/* ===== BOTÓN SUBIR ===== */
.scroll-top {
    position: fixed;
    bottom: 30px;
    right: 30px;
    width: 60px;
    height: 60px;
    border-radius: 50%;
    background: var(--bg-card);
    backdrop-filter: blur(10px);
    border: 2px solid transparent;
    background: linear-gradient(var(--bg-card), var(--bg-card)) padding-box,
                var(--gradient) border-box;
    display: flex;
    align-items: center;
    justify-content: center;
    color: var(--text-primary);
    text-decoration: none;
    font-size: 2rem;
    z-index: 100;
    opacity: 0;
    visibility: hidden;
    transition: all 0.4s cubic-bezier(0.4, 0, 0.2, 1);
    box-shadow: 0 10px 30px var(--shadow-primary);
    cursor: pointer;
    transform: scale(0.9);
}

.scroll-top.visible {
    opacity: 1;
    visibility: visible;
    transform: scale(1);
    animation: fadeIn 0.5s ease;
}

.scroll-top:hover {
    background: var(--gradient);
    border-color: transparent;
    transform: translateY(-5px) scale(1.1);
    box-shadow: 0 20px 40px var(--shadow-secondary);
}

.scroll-top::before {
    content: '';
    position: absolute;
    top: 0;
    left: -100%;
    width: 100%;
    height: 100%;
    background: linear-gradient(90deg, transparent, var(--white-02), transparent);
    transition: left 0.5s ease;
    border-radius: 50%;
}

.scroll-top:hover::before {
    left: 100%;
}