/* 页脚样式 */
#footer {
    background-color: #1a1a1a;
    color: #fff;
    padding: 40px 0 20px;
}

.footer-content {
    display: flex;
    justify-content: space-between;
    gap: 60px;
    padding: 40px 0 20px;
}

.footer-info {
    flex: 1;
    max-width: 500px;
}

.footer-logo h2 {
    color: #fff;
    font-size: 24px;
    font-weight: 700;
    margin-bottom: 15px;
}

.company-slogan {
    color: #999;
    font-size: 14px;
    line-height: 1.5;
    margin-bottom: 20px;
}

.contact-info {
    display: flex;
    flex-direction: column;
    gap: 15px;
}

.contact-item {
    display: flex;
    align-items: flex-start;
    gap: 15px;
}

.contact-item i {
    color: #e60012;
    font-size: 16px;
    margin-top: 2px;
}

.contact-item div {
    display: flex;
    gap: 5px;
}

.contact-item strong {
    color: #fff;
    font-size: 14px;
    font-weight: 600;
}

.contact-item span {
    color: #999;
    font-size: 14px;
    line-height: 1.4;
}



.footer-nav h3 {
    color: #fff;
    font-size: 18px;
    font-weight: 600;
    margin-bottom: 20px;
    position: relative;
    padding-bottom: 12px;
}

.footer-nav h3::after {
    content: '';
    position: absolute;
    left: 0;
    bottom: 0;
    width: 40px;
    height: 3px;
    background-color: #e60012;
}

.nav-columns {
    display: flex;
    gap: 40px;
}

.nav-column ul {
    list-style: none;
    padding: 0;
    margin: 0;
}

.nav-column ul li {
    margin-bottom: 12px;
}

.nav-column ul li a {
    color: #999;
    text-decoration: none;
    font-size: 14px;
    transition: all 0.3s ease;
    display: inline-block;
}

.nav-column ul li a:hover {
    color: #fff;
    transform: translateX(5px);
}

.copyright {
    border-top: 1px solid #333;
    margin-top: 30px;
    padding-top: 20px;
    text-align: center;
    color: #666;
    font-size: 13px;
}

/* 媒体查询适配 */
@media screen and (max-width: 992px) {
    .footer-content {
        gap: 40px;
    }

    .footer-nav {
        flex: 0 0 350px;
    }
}

@media screen and (max-width: 768px) {
    #footer {
        padding: 30px 0 15px;
    }

    .footer-content {
        flex-direction: column;
        gap: 30px;
        padding: 20px 0 15px;
    }

    .footer-info,
    .footer-links {
        max-width: 100%;
    }

    .footer-logo h2 {
        font-size: 20px;
        text-align: center;
    }

    .company-slogan {
        text-align: center;
    }

    .nav-columns {
        gap: 20px;
        justify-content: center;
    }

    .footer-nav {
        flex: 0 0 auto;
    }

    .footer-nav h3 {
        text-align: center;
    }

    .footer-nav h3::after {
        left: 50%;
        transform: translateX(-50%);
    }

    .contact-info {
        align-items: center;
    }

    /* 联系方式在手机端的样式优化 */
    .contact-item {
        width: 100%;
        max-width: 320px;
    }

    .contact-item div {
        flex-direction: row;
        flex-wrap: wrap;
        gap: 2px;
    }

    .contact-item div span {
        width: 100%;
        word-break: break-word;
        margin-top: 2px;
    }
}

@media screen and (max-width: 480px) {
    #footer {
        padding: 25px 15px 15px;
    }

    .footer-content {
        padding: 15px 0 10px;
        gap: 25px;
    }

    .footer-logo h2 {
        font-size: 18px;
    }

    .company-slogan {
        font-size: 12px;
        margin-bottom: 15px;
    }

    .nav-columns {
        flex-direction: column;
        align-items: center;
        gap: 5px;
    }

    .nav-column {
        width: 100%;
    }

    .nav-column ul li {
        margin-bottom: 8px;
    }

    .nav-column ul li a {
        font-size: 13px;
    }

    .nav-column ul li a:hover {
        transform: none;
    }

    .contact-item {
        width: 100%;
        align-items: flex-start;
    }

    .contact-item i {
        font-size: 14px;
        margin-top: 3px;
    }

    .contact-item div {
        flex-direction: column;
        align-items: flex-start;
    }

    .contact-item strong,
    .contact-item span {
        font-size: 13px;
        line-height: 1.3;
    }

    .back-to-top {
        bottom: 20px;
        right: 20px;
        width: 35px;
        height: 35px;
    }

    .copyright {
        font-size: 12px;
        margin-top: 20px;
        padding-top: 15px;
    }
}

/* 回到顶部按钮 */
.back-to-top {
    position: fixed;
    bottom: 30px;
    right: 30px;
    width: 40px;
    height: 40px;
    background-color: #e60012;
    color: #fff;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    opacity: 0;
    visibility: hidden;
    z-index: 999;
    transition: all 0.3s ease;
    box-shadow: 0 2px 10px rgba(0, 0, 0, 0.1);
}

.back-to-top.active {
    opacity: 1;
    visibility: visible;
}

.back-to-top:hover {
    background-color: #e60022;
    transform: translateY(-5px);
}