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

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

body {
    margin: 0;
    overflow-x: hidden;
}

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

/* ========== NAVIGATION ========== */
.nav-header {
    background: transparent;
    transition: background 0.4s ease, box-shadow 0.4s ease, backdrop-filter 0.4s ease;
}

.nav-header.scrolled {
    background: rgba(254, 252, 251, 0.92);
    backdrop-filter: blur(16px);
    -webkit-backdrop-filter: blur(16px);
    box-shadow: 0 1px 20px rgba(0, 0, 0, 0.06);
}

.nav-link {
    position: relative;
}

/* ========== HERO ANIMATIONS ========== */
.hero-anim {
    opacity: 0;
    transform: translateY(30px);
    animation: heroReveal 0.8s cubic-bezier(0.16, 1, 0.3, 1) forwards;
}

.hero-anim:nth-child(1) { animation-delay: 0.1s; }
.hero-anim:nth-child(2) { animation-delay: 0.25s; }
.hero-anim:nth-child(3) { animation-delay: 0.4s; }
.hero-anim:nth-child(4) { animation-delay: 0.55s; }

@keyframes heroReveal {
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

/* ========== SCROLL REVEAL ========== */
.scroll-reveal {
    opacity: 0;
    transform: translateY(40px);
    transition: opacity 0.7s cubic-bezier(0.16, 1, 0.3, 1), transform 0.7s cubic-bezier(0.16, 1, 0.3, 1);
}

.scroll-reveal.revealed {
    opacity: 1;
    transform: translateY(0);
}

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

#mobile-menu.closed {
    opacity: 0;
    pointer-events: none;
}

.mobile-link {
    opacity: 0;
    transform: translateY(15px);
    transition: opacity 0.3s ease, transform 0.3s ease, color 0.2s ease;
}

#mobile-menu.open .mobile-link {
    opacity: 1;
    transform: translateY(0);
}

#mobile-menu.open .mobile-link:nth-child(1) { transition-delay: 0.1s; }
#mobile-menu.open .mobile-link:nth-child(2) { transition-delay: 0.15s; }
#mobile-menu.open .mobile-link:nth-child(3) { transition-delay: 0.2s; }

/* ========== HAMBURGER ANIMATION ========== */
#menu-btn[aria-expanded="true"] #bar1 {
    transform: translateY(4px) rotate(45deg);
}

#menu-btn[aria-expanded="true"] #bar2 {
    opacity: 0;
    transform: scaleX(0);
}

#menu-btn[aria-expanded="true"] #bar3 {
    transform: translateY(-4px) rotate(-45deg);
    width: 100%;
}

/* ========== BACK TO TOP ========== */
#back-to-top.visible {
    opacity: 1;
    pointer-events: all;
}

/* ========== SECTION DIVIDER WAVE ========== */
.section-divider {
    position: relative;
    overflow: hidden;
}

.section-divider::after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 0;
    right: 0;
    height: 40px;
    background: inherit;
    clip-path: ellipse(55% 100% at 50% 100%);
}

/* ========== REDUCED MOTION ========== */
@media (prefers-reduced-motion: reduce) {
    *, *::before, *::after {
        animation-duration: 0.01ms !important;
        animation-iteration-count: 1 !important;
        transition-duration: 0.01ms !important;
    }
    
    html {
        scroll-behavior: auto;
    }
    
    .scroll-reveal {
        opacity: 1;
        transform: none;
    }
    
    .hero-anim {
        opacity: 1;
        transform: none;
    }
}

/* ========== ACCESSIBILITY FOCUS ========== */
a:focus-visible,
button:focus-visible {
    outline: 2px solid #d44a28;
    outline-offset: 3px;
    border-radius: 4px;
}

/* ========== SELECTION ========== */
::selection {
    background: #f2b8a8;
    color: #3d0f08;
}