/* Back to top button */
.back-to-top {
    position: fixed;
    bottom: 30px;
    right: 30px;
    width: 50px;
    height: 50px;
    background: rgba(255, 255, 255, 0.95);
    border: none;
    border-radius: 50%;
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    box-shadow: 0 4px 15px rgba(0, 0, 0, 0.2);
    transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
    opacity: 0;
    visibility: hidden;
    transform: translateY(20px) scale(0.8);
    z-index: 9999;
    color: #333;
    pointer-events: none;
}

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

.back-to-top:hover {
    background: rgba(255, 165, 0, 0.95);
    color: white;
    transform: translateY(-5px);
    box-shadow: 0 6px 20px rgba(255, 165, 0, 0.4);
}

.back-to-top:active {
    transform: translateY(-2px) scale(0.95);
}

.back-to-top svg {
    width: 24px;
    height: 24px;
    pointer-events: none;
}

/* Dark mode support */
body.darkmode .back-to-top {
    background: rgba(50, 50, 60, 0.95);
    color: #fff;
}

body.darkmode .back-to-top:hover {
    background: rgba(255, 165, 0, 0.95);
    color: white;
}

/* Mobile optimization */
@media (max-width: 768px) {
    .back-to-top {
        bottom: 20px;
        right: 20px;
        width: 45px;
        height: 45px;
    }
}