/* 首页样式 */

/* 导航栏 */
.header {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    z-index: 1000;
    padding: 30px 0;
    transition: all 0.3s ease;
    background: transparent;
    opacity: 0;
    transform: translateY(-100%);
}

.header.scrolled {
    background: #fff;
    border-bottom: 2px solid var(--primary-color);
    padding: 15px 0;
    box-shadow: 0 2px 10px rgba(0, 0, 0, 0.05);
    opacity: 1;
    transform: translateY(0);
}

.header .container {
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.header .logo a {
    display: flex;
    align-items: center;
    gap: 12px;
}

.header .logo-img {
    height: 55px;
    width: auto;
    transition: all 0.3s ease;
}

.header .logo-text-wrapper {
    display: flex;
    flex-direction: column;
    gap: 2px;
    align-items: flex-start;
}

.header .logo-text {
    font-size: 24px;
    font-weight: bold;
    color: #fff;
    transition: color 0.3s ease;
    line-height: 1.2;
}

.header .logo-text-en {
    font-size: 11px;
    font-weight: 500;
    color: rgba(255, 255, 255, 0.8);
    transition: color 0.3s ease;
    letter-spacing: 1px;
    line-height: 1;
    padding-left: 10px;
}

.header.scrolled .logo-text {
    color: var(--primary-color);
}

.header.scrolled .logo-text-en {
    color: rgba(26, 58, 107, 0.7);
}

.header .nav {
    display: flex;
    gap: 30px;
}

.header .nav a {
    color: #fff;
    font-size: 16px;
    position: relative;
    transition: color 0.3s ease;
}

.header.scrolled .nav a {
    color: var(--text-dark);
}

.header .nav a::after {
    content: '';
    position: absolute;
    bottom: -5px;
    left: 0;
    width: 0;
    height: 2px;
    background: #fff;
    transition: width 0.3s ease;
}

.header.scrolled .nav a::after {
    background: var(--primary-color);
}

.header .nav a:hover::after {
    width: 100%;
}

.menu-toggle {
    display: none;
    flex-direction: column;
    gap: 5px;
    cursor: pointer;
}

.menu-toggle span {
    width: 25px;
    height: 3px;
    background: #fff;
    transition: all 0.3s ease;
}

.header.scrolled .menu-toggle span {
    background: var(--primary-color);
}

/* 侧边导航 */
.side-nav {
    position: fixed;
    right: 50px;
    top: 50%;
    transform: translateY(-50%);
    z-index: 100;
}

.side-nav li {
    width: 8px;
    height: 8px;
    border-radius: 50%;
    background: #555;
    margin: 15px 0;
    cursor: pointer;
    transition: all 0.3s ease;
    position: relative;
}

.side-nav li span {
    position: absolute;
    right: 25px;
    top: 50%;
    transform: translateY(-50%);
    white-space: nowrap;
    background: var(--primary-color);
    color: white;
    padding: 5px 15px;
    border-radius: 4px;
    font-size: 14px;
    opacity: 0;
    visibility: hidden;
    transition: all 0.3s ease;
}

.side-nav li:hover span,
.side-nav li.active span {
    opacity: 1;
    visibility: visible;
    right: 30px;
}

.side-nav li.active {
    width: 0;
    height: 0;
}

.side-nav li.active span {
    opacity: 1;
    visibility: visible;
    right: 25px;
}

/* 首屏 Banner */
.banner {
    height: 100vh;
    min-height: 600px;
    width: 100%;
    position: relative;
    display: flex;
    align-items: center;
    justify-content: center;
    background: url('../images/leifengta.jpg') center bottom no-repeat;
    background-size: cover;
    overflow: hidden;
}

/* Banner Logo */
.banner-logo {
    position: absolute;
    top: 40px;
    left: 40px;
    z-index: 10;
    display: flex;
    align-items: center;
    gap: 20px;
    animation: fadeInLeft 1.2s ease-out;
}

