/* === 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;
}

::selection {
    background: #0d9488;
    color: #fff;
}

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

#navbar.scrolled {
    background: rgba(255, 255, 255, 0.95);
    backdrop-filter: blur(12px);
    box-shadow: 0 1px 0 rgba(0, 0, 0, 0.06);
}

.nav-logo-text {
    transition: color 0.4s ease;
}

#navbar.scrolled .nav-logo-text {
    color: #0f172a;
}

/* === Hero === */
.hero-headline {
    letter-spacing: -0.02em;
}

/* === Section Transitions === */
.fade-in {
    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);
}

.fade-in.visible {
    opacity: 1;
    transform: translateY(0);
}

.fade-in-delay-1 { transition-delay: 0.1s; }
.fade-in-delay-2 { transition-delay: 0.2s; }
.fade-in-delay-3 { transition-delay: 0.3s; }
.fade-in-delay-4 { transition-delay: 0.4s; }

/* === Service Cards === */
.service-card {
    position: relative;
    overflow: hidden;
}

.service-card::after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 0;
    right: 0;
    height: 3px;
    background: #0d9488;
    transform: scaleX(0);
    transition: transform 0.4s cubic-bezier(0.16, 1, 0.3, 1);
    transform-origin: left;
}

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

/* === Buttons === */
.btn-primary {
    position: relative;
    overflow: hidden;
    transition: all 0.3s ease;
}

.btn-primary::before {
    content: '';
    position: absolute;
    inset: 0;
    background: linear-gradient(135deg, rgba(255,255,255,0.1) 0%, rgba(255,255,255,0) 100%);
    opacity: 0;
    transition: opacity 0.3s ease;
}

.btn-primary:hover::before {
    opacity: 1;
}

/* === Form === */
input:focus, textarea:focus {
    outline: none;
    box-shadow: 0 0 0 3px rgba(13, 148, 136, 0.1);
}

/* === Mobile Menu === */
#mobile-menu {
    animation: slideDown 0.3s cubic-bezier(0.16, 1, 0.3, 1);
}

@keyframes slideDown {
    from {
        opacity: 0;
        transform: translateY(-10px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

/* === Utility === */
@media (prefers-reduced-motion: reduce) {
    *, *::before, *::after {
        animation-duration: 0.01ms !important;
        transition-duration: 0.01ms !important;
    }
    html {
        scroll-behavior: auto;
    }
    .fade-in {
        opacity: 1;
        transform: none;
    }
}