/* 独立的头部样式，不影响页面其他部分 */
.header {
    width: 100%;
    height: 87px;
    background: rgb(30, 30, 30);
    line-height: 85px;
    position: fixed;
    z-index: 1000;
    top: 0;
    left: 0;
}

.header-container {
    width: 1200px;
    height: 100%;
    margin: 0 auto;
    color: #fff;
    display: flex;
    justify-content: space-between;
    align-items: center;
    position: relative;
}

.logo {
    flex: 1;
}

.logo img {
    max-width: 100%;
    height: auto;
    transform: scale(0.8);
}

.nav {
    display: flex;
    align-items: center;
}

.nav ul {
    list-style: none;
    margin: 0px;
    padding: 0px;
    /* display: flex; */
}

.nav ul li {
    display: inline-block;
    font-size: 15px;
    font-weight: 500;
    margin-left: 20px;
}

.nav ul .tcm a {
    color: #fff;
    padding: 8px 18px;
    text-decoration: none;
}

.nav ul .tcm a:hover {
    color: #428bca;
}

/* .header-btn {
    min-width: 150px;
    text-align: center;
    margin-left: 10px;
    font-size: 15px;
    font-family: AvenirLTStd-Medium, Helvetica, Arial, sans-serif;
    letter-spacing: 0.65px;
    text-transform: uppercase;
    padding: 1px;
    border: 2px solid white;
    position: relative;
    display: inline-block;
    border-radius: 30px;
    top: -5px;
    margin-bottom: 0;
    font-weight: normal;
    line-height: 1.428571429;
    white-space: nowrap;
    vertical-align: middle;
    cursor: pointer;
    background-image: none;
} */

.header-btn {
    min-width: 150px;
    text-align: center;
    margin-left: 10px;
    font-size: 15px;
    font-family: AvenirLTStd-Medium, Helvetica, Arial, sans-serif;
    letter-spacing: 0.65px;
    text-transform: uppercase;
    padding: 1px;
    border: 2px solid white;
    position: relative;
    display: inline-block;
    -moz-border-radius: 30px;
    -webkit-border-radius: 30px;
    -o-border-radius: 30px;
    border-radius: 30px;
    top: -5px;
    margin-bottom: 0;
    font-weight: normal;
    line-height: 1.428571429;
    white-space: nowrap;
    vertical-align: middle;
    cursor: pointer;
    background-image: none;
}

/* .header-btn a {
    border: 3px solid rgb(30, 30, 30);
    border-radius: 30px;
    padding: 8px 18px;
    text-shadow: 0 1px 0 rgba(255, 255, 255, 0.25);
    line-height: 20px;
    color: #fff;
    position: relative;
    display: block;
    text-decoration: none;
} */

.header-btn a {
    border: 3px solid rgb(30, 30, 30);
    border-radius: 30px;
    padding: 8px 18px;
    text-shadow: 0 1px 0 rgba(255, 255, 255, 0.25);
    line-height: 20px;
    color: #fff;
    position: relative;
    display: block;
}

.header-btn a:hover {
    border-radius: 30px;
    border: 3px solid rgb(30, 30, 30);
    color: black;
    text-decoration: none;
}

.header-btn:hover {
    background: #fff;
    border: 2px solid #fff;
    color: black;
}

.menu-toggle {
    display: none;
    color: #fff;
    font-size: 24px;
    cursor: pointer;
}

/* 导航栏动画 */
@keyframes fadeInDown {
    from {
        opacity: 0;
        transform: translateY(-10px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

/* 全屏遮盖层 */
.overlay {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: rgba(0, 0, 0, 0.7);
    z-index: 998;
    display: none;
    opacity: 0;
    transition: opacity 0.3s ease;
}

.overlay.show {
    display: block;
    opacity: 1;
}

/* 平板设备响应式 */
@media screen and (min-width: 768px) and (max-width: 1024px) {
    .header-container {
        padding: 0 15px;
        width: 100%;
    }
    
    .nav ul li {
        margin-left: 15px;
    }
    
    .nav ul li a {
        font-size: 14px;
        padding: 6px 15px;
    }
    
    .header-btn {
        min-width: 130px;
        font-size: 14px;
    }
    
    .header-btn a {
        padding: 6px 15px;
    }
}

/* 手机设备响应式 */
@media screen and (max-width: 767px) {
    .header {
        height: 60px;
        line-height: 60px;
    }
    
    .header-container {
        padding: 0 10px;
        width: 100%;
    }
    
    .logo {
        width: 150px;
    }
    
    .logo img {
        transform: scale(0.7);
    }
    
    .menu-toggle {
        display: block;
    }
    
    .nav {
        display: none;
        position: fixed;
        top: 60px;
        left: 0;
        width: 100%;
        height: calc(100vh - 60px);
        background: rgba(30, 30, 30, 0.7);
        flex-direction: column;
        padding: 10px 0;
        box-shadow: 0 4px 6px rgba(0, 0, 0, 0.1);
        overflow-y: auto;
        z-index: 999;
    }
    
    .nav.open {
        display: flex;
    }
    
    /* 防止页面滚动 */
    body.nav-open {
        overflow: hidden;
    }
    
    .nav ul {
        flex-direction: column;
        width: 100%;
    }
    
    .nav ul li {
        margin: 5px 0;
        text-align: center;
        width: 100%;
    }
    
    .nav ul li a {
        display: block;
        padding: 12px 0;
        font-size: 16px;
    }
    
    .header-btn {
        width: 90%;
        margin: 10px auto;
        min-width: auto;
    }
    
    .header-btn a {
        padding: 10px 0;
    }
}

/* 超小屏幕设备 */
@media screen and (max-width: 480px) {
    .header-container {
        padding: 0 5px;
    }
    
    .logo {
        width: 120px;
    }
    
    .nav ul li a {
        font-size: 14px;
        padding: 8px 0;
    }
}