.banner-logo img {
    height: 120px;
    width: auto;
    opacity: 0.95;
    animation: logoFloat 3s ease-in-out infinite;
}

.banner-logo-text {
    display: flex;
    gap: 20px;
}

.banner-logo-text span {
    font-family: 'STKaiti', 'KaiTi', serif;
    font-size: 34px;
    font-weight: 600;
    color: #ffffff;
    letter-spacing: 4px;
    text-shadow: 
        2px 2px 4px rgba(0, 0, 0, 0.6),
        0 0 20px rgba(0, 0, 0, 0.4);
    opacity: 0;
    animation: fadeInText 1s ease-out forwards;
}

.banner-logo-text span:first-child {
    animation-delay: 0.5s;
}

.banner-logo-text span:last-child {
    animation-delay: 0.8s;
}

@keyframes fadeInLeft {
    from {
        opacity: 0;
        transform: translateX(-50px);
    }
    to {
        opacity: 1;
        transform: translateX(0);
    }
}

@keyframes fadeInText {
    from {
        opacity: 0;
        transform: translateY(20px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

@keyframes logoFloat {
    0%, 100% {
        transform: translateY(0);
    }
    50% {
        transform: translateY(-10px);
    }
}

/* Banner Slogan */
.banner-slogan {
    position: absolute;
    bottom: 62%;
    left: 49%;
    transform: translateX(-50%);
    z-index: 10;
    text-align: center;
    display: none;  /* 隐藏 slogan */
}

.slogan-text {
    font-family: 'HYShangWeiShouShuW', 'Source Han Serif CN', 'Noto Serif SC', 'STKaiti', 'KaiTi', serif;
    font-size: 120px;
    font-weight: 500;
    color: #ffffff;
    letter-spacing: 12px;
    text-shadow: 
        2px 2px 4px rgba(0, 0, 0, 0.6),
        0 0 20px rgba(0, 0, 0, 0.4),
        0 0 40px rgba(0, 0, 0, 0.2);
    margin: 0;
    white-space: nowrap;
    animation: fadeInUp 1.5s ease-out;
}

.slogan-part {
    display: inline-block;
}

.slogan-part:first-child {
    margin-right: 140px;
}

@keyframes fadeInUp {
    from {
        opacity: 0;
        transform: translateY(30px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

/* 粒子漂浮效果 */
.particles {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    overflow: hidden;
    pointer-events: none;
}

.particle {
    position: absolute;
    width: 4px;
    height: 4px;
    background: rgba(205, 175, 104, 0.6);
    border-radius: 50%;
    box-shadow: 0 0 10px rgba(205, 175, 104, 0.3);
    animation: float linear infinite;
}

.particle:nth-child(1) { left: 10%; animation-duration: 15s; animation-delay: 0s; }
.particle:nth-child(2) { left: 20%; animation-duration: 18s; animation-delay: 2s; }
.particle:nth-child(3) { left: 30%; animation-duration: 20s; animation-delay: 4s; }
.particle:nth-child(4) { left: 40%; animation-duration: 16s; animation-delay: 1s; }
.particle:nth-child(5) { left: 50%; animation-duration: 22s; animation-delay: 3s; }
.particle:nth-child(6) { left: 60%; animation-duration: 19s; animation-delay: 5s; }
.particle:nth-child(7) { left: 70%; animation-duration: 17s; animation-delay: 2s; }
.particle:nth-child(8) { left: 80%; animation-duration: 21s; animation-delay: 4s; }
.particle:nth-child(9) { left: 90%; animation-duration: 18s; animation-delay: 1s; }
.particle:nth-child(10) { left: 15%; animation-duration: 20s; animation-delay: 3s; }
.particle:nth-child(11) { left: 25%; animation-duration: 16s; animation-delay: 5s; }
.particle:nth-child(12) { left: 35%; animation-duration: 19s; animation-delay: 2s; }
.particle:nth-child(13) { left: 45%; animation-duration: 17s; animation-delay: 4s; }
.particle:nth-child(14) { left: 55%; animation-duration: 21s; animation-delay: 1s; }
.particle:nth-child(15) { left: 65%; animation-duration: 18s; animation-delay: 3s; }
.particle:nth-child(16) { left: 75%; animation-duration: 20s; animation-delay: 5s; }
.particle:nth-child(17) { left: 85%; animation-duration: 16s; animation-delay: 2s; }
.particle:nth-child(18) { left: 95%; animation-duration: 19s; animation-delay: 4s; }
.particle:nth-child(19) { left: 12%; animation-duration: 22s; animation-delay: 1s; }
.particle:nth-child(20) { left: 88%; animation-duration: 17s; animation-delay: 3s; }

