.back-to-top {
    position: fixed;
    bottom: 30px;
    right: 30px;
    width: 45px;
    height: 45px;
    background: rgba(255, 255, 255, 0.8);
    webkit-backdrop-filter: blur(5px);
    border: 2px solid #4f46e5;
    color: #4f46e5;
    border-radius: 50%;
    font-size: 1.2rem;
    font-weight: bold;
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    z-index: 999;
    
    opacity: 0;
    visibility: hidden;
    transform: translateY(20px);
    transition: all 0.3s ease;
    box-shadow: 0 5px 15px rgba(0,0,0,0.1);
}

/* JS ile eklenecek */
.back-to-top.show {
    opacity: 1;
    visibility: visible;
    transform: translateY(0);
}

.back-to-top:hover {
    background: #4f46e5;
    color: white;
    transform: translateY(-5px);
    box-shadow: 0 10px 20px rgba(79, 70, 229, 0.3);
}

/* Dark Mode to top */
body.dark-mode .back-to-top {
    background: rgba(15, 23, 42, 0.8);
    border-color: #38bdf8;
    color: #38bdf8;
}
body.dark-mode .back-to-top:hover {
    background: #38bdf8;
    color: #0f172a;
}