbar */
::-webkit-scrollbar {
    width: 8px;
}
::-webkit-scrollbar-track {
    background: #0f172a;
}
::-webkit-scrollbar-thumb {
    background: #334155;
    border-radius: 4px;
}
::-webkit-scrollbar-thumb:hover {
    background: #2dd4bf;
}

/* Reduced motion */
@media (prefers-reduced-motion: reduce) {
    html {
        scroll-behavior: auto;
    }
    .fade-up, .fade-down, .fade-in {
        opacity: 1 !important;
        transform: none !important;
        transition: none !important;
    }
}

/* Reveal animations — progressive enhancement, JS adds class */
.fade-up {
    opacity: 0;
    transform: translateY(30px);
    transition: opacity 0.7s ease, transform 0.7s ease;
}
.fade-up.is-visible {
    opacity: 1;
    transform: translateY(0);
}

.fade-down {
    opacity: 0;
    transform: translateY(-20px);
    transition: opacity 0.6s ease, transform 0.6s ease;
}
.fade-down.is-visible {
    opacity: 1;
    transform: translateY(0);
}

.fade-in {
    opacity: 0;
    transition: opacity 0.8s ease;
}
.fade-in.is-visible {
    opacity: 1;
}

/* Stagger children */
.stagger-children > * {
    opacity: 0;
    transform: translateY(20px);
    transition: opacity 0.5s ease, transform 0.5s ease;
}
.stagger-children.is-visible > *:nth-child(1) { transition-delay: 0.05s; opacity: 1; transform: translateY(0); }
.stagger-children.is-visible > *:nth-child(2) { transition-delay: 0.1s; opacity: 1; transform: translateY(0); }
.stagger-children.is-visible > *:nth-child(3) { transition-delay: 0.15s; opacity: 1; transform: translateY(0); }
.stagger-children.is-visible > *:nth-child(4) { transition-delay: 0.2s; opacity: 1; transform: translateY(0); }
.stagger-children.is-visible > *:nth-child(5) { transition-delay: 0.25s; opacity: 1; transform: translateY(0); }
.stagger-children.is-visible > *:nth-child(6) { transition-delay: 0.3s; opacity: 1; transform: translateY(0); }

/* Navbar scroll state */
.nav-scrolled {
    box-shadow: 0 4px 30px rgba(0, 0, 0, 0.3);
}

/* Button focus styles */
button:focus-visible,
a:focus-visible,
input:focus-visible,
select:focus-visible,
textarea:focus-visible {
    outline: 2px solid #2dd4bf;
    outline-offset: 2px;
}

/* Form select arrow */
select {
    appearance: none;
    background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='12' height='12' viewBox='0 0 24 24' fill='none' stroke='%2394a3b8' stroke-width='2' stroke-linecap='round' stroke-linejoin='round'%3E%3Cpolyline points='6 9 12 15 18 9'%3E%3C/polyline%3E%3C/svg%3E");
    background-repeat: no-repeat;
    background-position: right 1rem center;
    padding-right: 2.5rem;
}