/* === CUSTOM SCROLLBAR === */
/* For WebKit browsers (Chrome, Safari, Edge) */
::-webkit-scrollbar {
    width: 12px;
    height: 12px;
}

::-webkit-scrollbar-track {
    background: var(--light-1);
    border-radius: 10px;
}

::-webkit-scrollbar-thumb {
    background: var(--primary);
    border-radius: 10px;
    border: 3px solid var(--light-1);
    transition: all var(--transition-normal);
}

::-webkit-scrollbar-thumb:hover {
    background: var(--primary-dark);
}

/* For Firefox */
* {
    scrollbar-width: thin;
    scrollbar-color: var(--primary) var(--light-1);
}

/* === ENHANCED SCROLL PROGRESS BAR === */
.scroll-progress {
    position: fixed;
    top: 0;
    left: 0;
    width: 0%;
    height: 4px;
    background: linear-gradient(90deg, 
        var(--secondary) 0%, 
        var(--secondary-light) 25%, 
        var(--primary-light) 50%, 
        var(--primary) 75%, 
        var(--primary-dark) 100%);
    z-index: 9999;
    transition: width 0.1s ease;
    box-shadow: 0 2px 10px rgba(58, 156, 141, 0.3);
    border-radius: 0 2px 2px 0;
    overflow: hidden;
}

.scroll-progress::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: linear-gradient(90deg, 
        transparent, 
        rgba(255, 255, 255, 0.4), 
        transparent);
    animation: shimmer 2s infinite;
}

@keyframes shimmer {
    0% {
        transform: translateX(-100%);
    }
    100% {
        transform: translateX(100%);
    }
}

/* ==================== BOUTON RETOUR EN HAUT ==================== */
.back-to-top {
    position: fixed;
    bottom: 110px;
    right: 35px;
    width: 50px;
    height: 50px;
    background: linear-gradient(135deg, var(--primary), var(--primary-dark));
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    color: var(--white);
    font-size: 1.2rem;
    cursor: pointer;
    z-index: 999;
    opacity: 0;
    visibility: hidden;
    transform: translateY(20px);
    transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
    box-shadow: 0 4px 15px rgba(66, 183, 165, 0.3);
    border: 2px solid rgba(255, 255, 255, 0.2);
}

.back-to-top.visible {
    opacity: 1;
    visibility: visible;
    transform: translateY(0);
}

.back-to-top:hover {
    background: linear-gradient(135deg, var(--primary-dark), var(--primary));
    transform: translateY(-5px) scale(1.1);
    box-shadow: 0 8px 25px rgba(66, 183, 165, 0.4);
}

.back-to-top:active {
    transform: translateY(-2px) scale(1.05);
}

/* Effet de pulsation */
.back-to-top::after {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    border-radius: 50%;
    background: linear-gradient(135deg, var(--primary), var(--primary-dark));
    z-index: -1;
    animation: pulse 2s infinite;
    opacity: 0.5;
}

@keyframes pulse {
    0% {
        transform: scale(1);
        opacity: 0.5;
    }
    50% {
        transform: scale(1.2);
        opacity: 0.3;
    }
    100% {
        transform: scale(1);
        opacity: 0.5;
    }
}

/* ==================== RESPONSIVE ==================== */
@media (max-width: 768px) {
    .back-to-top {
        width: 45px;
        height: 45px;
        bottom: 100px;
        right: 20px;
        font-size: 1.1rem;
    }
}

@media (max-width: 480px) {
    .back-to-top {
        width: 40px;
        height: 40px;
        bottom: 90px;
        right: 15px;
        font-size: 1rem;
    }
}

/* Mode réduction des mouvements */
@media (prefers-reduced-motion: reduce) {
    .back-to-top {
        transition: opacity 0.3s ease;
    }
    
    .back-to-top:hover {
        transform: translateY(0);
    }
    
    .back-to-top::after {
        animation: none;
    }
}