/* ===========================================================================
   全站导航下拉：产品中心 / 暖通资讯 / 施工案例
   独立文件，避免动 style.css 的缓存；新文件名无历史缓存。
   =========================================================================== */
.rightnav ul li.has-sub { position: relative; }
.rightnav ul li.has-sub > a > .caret {
    display: inline-block;
    margin-left: 5px;
    font-size: 9px;
    line-height: 1;
    color: #b0b0b0;
    vertical-align: 2px;
}

.subnav {
    display: none;
    position: absolute;
    left: 0;
    top: 100%;
    width: 188px;
    padding: 6px 0;
    background: #ffffff;
    border: 1px solid #e6e6e6;
    border-top: 2px solid #d40003;
    box-shadow: 0 10px 24px rgba(0, 0, 0, 0.08);
    z-index: 120;
}

.rightnav ul li .subnav a {
    display: block;
    padding: 0 18px;
    line-height: 40px;
    font-size: 14px;
    color: #444444;
    text-decoration: none;
    white-space: nowrap;
    border-bottom: 0;
    background: none;
}
.rightnav ul li .subnav a:first-child {
    color: #d40003;
    font-weight: bold;
    border-bottom: 1px solid #f0f0f0;
    margin-bottom: 4px;
}

@media screen and (max-width: 1023px) {
    /* 抽屉内容可能超出视口（展开了子菜单时），允许内部滚动 */
    .rightnav { overflow-y: auto; -webkit-overflow-scrolling: touch; }
    .rightnav ul li.on.has-sub > a > .caret { color: #d40003; }
    .rightnav ul li.has-sub { position: static; }
    .rightnav ul li.has-sub > a > .caret {
        display: inline-block;
        margin-left: 0.14rem;
        font-size: 0.18rem;
        line-height: 1;
        color: #b0b0b0;
        vertical-align: 0.02rem;
        transition: transform 0.2s;
    }
    .rightnav ul li.has-sub.open > a > .caret {
        color: #d40003;
        transform: rotate(180deg);
    }
    .rightnav ul li .subnav {
        display: none;
        position: static;
        width: auto;
        padding: 0 0 0.12rem 0.36rem;
        border: 0;
        box-shadow: none;
        background: transparent;
    }
    .rightnav ul li.has-sub.open > .subnav { display: block; }
    .rightnav ul li .subnav a {
        padding: 0;
        line-height: 0.64rem;
        font-size: 0.22rem;
        color: #777777;
    }
    .rightnav ul li .subnav a:first-child {
        color: #777777;
        font-weight: normal;
        border-bottom: 0;
        margin-bottom: 0;
    }
    /* 触摸后残留的 hover 不要给子项留灰底 */
    .rightnav ul li .subnav a:hover { background: none; color: #777777; }
}

/* 头部容器默认 overflow:hidden（用于包住浮动的 logo 与导航），会把绝对定位的下拉面板裁掉。
   桌面端改 visible 并用固定高度撑住，移动端不动（抽屉布局不依赖下拉）。 */
@media screen and (min-width: 1024px) {
    .headerbox { overflow: visible; height: 1.1rem; }
    /* hover 展开只给有鼠标的设备。触摸设备点击后 li 会长期停留在 :hover 状态，
       若沿用这条规则，JS 把 .open 去掉后 :hover 仍然命中，面板就收不起来。 */
    .rightnav ul li.has-sub:hover > a > .caret { color: #d40003; }
    .rightnav ul li.has-sub:hover > .subnav { display: block; }
    .rightnav ul li .subnav a:hover { background: #f5f6f7; color: #d40003; }
}