.back-to-top {
    position: fixed;
    bottom: 30px;
    right: 30px;
    width: 56px;
    height: 56px;
    background: #fff;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    cursor: pointer;
    z-index: 9998;
    box-shadow: 0 4px 20px rgba(0,0,0,0.15);
    opacity: 0;
    visibility: hidden;
    transform: translateY(20px);
    transition: all 0.3s ease;
}

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

.back-to-top:hover {
    transform: translateY(-4px);
    box-shadow: 0 8px 30px rgba(249, 115, 22, 0.3);
}

.back-to-top-inner {
    position: relative;
    width: 56px;
    height: 56px;
    display: flex;
    align-items: center;
    justify-content: center;
}

.back-to-top-svg {
    position: absolute;
    width: 56px;
    height: 56px;
    transform: rotate(-90deg);
}

.back-to-top-circle-bg {
    fill: none;
    stroke: #f0f0f0;
    stroke-width: 3;
}

.back-to-top-circle {
    fill: none;
    stroke: #F97316;
    stroke-width: 3;
    stroke-linecap: round;
    transition: stroke-dashoffset 0.3s ease;
}

.back-to-top i {
    font-size: 16px;
    color: #F97316;
    transition: all 0.3s ease;
    z-index: 2;
}

.back-to-top:hover i {
    color: #fff;
}

@media (max-width: 768px) {
    .back-to-top {
        bottom: 20px;
        right: 20px;
        width: 48px;
        height: 48px;
    }
    
    .back-to-top-inner,
    .back-to-top-svg {
        width: 48px;
        height: 48px;
    }
    
    .back-to-top i {
        font-size: 14px;
    }
}