/* ========== BASE & RESET ========== */
*, *::before, *::after {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

html {
    scroll-behavior: smooth;
    -webkit-text-size-adjust: 100%;
}

body {
    font-family: 'Inter', system-ui, sans-serif;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
    overflow-x: hidden;
}

img {
    max-width: 100%;
    height: auto;
    display: block;
}

a {
    text-decoration: none;
    color: inherit;
}

/* ========== SCROLL REVEAL (progressive enhancement) ========== */
@media (prefers-reduced-motion: no-preference) {
    .reveal {
        opacity: 0;
        transform: translateY(30px);
        transition: opacity 0.8s cubic-bezier(0.16, 1, 0.3, 1),
                    transform 0.8s cubic-bezier(0.16, 1, 0.3, 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; }
}

/* ========== NAVBAR ========== */
#navbar {
    background: transparent;
    transition: background-color 0.4s ease, box-shadow 0.4s ease, backdrop-filter 0.4s ease;
}

#navbar.scrolled {
    background: rgba(10, 31, 63, 0.95);
    backdrop-filter: blur(12px);
    box-shadow: 0 1px 0 rgba(94, 234, 212, 0.08);
}

.nav-link {
    position: relative;
}

.nav-link::after {
    content: '';
    position: absolute;
    bottom: -4px;
    left: 0;
    width: 0;
    height: 1px;
    background: #5eead4;
    transition: width 0.3s ease;
}

.nav-link:hover::after {
    width: 100%;
}

/* ========== MOBILE MENU ========== */
#mobile-menu.open {
    opacity: 1;
    pointer-events: all;
}

/* ========== HERO ========== */
#hero {
    position: relative;
}

/* ========== SECTION DIVIDER ========== */
.section-divider {
    height: 1px;
    background: linear-gradient(90deg, transparent, rgba(94, 234, 212, 0.2), transparent);
}

/* ========== GEAR CARDS ========== */
#gear .group {
    position: relative;
}

/* ========== CUSTOM SCROLLBAR ========== */
::-webkit-scrollbar {
    width: 8px;
}

::-webkit-scrollbar-track {
    background: #0a1f3f;
}

::-webkit-scrollbar-thumb {
    background: #153d7a;
    border-radius: 4px;
}

::-webkit-scrollbar-thumb:hover {
    background: #1a4a96;
}

/* ========== SELECTION ========== */
::selection {
    background: rgba(94, 234, 212, 0.25);
    color: #f0fdf9;
}

/* ========== FOCUS ========== */
:focus-visible {
    outline: 2px solid #5eead4;
    outline-offset: 2px;
}

/* ========== UTILITY ========== */
.sr-only {
    position: absolute;
    width: 1px;
    height: 1px;
    padding: 0;
    margin: -1px;
    overflow: hidden;
    clip: rect(0, 0, 0, 0);
    white-space: nowrap;
    border-width: 0;
}