@keyframes float {
    0% {
        transform: translateY(100vh) translateX(0) scale(0);
        opacity: 0;
    }
    10% {
        opacity: 1;
    }
    90% {
        opacity: 1;
    }
    100% {
        transform: translateY(-100px) translateX(100px) scale(1);
        opacity: 0;
    }
}

/* 多层圆环脉冲效果 */
.rings {
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    width: 100%;
    height: 100%;
    pointer-events: none;
}

.ring {
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    border-radius: 50%;
    border: 1px solid rgba(255, 255, 255, 0.15);
}

.ring-1 {
    width: 50%;
    height: 50%;
    animation: ringPulse 6s ease-in-out infinite;
}

.ring-2 {
    width: 65%;
    height: 65%;
    animation: ringPulse 6s ease-in-out infinite 2s;
}

.ring-3 {
    width: 80%;
    height: 80%;
    animation: ringPulse 6s ease-in-out infinite 4s;
}

@keyframes ringPulse {
    0%, 100% {
        transform: translate(-50%, -50%) scale(1);
        opacity: 0.2;
    }
    50% {
        transform: translate(-50%, -50%) scale(1.15);
        opacity: 0.4;
    }
}

@keyframes gradientShift {
    0%, 100% {
        opacity: 1;
    }
    50% {
        opacity: 0.8;
    }
}

.banner-content {
    position: relative;
    z-index: 1;
    text-align: center;
    color: white;
    max-width: 900px;
    padding: 0 20px;
}

.banner-title {
    font-size: 56px;
    font-weight: 300;
    margin-bottom: 20px;
    letter-spacing: 4px;
}

.banner-subtitle {
    font-size: 28px;
    margin-bottom: 20px;
    color: var(--accent-color);
    font-weight: 300;
    letter-spacing: 8px;
}

.banner-desc {
    font-size: 18px;
    margin-bottom: 40px;
    opacity: 0.9;
    line-height: 1.8;
}

.banner-buttons {
    display: flex;
    gap: 20px;
    justify-content: center;
}

.banner-buttons .btn {
    min-width: 160px;
}

/* 关于我们 */
.about {
    background: var(--white);
    padding: 80px 0;
}

.about-content {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 50px;
    margin-bottom: 40px;
}

.about-text p {
    margin-bottom: 20px;
    line-height: 1.8;
    color: var(--text-light);
    text-align: justify;
}

.about-stats {
    display: flex;
    flex-direction: column;
    justify-content: center;
    gap: 40px;
}

.stat-item {
    text-align: center;
}

.stat-item .number {
    display: block;
    font-size: 48px;
    font-weight: bold;
    color: var(--primary-color);
    margin-bottom: 10px;
}

.stat-item .label {
    display: block;
    font-size: 16px;
    color: var(--text-light);
}

.about-images .image-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 20px;
}

.about-images img {
    width: 100%;
    height: 250px;
    object-fit: cover;
    border-radius: 8px;
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.1);
}

