/* Variables & Root */
:root {
    --primary-color: #3b82f6;      /* Blue 600 */
    --primary-dark: #1d4ed8;       /* Blue 700 */
    --primary-light: #eff6ff;      /* Blue 50 */
    --text-dark: #1e293b;          /* Slate 800 */
    --text-light: #ffffff;
    --border-color: #f1f5f9;       /* Slate 100 */
    --shadow-color: rgba(0, 0, 0, 0.05);
    --shadow-hover: rgba(59, 130, 246, 0.3);
}

/* Root & Smooth Scroll */
html {
    scroll-behavior: smooth;
    -webkit-user-select: none; /* Safari */
    -moz-user-select: none;    /* Firefox */
    -ms-user-select: none;     /* IE10+/Edge */
    user-select: none;         /* Standard */
}

body {
    -webkit-font-smoothing: antialiased;
    overflow-x: hidden;
}

/* Timeline - Animazioni di ingresso */
.timeline-item {
    opacity: 0;
    transform: translateY(20px);
    transition: all 0.7s ease-out;
}

.timeline-item.visible {
    opacity: 1;
    transform: translateY(0);
}

/* Skills Grid - Responsive Cards with Fixed Icons */
.skill-card-container {
    position: relative;
    width: 100%;
    aspect-ratio: 1 / 1; 
    z-index: 10;
    perspective: 1000px; 
}

.skill-card {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    background-color: var(--text-light);
    border-radius: 2rem;
    border: 1px solid var(--border-color);
    transition: background-color 0.3s ease, border-color 0.3s ease, box-shadow 0.3s ease, transform 0.1s ease-out;
    padding: 1.5rem;
    box-shadow: 0 4px 6px -1px var(--shadow-color);
    transform-style: preserve-3d;
    backface-visibility: hidden;
}

.skill-card:hover {
    background-color: var(--primary-color); 
    border-color: var(--primary-color);
    z-index: 50;
    box-shadow: 0 20px 25px -5px var(--shadow-hover);
}

.icon-box {
    width: 64px; 
    height: 64px;
    display: flex;
    align-items: center;
    justify-content: center;
    transition: transform 0.3s ease;
    margin-bottom: 0.75rem;
    pointer-events: none; /* Risolve sparizioni e flicker */
    transform: translateZ(20px);
}

/* Riduzione icona solo su mobile estremo per evitare overlap */
@media (max-width: 400px) {
    .icon-box {
        width: 48px;
        height: 48px;
    }
}

.skill-card:hover .icon-box {
    transform: scale(1.1) translateZ(30px);
}

.skill-icon {
    width: 100%;
    height: 100%;
    object-fit: contain;
    pointer-events: none;
}

.skill-name {
    transition: color 0.3s ease;
    font-size: 1rem;
    font-weight: 800;
    text-align: center;
    color: var(--text-dark);
    pointer-events: none;
    transform: translateZ(15px);
}

.skill-card:hover .skill-name {
    color: var(--text-light);
}

/* Animations from Contact Page */
@keyframes bounce-slow {
    0%, 100% { transform: translateY(0); }
    50% { transform: translateY(-10px); }
}

.animate-bounce-slow {
    animation: bounce-slow 3s ease-in-out infinite;
}

/* Sky Gradients */
.sky-dawn { background: linear-gradient(135deg, #ff9a9e 0%, #fad0c4 99%, #fad0c4 100%); }
.sky-day { background: linear-gradient(135deg, #4facfe 0%, #00f2fe 100%); }
.sky-sunset { background: linear-gradient(135deg, #fa709a 0%, #fee140 100%); }
.sky-night { background: linear-gradient(135deg, #0f172a 0%, #1e293b 100%); }