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

html {
    scroll-behavior: smooth;
    scroll-padding-top: 80px;
}

body {
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

::selection {
    background: rgba(46, 196, 166, 0.3);
    color: #050A18;
}

/* ─── HEADER ─── */
#header {
    background: transparent;
    transition: background 0.4s ease, box-shadow 0.4s ease;
}

#header.scrolled {
    background: rgba(5, 10, 24, 0.95);
    backdrop-filter: blur(12px);
    box-shadow: 0 1px 0 rgba(255,255,255,0.05);
}

.nav-link {
    position: relative;
}

.nav-link::after {
    content: '';
    position: absolute;
    bottom: -4px;
    left: 0;
    width: 0;
    height: 2px;
    background: #2EC4A6;
    transition: width 0.3s ease;
}

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

/* ─── MOBILE MENU ─── */
.mobile-menu-overlay.active {
    opacity: 1;
    pointer-events: all;
}

.mobile-menu.active {
    transform: translateX(0);
}

/* ─── HERO ─── */
.hero {
    position: relative;
}

.hero-bg {
    will-change: transform;
}

.hero-img {
    will-change: transform;
}

.floating-card {
    animation: float 6s ease-in-out infinite;
}

.card-1 { animation-delay: 0s; }
.card-2 { animation-delay: -1.5s; }
.card-3 { animation-delay: -3s; }
.card-4 { animation-delay: -4.5s; }

@keyframes float {
    0%, 100% { transform: translateY(0px); }
    50% { transform: translateY(-12px); }
}

.scroll-dot {
    animation: scrollBounce 1.5s ease-in-out infinite;
}

@keyframes scrollBounce {
    0%, 100% { top: 0; }
    50% { top: 24px; }
}

/* ─── BUTTONS ─── */
.btn-primary, .btn-secondary {
    position: relative;
    overflow: hidden;
}

.btn-primary::before {
    content: '';
    position: absolute;
    top: 0;
    left: -100%;
    width: 100%;
    height: 100%;
    background: linear-gradient(90deg, transparent, rgba(255,255,255,0.15), transparent);
    transition: left 0.5s ease;
}

.btn-primary:hover::before {
    left: 100%;
}

/* ─── SERVICE CARDS ─── */
.service-card {
    position: relative;
    overflow: hidden;
}

.service-card::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    height: 3px;
    background: linear-gradient(90deg, #2EC4A6, #4FD4B5);
    transform: scaleX(0);
    transform-origin: left;
    transition: transform 0.4s ease;
}

.service-card:hover::before {
    transform: scaleX(1);
}

/* ─── PROJECT CARDS ─── */
.project-card {
    position: relative;
}

.project-card::after {
    content: '';
    position: absolute;
    inset: 0;
    border-radius: 16px;
    border: 1px solid transparent;
    transition: border-color 0.4s ease;
    pointer-events: none;
}

.project-card:hover::after {
    border-color: rgba(46, 196, 166, 0.3);
}

/* ─── TESTIMONIAL CARDS ─── */
.testimonial-card {
    position: relative;
}

.testimonial-card::before {
    content: '"';
    position: absolute;
    top: 16px;
    right: 24px;
    font-family: 'Playfair Display', serif;
    font-size: 6rem;
    font-weight: 900;
    color: rgba(46, 196, 166, 0.08);
    line-height: 1;
    pointer-events: none;
}

/* ─── SCROLL REVEAL ─── */
.reveal {
    opacity: 1;
    transform: none;
    transition: opacity 0.8s ease, transform 0.8s ease;
}

.reveal[data-reveal] {
    opacity: 0;
    transform: translateY(32px);
}

@media (prefers-reduced-motion: no-preference) {
    .reveal[data-reveal] {
        opacity: 0;
        transform: translateY(32px);
    }
    
    .reveal.visible[data-reveal] {
        opacity: 1;
        transform: translateY(0);
    }
    
    .reveal[data-reveal="left"] {
        transform: translateX(-32px);
    }
    
    .reveal[data-reveal="left"].visible {
        transform: translateX(0);
    }
    
    .reveal[data-reveal="right"] {
        transform: translateX(32px);
    }
    
    .reveal[data-reveal="right"].visible {
        transform: translateX(0);
    }
}

/* stagger children */
.reveal.visible ~ .reveal[data-delay="100"] { transition-delay: 0.1s; }
.reveal.visible ~ .reveal[data-delay="200"] { transition-delay: 0.2s; }
.reveal.visible ~ .reveal[data-delay="300"] { transition-delay: 0.3s; }
.reveal.visible ~ .reveal[data-delay="400"] { transition-delay: 0.4s; }

/* ─── FORM ─── */
.btn-submit {
    position: relative;
    overflow: hidden;
}

.btn-submit::after {
    content: '';
    position: absolute;
    inset: 0;
    background: linear-gradient(90deg, transparent, rgba(46,196,166,0.2), transparent);
    transform: translateX(-100%);
    transition: transform 0.6s ease;
}

.btn-submit:hover::after {
    transform: translateX(100%);
}

/* ─── BACK TO TOP ─── */
#backToTop a {
    transition: background 0.3s ease, transform 0.3s ease, opacity 0.3s ease;
}

#backToTop.visible a {
    opacity: 1;
    transform: translateY(0);
    pointer-events: all;
}

/* ─── UTILITY ─── */
@media (max-width: 640px) {
    html {
        scroll-padding-top: 72px;
    }
}