/* 业务领域 */
.practices {
    background: var(--bg-light);
    padding: 80px 0;
}

.practices-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 25px;
}

.practice-item {
    background: white;
    padding: 40px 30px;
    border-radius: 12px;
    text-align: center;
    transition: all 0.4s cubic-bezier(0.4, 0, 0.2, 1);
    box-shadow: 0 2px 8px rgba(0, 0, 0, 0.08);
    border: 1px solid transparent;
    position: relative;
    overflow: hidden;
}

.practice-item::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    height: 3px;
    background: linear-gradient(90deg, transparent, var(--accent-color), transparent);
    transform: scaleX(0);
    transition: transform 0.4s ease;
}

.practice-item:hover::before {
    transform: scaleX(1);
}

.practice-item:hover {
    transform: translateY(-10px);
    box-shadow: 0 12px 32px rgba(26, 58, 107, 0.15);
    border-color: rgba(26, 58, 107, 0.1);
}

.practice-item:hover .practice-icon {
    color: var(--primary-color);
    transform: scale(1.1);
}

.practice-icon {
    font-size: 48px;
    margin-bottom: 20px;
    color: var(--accent-color);
    transition: all 0.4s ease;
}

.practice-icon i {
    display: block;
    font-weight: 300;
}

.practice-item h3 {
    font-size: 20px;
    color: var(--text-dark);
    margin-bottom: 15px;
}

.practice-item p {
    color: var(--text-light);
    line-height: 1.6;
}

/* 专业团队 */
.team {
    background: white;
    padding: 80px 0;
}

.team-intro {
    max-width: 900px;
    margin: 0 auto 40px;
    text-align: center;
    color: var(--text-light);
    line-height: 1.8;
}

.team-grid {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 25px;
}

.team-member {
    text-align: center;
    padding: 0;
    background: white;
    border-radius: 12px;
    overflow: hidden;
    transition: all 0.4s cubic-bezier(0.4, 0, 0.2, 1);
    box-shadow: 0 2px 8px rgba(0, 0, 0, 0.08);
    border: 1px solid rgba(0, 0, 0, 0.05);
}

.team-member:hover {
    transform: translateY(-10px) scale(1.02);
    box-shadow: 0 12px 32px rgba(26, 58, 107, 0.15);
    border-color: var(--primary-color);
}

.member-photo {
    width: 100%;
    height: auto;
    margin: 0 auto 20px;
    border-radius: 8px;
    overflow: hidden;
    background: var(--bg-light);
}

.member-photo img {
    width: 100%;
    height: auto;
    display: block;
    object-fit: cover;
}

.photo-placeholder {
    font-size: 60px;
    width: 120px;
    height: 120px;
    margin: 0 auto;
    border-radius: 50%;
    background: var(--primary-color);
    display: flex;
    align-items: center;
    justify-content: center;
}

.team-member h3 {
    font-size: 20px;
    color: var(--text-dark);
    margin-bottom: 8px;
    padding: 0 20px;
}

.team-member .title {
    color: var(--primary-color);
    font-size: 14px;
    margin-bottom: 15px;
    padding: 0 20px;
}

.team-member .desc {
    color: var(--text-light);
    font-size: 14px;
    line-height: 1.6;
    padding: 0 20px 20px;
}

/* 成功案例 */
.cases {
    background: var(--bg-light);
}

.cases-list {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 25px;
}

.case-item {
    background: white;
    padding: 40px;
    border-radius: 12px;
    border-left: 4px solid var(--primary-color);
    transition: all 0.4s cubic-bezier(0.4, 0, 0.2, 1);
    box-shadow: 0 2px 8px rgba(0, 0, 0, 0.05);
    position: relative;
}

.case-item::after {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    border-radius: 12px;
    border: 1px solid transparent;
    transition: border-color 0.4s ease;
    pointer-events: none;
}

.case-item:hover {
    box-shadow: 0 12px 32px rgba(26, 58, 107, 0.12);
    transform: translateX(8px);
    border-left-color: var(--accent-color);
}

.case-item:hover::after {
    border-color: rgba(26, 58, 107, 0.1);
}

.case-tag {
    display: inline-block;
    background: var(--primary-color);
    color: white;
    padding: 5px 15px;
    border-radius: 20px;
    font-size: 12px;
    margin-bottom: 15px;
}

