/* 共用图标样式 */
.icon {
    width: 24px;
    height: 24px;
    fill: currentColor;
    display: inline-block;
}

.footer-column ul li svg {
    width: 20px;
    height: 20px;
    margin-right: 10px;
    fill: #6da8ff;
    vertical-align: middle;
}

.footer-column ul li {
    display: flex;
    align-items: center;
    gap: 10px;
}

/* 订阅区域样式 */
.footer-subscribe {
    background: rgba(255, 255, 255, 0.04);
    border-radius: 8px;
    padding: 30px;
    margin-bottom: 40px;
}

.subscribe-content {
    max-width: 600px;
    margin: 0 auto;
    text-align: center;
}

.subscribe-content h4 {
    font-size: 20px;
    margin-bottom: 10px;
    color: #ffffff;
}

.subscribe-content p {
    margin-bottom: 20px;
    color: #d0d0d0;
}

.subscribe-form {
    display: flex;
    max-width: 500px;
    margin: 0 auto;
}

.subscribe-form input {
    flex: 1;
    padding: 12px 15px;
    border: 1px solid rgba(255, 255, 255, 0.2);
    border-radius: 4px 0 0 4px;
    font-size: 14px;
    outline: none;
    background-color: rgba(0, 0, 0, 0.4);
    color: #ffffff;
}

.subscribe-form input::placeholder {
    color: rgba(255, 255, 255, 0.6);
}

.subscribe-form button {
    background-color: #4c8dff;
    color: #ffffff;
    border: none;
    padding: 0 25px;
    border-radius: 0 4px 4px 0;
    cursor: pointer;
    font-weight: 500;
    transition: background-color 0.3s ease;
}

.subscribe-form button:hover {
    background-color: #3a76e6;
}

/* 版权信息样式 */
.footer-copyright {
    display: flex;
    justify-content: space-between;
    align-items: center;
    flex-wrap: wrap;
    padding-top: 20px;
    border-top: 1px solid rgba(255, 255, 255, 0.08);
}

.copyright-text {
    margin-bottom: 15px;
}

.footer-social {
    display: flex;
    gap: 15px;
}

.footer-social a {
    display: flex;
    align-items: center;
    justify-content: center;
    width: 38px;
    height: 38px;
    background-color: rgba(255, 255, 255, 0.08);
    border-radius: 50%;
    color: #ffffff;
    text-decoration: none;
    font-size: 12px;
    font-weight: 600;
    letter-spacing: 0.5px;
    transition: all 0.3s ease;
}

.footer-social a:hover {
    background-color: rgba(108, 167, 255, 0.25);
    color: #ffffff;
    transform: translateY(-3px);
}

/* 返回顶部按钮 */
.back-to-top {
    position: fixed;
    bottom: 30px;
    right: 30px;
    width: 50px;
    height: 50px;
    background-color: #4c8dff;
    color: white;
    border: none;
    border-radius: 50%;
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    opacity: 0;
    visibility: hidden;
    transition: all 0.3s ease;
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.1);
    z-index: 999;
}

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

.back-to-top:hover {
    background-color: #3a76e6;
    transform: translateY(-3px);
}

/* 响应式设计 */
@media (max-width: 768px) {
    .footer-links {
        flex-direction: column;
    }
    
    .footer-column {
        padding-right: 0;
    }
    
    .footer-copyright {
        flex-direction: column;
        text-align: center;
    }
    
    .footer-social {
        margin-top: 15px;
        justify-content: center;
    }
    
    .subscribe-form {
        flex-direction: column;
    }
    
    .subscribe-form input {
        border-radius: 4px;
        margin-bottom: 10px;
    }
    
    .subscribe-form button {
        border-radius: 4px;
        padding: 12px;
    }
}

/* 页脚联系表单区域 */
.site-footer {
    background-color: #0f172a;
    color: #e2e8f0;
    padding: 32px 0;
}

.footer-contact-wrapper {
    max-width: 1080px;
    margin: 0 auto;
    padding: 0 20px 32px;
    display: grid;
    gap: 32px;
}

.footer-contact-panel {
    display: grid;
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: 24px;
    align-items: stretch;
}

