/* Стили для кнопки "Наверх" */
.scroll-top-button {
    position: fixed;
    bottom: 30px;
    right: 30px;
    z-index: 1000;
    
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    gap: 8px;
    
    width: 70px;
    height: 70px;
    padding: 12px;
    
    background: linear-gradient(135deg, #ffffff 0%, #f8fafc 100%);
    border: 1px solid #e2e8f0;
    border-radius: 16px;
    box-shadow: 0 6px 12px rgba(0, 0, 0, 0.1), 0 4px 6px rgba(0, 0, 0, 0.05);
    
    cursor: pointer;
    opacity: 0;
    visibility: hidden;
    transform: translateY(20px) scale(0.9);
    transition: all 0.4s cubic-bezier(0.4, 0, 0.2, 1);
    
    font-family: 'Roboto', 'Arial', sans-serif;
    font-weight: 500;
    color: #2d3748;
    
    overflow: hidden;
}

.scroll-top-button::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    height: 3px;
    background: linear-gradient(90deg, #4299e1, #2c5282);
    transform: scaleX(0);
    transition: transform 0.3s ease;
}

.scroll-top-button:hover {
    transform: translateY(-2px) scale(1.05);
    box-shadow: 0 12px 25px rgba(0, 0, 0, 0.2), 0 8px 15px rgba(0, 0, 0, 0.15);
    color: #2c5282;
}

.scroll-top-button:hover::before {
    transform: scaleX(1);
}

.scroll-top-button:active {
    transform: translateY(0) scale(1);
    box-shadow: 0 4px 8px rgba(0, 0, 0, 0.15);
}

.scroll-top-button--visible {
    opacity: 1;
    visibility: visible;
    transform: translateY(0) scale(1);
}

.scroll-top-button__icon {
    width: 24px;
    height: 24px;
    display: flex;
    align-items: center;
    justify-content: center;
    transition: transform 0.3s ease;
}

.scroll-top-button:hover .scroll-top-button__icon {
    transform: translateY(-2px);
}

.scroll-top-button__text {
    font-size: 0.8rem;
    font-weight: 600;
    line-height: 1;
    text-align: center;
    transition: transform 0.3s ease;
}

.scroll-top-button:hover .scroll-top-button__text {
    transform: translateY(1px);
}

/* Адаптивность для кнопки */
@media screen and (max-width: 768px) {
    .scroll-top-button {
        bottom: 20px;
        right: 20px;
        width: 60px;
        height: 60px;
        gap: 6px;
    }
    
    .scroll-top-button__icon {
        width: 20px;
        height: 20px;
    }
    
    .scroll-top-button__icon svg {
        width: 18px;
        height: 18px;
    }
    
    .scroll-top-button__text {
        font-size: 0.75rem;
    }
}

@media screen and (max-width: 480px) {
    .scroll-top-button {
        bottom: 15px;
        right: 15px;
        width: 55px;
        height: 55px;
        border-radius: 14px;
    }
    
    .scroll-top-button__text {
        font-size: 0.7rem;
    }
}