.case-item h3 {
    font-size: 22px;
    color: var(--text-dark);
    margin-bottom: 15px;
}

.case-desc {
    color: var(--text-light);
    line-height: 1.8;
    margin-bottom: 20px;
}

.case-result {
    color: var(--accent-color);
    font-weight: bold;
}

/* 荣誉展示 */
.honors {
    background: white;
}

.honors-grid {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 20px;
    margin-bottom: 40px;
}

.honor-item {
    background: white;
    padding: 15px;
    border-radius: 12px;
    overflow: hidden;
    box-shadow: 0 2px 8px rgba(0, 0, 0, 0.08);
    border: 1px solid rgba(0, 0, 0, 0.05);
    transition: all 0.3s ease;
}

.honor-item:hover {
    box-shadow: 0 8px 20px rgba(26, 58, 107, 0.12);
    transform: translateY(-5px);
}

.honor-item img {
    width: 100%;
    height: 300px;
    object-fit: cover;
    border-radius: 8px;
    transition: transform 0.4s ease;
}

.honor-item:hover img {
    transform: scale(1.05);
}

.honors-flags h3 {
    text-align: center;
    font-size: 28px;
    color: var(--text-dark);
    margin-bottom: 30px;
}

.flags-grid {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 30px;
}

.flags-grid img {
    width: 100%;
    height: 250px;
    object-fit: cover;
    border-radius: 12px;
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.1);
    border: 1px solid rgba(0, 0, 0, 0.05);
    transition: all 0.3s ease;
}

.flags-grid img:hover {
    transform: translateY(-5px);
    box-shadow: 0 8px 20px rgba(26, 58, 107, 0.15);
}

/* 新闻动态 */
.news {
    background: var(--bg-light);
}

.news-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 25px;
}

.news-item {
    background: white;
    border-radius: 12px;
    overflow: hidden;
    transition: all 0.4s cubic-bezier(0.4, 0, 0.2, 1);
    box-shadow: 0 2px 8px rgba(0, 0, 0, 0.08);
    border: 1px solid rgba(0, 0, 0, 0.05);
}

.news-item:hover {
    transform: translateY(-10px);
    box-shadow: 0 12px 32px rgba(26, 58, 107, 0.15);
    border-color: var(--primary-color);
}

.news-image {
    width: 100%;
    height: 220px;
    overflow: hidden;
}

.news-image img {
    width: 100%;
    height: 100%;
    object-fit: cover;
    transition: transform 0.3s ease;
}

.news-item:hover .news-image img {
    transform: scale(1.1);
}

.news-content {
    padding: 25px;
}

.news-content .date {
    display: block;
    color: var(--primary-color);
    font-size: 14px;
    margin-bottom: 10px;
}

.news-content h3 {
    font-size: 18px;
    color: var(--text-dark);
    margin-bottom: 15px;
    line-height: 1.4;
}

.news-content p {
    color: var(--text-light);
    line-height: 1.6;
    font-size: 14px;
}

/* 办公环境 */
.office {
    background: white;
}

.office-swiper {
    position: relative;
    padding: 0 60px;
}

.office-swiper .swiper-slide {
    text-align: center;
}

.office-swiper img {
    width: 100%;
    height: 500px;
    object-fit: cover;
    border-radius: 8px;
    margin-bottom: 20px;
}

.office-swiper p {
    font-size: 18px;
    color: var(--text-dark);
}

.swiper-button-prev,
.swiper-button-next {
    color: var(--primary-color);
}

.swiper-pagination-bullet-active {
    background: var(--primary-color);
}

/* 联系我们 */
.contact {
    background: var(--bg-light);
}

.contact-content {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 40px;
}

.contact-info {
    display: flex;
    flex-direction: column;
    gap: 30px;
}

.info-item {
    display: flex;
    gap: 20px;
    padding: 25px;
    background: white;
    border-radius: 12px;
    box-shadow: 0 2px 8px rgba(0, 0, 0, 0.05);
    border: 1px solid rgba(0, 0, 0, 0.05);
    transition: all 0.3s ease;
}

