/* 顶部条 - 高级深色金属感 */
.head_top {
    height: 44px;
    background: radial-gradient(circle at center, #FE3303, #CC2802, #991E01);
    position: relative;
    z-index: 10;
    border-bottom: 1px solid rgba(255, 255, 255, 0.08);
}

.head_top .head_top_box {
    max-width: 1440px;
    width: 90%;
    margin: 0 auto;
    height: 100%;
    display: flex;
    align-items: center;
    justify-content: space-between;
}

.head_top .head_top_box .head_top_location p {
    color: #fff;
    font-size: 13px;
    font-weight: 400;
    letter-spacing: 0.3px;
    background: url('data:image/svg+xml;utf8,<svg xmlns="http://www.w3.org/2000/svg" width="14" height="14" viewBox="0 0 24 24" fill="none" stroke="%23d4af37" stroke-width="1.5" stroke-linecap="round" stroke-linejoin="round"><path d="M21 10c0 7-9 13-9 13s-9-6-9-13a9 9 0 0 1 18 0z"></path><circle cx="12" cy="10" r="3"></circle></svg>') no-repeat left center;
    background-size: 14px;
    padding-left: 20px;
}

.head_top .head_top_box .head_top_nav {
    display: flex;
    align-items: center;
    gap: 8px;
    flex-wrap: wrap;
    font-size: 13px;
    color: #fff;
}

.head_top .head_top_box .head_top_nav a {
    color: #fff;
    text-decoration: none;
    font-size: 13px;
    transition: all 0.25s ease;
    padding: 0 12px;
    position: relative;
    letter-spacing: 0.2px;
}

.head_top .head_top_box .head_top_nav a:hover {
    color: #FE3303;
}

.head_top .head_top_box .head_top_nav a:not(:last-child)::after {
    content: '';
    position: absolute;
    right: 0;
    top: 50%;
    transform: translateY(-50%);
    width: 1px;
    height: 12px;
    background: rgba(255,255,255,0.2);
}

.head_top .head_top_box .head_top_tel {
    margin-left: 20px;
    font-weight: 400;
    background: rgba(0,0,0,0.2);
    padding: 4px 14px;
    border-radius: 40px;
    backdrop-filter: blur(2px);
}

.head_top .head_top_box .head_top_tel b {
    color: #fff;
    font-weight: 600;
    margin-left: 6px;
    font-size: 14px;
}

/* 主头部 - 高级商务 */
header {
    height: 80px;
    background: #ffffff;
    box-shadow: 0 8px 28px -6px rgba(0, 0, 0, 0.06);
    transition: all 0.3s cubic-bezier(0.2, 0, 0, 1);
    position: relative;
    z-index: 20;
}

header.fixed {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    background: rgba(255,255,255,0.98);
    backdrop-filter: blur(8px);
    box-shadow: 0 12px 32px -12px rgba(0, 0, 0, 0.12);
    animation: fadeDown 0.3s ease;
}

@keyframes fadeDown {
    from {
        opacity: 0;
        transform: translateY(-12px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

.head_box {
    max-width: 1440px;
    width: 90%;
    margin: 0 auto;
    height: 100%;
    display: flex;
    align-items: center;
    justify-content: space-between;
}

/* LOGO区域 */
.head_box_logo {
    display: flex;
    align-items: center;
    text-decoration: none;
    height: 56px;
    transition: opacity 0.2s;
}

.head_box_logo:hover {
    opacity: 0.92;
}

.head_box_logo img {
    max-height: 100%;
    width: auto;
    object-fit: contain;
    filter: drop-shadow(0 2px 4px rgba(0,0,0,0.02));
}

/* 导航菜单 */
.head_nav {
    display: flex;
    align-items: center;
    height: 100%;
    gap: 8px;
}

.head_nav_ul {
    display: flex;
    align-items: center;
    height: 100%;
    gap: 6px;
}

.nav_ul_li {
    height: 100%;
    display: flex;
    align-items: center;
    position: relative;
}

.nav_ul_li a {
    padding: 0 12px;
    font-size: 15px;
    font-weight: 500;
    color: #23262b;
    text-decoration: none;
    letter-spacing: 0.3px;
    transition: all 0.2s;
    white-space: nowrap;
    display: inline-flex;
    align-items: center;
    height: 100%;
    position: relative;
}

/* 下划线动画 */
.nav_ul_li a::after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 50%;
    width: 0;
    height: 2px;
    background: #FE3303;
    transition: all 0.25s ease;
    transform: translateX(-50%);
}

.nav_ul_li a:hover::after,
.nav_ul_li.attr a::after {
    width: 70%;
}

.nav_ul_li a:hover {
    color: #FE3303;
}

.nav_ul_li.attr a {
    color: #FE3303;
    font-weight: 600;
}

/* 搜索框高级感 */
.top_input {
    width: 240px;
    height: 42px;
    position: relative;
    border: 1px solid #e2e6ef;
    border-radius: 60px;
    background: #ffffff;
    transition: all 0.2s;
    box-shadow: 0 1px 2px rgba(0,0,0,0.02);
}

.top_input:focus-within {
    border-color: #FE3303;
    box-shadow: 0 0 0 3px rgba(212, 175, 55, 0.1);
}