.footer-contact-panel > * {
    background: rgba(15, 23, 42, 0.35);
    border: 1px solid rgba(148, 163, 184, 0.18);
    border-radius: 12px;
    padding: 24px;
    display: flex;
    flex-direction: column;
    gap: 20px;
    color: #e2e8f0;
    box-shadow: none;
}

.footer-contact-title {
    font-size: 18px;
    font-weight: 600;
    margin: 0 0 12px;
    color: #f8fafc;
    letter-spacing: 0.02em;
}

.footer-bottom {
    border-top: 1px solid rgba(148, 163, 184, 0.18);
    padding: 20px 0 0;
    text-align: center;
}

.footer-bottom__text {
    margin: 0;
    font-size: 13px;
    letter-spacing: 0.02em;
    color: #94a3b8;
}

.footer-contact-list {
    list-style: none;
    padding: 0;
    margin: 0;
    display: grid;
    gap: 10px;
    font-size: 14px;
    color: #cbd5f5;
}

.footer-contact-list li {
    display: flex;
    gap: 8px;
    align-items: baseline;
}

.footer-contact-list li span {
    font-weight: 600;
    color: #f8fafc;
    flex-shrink: 0;
}

.footer-contact-list a {
    color: #38bdf8;
    text-decoration: none;
}

.footer-contact-list a:hover {
    text-decoration: underline;
}

.footer-message-form {
    display: grid;
    gap: 20px;
}

.footer-form-grid {
    display: grid;
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: 16px;
}

.footer-form-field {
    display: flex;
    flex-direction: column;
    gap: 8px;
    font-size: 14px;
    color: #e2e8f0;
}

.footer-form-field-full {
    grid-column: 1 / -1;
}

.footer-form-field span {
    font-weight: 600;
    color: #f8fafc;
}

.footer-form-field input,
.footer-form-field textarea {
    border: 1px solid rgba(148, 163, 184, 0.25);
    border-radius: 8px;
    padding: 12px 14px;
    font-size: 15px;
    transition: border-color 0.2s ease, box-shadow 0.2s ease;
    background: rgba(15, 23, 42, 0.25);
    color: #f8fafc;
}

.footer-form-field input::placeholder,
.footer-form-field textarea::placeholder {
    color: rgba(226, 232, 240, 0.55);
}

.footer-form-field input:focus,
.footer-form-field textarea:focus {
    outline: none;
    border-color: #38bdf8;
    box-shadow: 0 0 0 2px rgba(56, 189, 248, 0.25);
    background: rgba(15, 23, 42, 0.35);
}

.footer-form-field textarea {
    resize: vertical;
    min-height: 120px;
}

.footer-form-submit {
    align-self: flex-start;
    background-color: #2563eb;
    color: #ffffff;
    border: none;
    border-radius: 999px;
    padding: 12px 28px;
    font-size: 15px;
    font-weight: 600;
    cursor: pointer;
    transition: background-color 0.2s ease, transform 0.2s ease;
}

.footer-form-submit:hover {
    background-color: #1d4ed8;
    transform: translateY(-1px);
}

.footer-form-submit:active {
    transform: translateY(0);
}

.footer-form-response {
    font-size: 14px;
    margin: 0;
    color: #94a3b8;
}

.footer-form-response--success {
    color: #34d399;
}

.footer-form-response--error {
    color: #f87171;
}

@media (max-width: 960px) {
    .footer-contact-wrapper {
        gap: 24px;
        padding: 0 16px 24px;
    }

    .footer-contact-panel {
        grid-template-columns: 1fr;
        gap: 20px;
    }

    .footer-contact-panel > * {
        padding: 20px;
    }

    .footer-form-grid {
        grid-template-columns: 1fr;
    }

    .footer-form-submit {
        width: 100%;
        text-align: center;
    }
}

@media (prefers-color-scheme: dark) {
    .footer-contact-panel > * {
        background: rgba(15, 23, 42, 0.45);
        border-color: rgba(148, 163, 184, 0.25);
    }

    .footer-form-field input,
    .footer-form-field textarea {
        background: rgba(15, 23, 42, 0.4);
        border-color: rgba(100, 116, 139, 0.4);
    }

    .footer-form-field input:focus,
    .footer-form-field textarea:focus {
        background: rgba(15, 23, 42, 0.5);
    }
}