.info-item:hover {
    box-shadow: 0 8px 20px rgba(26, 58, 107, 0.1);
    border-color: var(--primary-color);
    transform: translateX(5px);
}

.info-icon {
    font-size: 32px;
    flex-shrink: 0;
}

.info-text h4 {
    font-size: 18px;
    color: var(--text-dark);
    margin-bottom: 8px;
}

.info-text p {
    color: var(--text-light);
    line-height: 1.6;
}

.contact-form {
    background: white;
    padding: 40px;
    border-radius: 12px;
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.1);
    border: 1px solid rgba(0, 0, 0, 0.05);
}

.contact-form h3 {
    font-size: 24px;
    color: var(--text-dark);
    margin-bottom: 30px;
}

.contact-form input,
.contact-form textarea {
    width: 100%;
    padding: 15px;
    margin-bottom: 20px;
    border: 1px solid #ddd;
    border-radius: 4px;
    font-size: 14px;
    transition: border-color 0.3s ease;
}

.contact-form input:focus,
.contact-form textarea:focus {
    border-color: var(--primary-color);
    outline: none;
}

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

.contact-form button {
    width: 100%;
    padding: 15px;
    background: linear-gradient(135deg, var(--primary-color), var(--secondary-color));
    color: white;
    border: none;
    border-radius: 8px;
    font-size: 16px;
    font-weight: bold;
    cursor: pointer;
    transition: all 0.3s ease;
    position: relative;
    overflow: hidden;
}

.contact-form button::before {
    content: '';
    position: absolute;
    top: 0;
    left: -100%;
    width: 100%;
    height: 100%;
    background: linear-gradient(90deg, transparent, rgba(255, 255, 255, 0.2), transparent);
    transition: left 0.5s ease;
}

.contact-form button:hover::before {
    left: 100%;
}

.contact-form button:hover {
    transform: translateY(-2px);
    box-shadow: 0 6px 20px rgba(26, 58, 107, 0.3);
}

/* 页脚 */
.footer {
    background: #323232;
    color: white;
    padding: 50px 0 30px;
    position: relative;
}

.footer::before {
    content: '';
    position: absolute;
    top: 0;
    left: 50%;
    transform: translateX(-50%);
    width: 80%;
    height: 1px;
    background: linear-gradient(90deg, transparent, var(--accent-color), transparent);
}

.footer-content {
    display: grid;
    grid-template-columns: 2fr 1fr;
    gap: 40px;
    margin-bottom: 30px;
}

.footer-logo-section {
    display: flex;
    align-items: flex-start;
    gap: 15px;
    margin-bottom: 20px;
}

.footer-logo-img {
    height: 80px;
    width: auto;
    flex-shrink: 0;
    /* background-color: #333333; */
}

.footer-text-wrapper {
    display: flex;
    flex-direction: column;
    padding-top:12px;
    gap: 5px;
}

.footer-title {
    font-size: 24px;
    margin: 0;
    line-height: 1.2;
}

.footer-title-en {
    font-size: 13px;
    opacity: 0.85;
    letter-spacing: 1.5px;
    margin: 0;
    font-weight: 400;
}

.footer-slogan {
    margin-bottom: 20px;
    opacity: 0.9;
    font-size: 15px;
    font-style: italic;
}

.footer-info p {
    margin-bottom: 10px;
    opacity: 0.9;
}

.footer-contact {
    margin-top: 20px;
}

.footer-contact p {
    margin-bottom: 10px;
}

.footer-links h4 {
    font-size: 18px;
    margin-bottom: 20px;
}

.footer-links a {
    display: block;
    margin-bottom: 10px;
    opacity: 0.8;
    transition: opacity 0.3s ease;
}