.top_input input {
    width: 100%;
    height: 100%;
    background: transparent;
    outline: none;
    border: none;
    padding: 0 20px 0 20px;
    font-size: 14px;
    color: #1f2a3e;
    border-radius: 60px;
}

.top_input input::placeholder {
    color: #9aa4b8;
    font-weight: 400;
}

.top_input .top_input_btn {
    position: absolute;
    right: 6px;
    top: 50%;
    transform: translateY(-50%);
    width: 32px;
    height: 32px;
    background: url('data:image/svg+xml;utf8,<svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 24 24" fill="none" stroke="%23818c9e" stroke-width="1.6" stroke-linecap="round" stroke-linejoin="round"><circle cx="11" cy="11" r="8"></circle><line x1="21" y1="21" x2="16.65" y2="16.65"></line></svg>') no-repeat center;
    background-size: 18px;
    cursor: pointer;
    transition: 0.2s;
    opacity: 0.7;
}

.top_input .top_input_btn:hover {
    opacity: 1;
    background-image: url('data:image/svg+xml;utf8,<svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 24 24" fill="none" stroke="%23d4af37" stroke-width="1.8" stroke-linecap="round" stroke-linejoin="round"><circle cx="11" cy="11" r="8"></circle><line x1="21" y1="21" x2="16.65" y2="16.65"></line></svg>');
}

/* 移动端按钮 */
.head_box_list_btn {
    display: none;
}

.head_box_zz {
    height: 80px;
    display: none;
}

.head_box_zz.active {
    display: block;
}

/* ========= 响应式高端商务处理 ========= */
@media screen and (max-width: 1300px) {
    .head_nav_ul .nav_ul_li a {
        padding: 0 12px;
        font-size: 14px;
    }
    .top_input {
        width: 200px;
    }
}

@media screen and (max-width: 1150px) {
    .head_nav_ul .nav_ul_li a {
        padding: 0 10px;
        font-size: 13px;
    }
    .top_input {
        width: 180px;
    }
}

@media screen and (max-width: 992px) {
    .head_nav {
        gap: 0;
    }
    .top_input {
        display: none;  /* 平板时隐藏搜索，让导航更舒展 */
    }
    .head_nav_ul .nav_ul_li a {
        padding: 0 12px;
        font-size: 14px;
    }
}

@media screen and (max-width: 768px) {
    header {
        position: fixed;
        top: 0;
        left: 0;
        width: 100%;
        z-index: 30;
        height: 70px;
        background: white;
    }
    .head_top {
        display: none !important;
    }
    .head_box_zz {
        height: 70px;
        display: block;
    }
    .head_box {
        justify-content: space-between;
        width: 92%;
    }
    .head_nav {
        display: none;
        position: fixed;
        top: 70px;
        left: 0;
        width: 100%;
        background: rgba(255,255,255,0.98);
        backdrop-filter: blur(12px);
        flex-direction: column;
        align-items: flex-start;
        padding: 20px 24px;
        box-shadow: 0 20px 30px -12px rgba(0,0,0,0.1);
        border-top: 1px solid #efefef;
        z-index: 40;
        box-sizing: border-box;
    }
    .head_nav_ul {
        flex-direction: column;
        width: 100%;
        gap: 12px;
        height: auto;
    }
    .nav_ul_li {
        width: 100%;
        height: auto;
    }
    .nav_ul_li a {
        padding: 12px 0;
        width: 100%;
        font-size: 18px;
        font-weight: 500;
        justify-content: space-between;
    }
    .nav_ul_li a::after {
        display: none;
    }
    .nav_ul_li.attr a {
        color: #FE3303;
        border-left: 3px solid #FE3303;
        padding-left: 15px;
    }
    .top_input {
        display: flex;
        width: 100%;
        margin: 15px 0 5px;
    }
    .head_box_list_btn {
        display: block;
        width: 44px;
        height: 44px;
        background: url('data:image/svg+xml;utf8,<svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 24 24" fill="none" stroke="%23333" stroke-width="1.5" stroke-linecap="round" stroke-linejoin="round"><line x1="3" y1="12" x2="21" y2="12"></line><line x1="3" y1="6" x2="21" y2="6"></line><line x1="3" y1="18" x2="21" y2="18"></line></svg>') no-repeat center;
        background-size: 24px;
        cursor: pointer;
    }
}

/* 演示页面额外样式 (模拟内容) */
.demo-content {
    max-width: 1440px;
    width: 90%;
    margin: 40px auto 100px;
    background: #fff;
    border-radius: 28px;
    box-shadow: 0 20px 40px -12px rgba(0,0,0,0.05);
    padding: 48px 40px;
}
.demo-content h2 {
    font-size: 28px;
    font-weight: 600;
    color: #1a2634;
    margin-bottom: 20px;
    letter-spacing: -0.3px;
}
.demo-content p {
    font-size: 16px;
    line-height: 1.6;
    color: #3e4a5e;
}
@media (max-width: 768px) {
    .demo-content {
        padding: 30px 20px;
        margin-top: 90px;
    }
    .demo-content h2 {
        font-size: 22px;
    }
}