.footer-links a:hover {
    opacity: 1;
}

.footer-bottom {
    text-align: center;
    padding-top: 30px;
    border-top: 1px solid rgba(205, 175, 104, 0.2);
    opacity: 0.8;
}

/* 返回顶部 */
.back-to-top {
    position: fixed;
    right: 30px;
    bottom: 30px;
    width: 50px;
    height: 50px;
    background: var(--primary-color);
    color: white;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 24px;
    cursor: pointer;
    opacity: 0;
    visibility: hidden;
    transition: all 0.3s ease;
    z-index: 999;
}

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

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

/* 响应式设计 */

/* 平板 */
@media (max-width: 1199px) {
    .section {
        padding: 60px 0;
    }
    
    .about,
    .team,
    .practices {
        padding: 60px 0;
    }
    
    .section-title {
        margin-bottom: 40px;
    }
    
    .section-title h2 {
        font-size: 32px;
    }
    
    .banner h1 {
        font-size: 40px;
    }
    
    .about-content {
        gap: 40px;
    }
    
    .practices-grid {
        grid-template-columns: repeat(2, 1fr);
    }
    
    .team-grid {
        grid-template-columns: repeat(3, 1fr);
    }
    
    .honors-grid,
    .flags-grid {
        grid-template-columns: repeat(3, 1fr);
    }
    
    .side-nav {
        right: 30px;
    }
}

/* 手机 */
@media (max-width: 767px) {
    .section {
        padding: 50px 0;
    }
    
    .about,
    .team,
    .practices {
        padding: 50px 0;
    }
    
    .section-title {
        margin-bottom: 30px;
    }
    
    .section-title h2 {
        font-size: 28px;
    }
    
    .header .nav {
        position: fixed;
        top: 0;
        right: -100%;
        width: 80%;
        height: 100vh;
        background: white;
        flex-direction: column;
        padding: 80px 30px;
        gap: 20px;
        box-shadow: -2px 0 10px rgba(0, 0, 0, 0.1);
        transition: right 0.3s ease;
    }
    
    .header .nav.active {
        right: 0;
    }
    
    .menu-toggle {
        display: flex;
    }
    
    .menu-toggle.active span:nth-child(1) {
        transform: rotate(45deg) translate(5px, 5px);
    }
    
    .menu-toggle.active span:nth-child(2) {
        opacity: 0;
    }
    
    .menu-toggle.active span:nth-child(3) {
        transform: rotate(-45deg) translate(7px, -7px);
    }
    
    .banner {
        min-height: 500px;
    }
    
    .banner-title {
        font-size: 32px !important;
        letter-spacing: 2px !important;
    }
    
    .banner-subtitle {
        font-size: 18px !important;
        letter-spacing: 4px !important;
    }
    
    .banner-desc {
        font-size: 14px !important;
    }
    
    .banner-buttons {
        flex-direction: column;
        gap: 15px !important;
    }
    
    .banner-buttons .btn {
        width: 100%;
    }
    
    .about-content {
        grid-template-columns: 1fr;
        gap: 30px;
    }
    
    .about-images .image-grid {
        grid-template-columns: 1fr;
    }
    
    .practices-grid {
        grid-template-columns: 1fr;
    }
    
    .team-grid {
        grid-template-columns: 1fr;
    }
    
    .cases-list {
        grid-template-columns: 1fr;
    }
    
    .honors-grid,
    .flags-grid {
        grid-template-columns: repeat(2, 1fr);
        gap: 15px;
    }
    
    .news-grid {
        grid-template-columns: 1fr;
    }
    
    .contact-content {
        grid-template-columns: 1fr;
        gap: 30px;
    }
    
    .footer-content {
        grid-template-columns: 1fr;
        gap: 30px;
    }
    
    .side-nav {
        display: none;
    }
    
    .office-swiper {
        padding: 0;
    }
    
    .office-swiper img {
        height: 300px;
    }
}