/* ============================================================
   复盛空压机 · 产品官网样式
   设计基准：深藏青工业蓝 + 复盛红点缀，宽屏专业风
   ============================================================ */

:root {
    --navy: #0e2a47;
    --navy-2: #16395e;
    --navy-3: #1b4b7d;
    --blue: #1f6fb2;
    --blue-light: #e8f1fa;
    --red: #c8102e;
    --red-dark: #a30d25;
    --text: #1a1f2b;
    --text-2: #5a6478;
    --text-3: #8b95a8;
    --line: #e2e7ef;
    --bg: #ffffff;
    --bg-soft: #f4f6f9;
    --bg-soft2: #eaeef5;
    --shadow: 0 2px 8px rgba(14, 42, 71, .06);
    --shadow-lg: 0 12px 32px rgba(14, 42, 71, .12);
    --radius: 6px;
    --wrap: 1280px;
    /* 导航项左右内边距，窄屏逐级收紧（下划线宽度跟随它）。
       11px 是量出来的上限：chevron 箭头（gap 5px + 7px 宽）已让 6 个带下拉的
       一级项累计增宽约 120px，再大就会在 1440px 下把 header 撑出横向滚动。 */
    --nav-pad: 11px;
    /* 全站黑体。站点要求「零外链、双击即可离线浏览」，所以不能引外部字体
       （OPPO 官网用的 OPPOSans-Ver2 是自研字体，无法外链引用），
       改为按「现代中文黑体」优先的系统字体栈，观感对齐 OPPO 那种干净利落的无衬线。
       刻意不把 "SimHei"（Windows 黑体）放进来：它字形老旧、笔画粗糙，
       放在现代官网里显廉价。PingFang SC / 微软雅黑 / 思源黑体才是同类里更好的选择。 */
    --font: "OPPO Sans", "HarmonyOS Sans SC", "PingFang SC",
            "Microsoft YaHei UI", "Microsoft YaHei", "Source Han Sans SC",
            "Noto Sans SC", "Hiragino Sans GB", "Segoe UI", system-ui,
            -apple-system, "Helvetica Neue", Arial, sans-serif;
    --font-num: var(--font);
}

* { margin: 0; padding: 0; box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
    font-family: var(--font);
    color: var(--text);
    background: var(--bg);
    font-size: 15px;
    line-height: 1.75;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
    text-rendering: optimizeLegibility;
    /* 刻意不加 font-synthesis-weight: none。
       微软雅黑只有 400 / 700 两档，一旦禁掉合成加粗，所有 font-weight:500/600
       都会按 CSS 字体匹配规则静默回退到 400 —— 全站 14 处本该强调的地方
       视觉层级会直接塌掉。放开后 Chrome 做轻度 stroke 加粗，层级保得住；
       在 macOS（PingFang SC 自带 500/600）上则直接命中真实字重，效果更好。 */
}
img { max-width: 100%; display: block; border: 0; }
a { color: inherit; text-decoration: none; }
ul, ol { list-style: none; }

.wrap { max-width: var(--wrap); margin: 0 auto; padding: 0 24px; }
.sr-only {
    position: absolute; width: 1px; height: 1px; padding: 0; margin: -1px;
    overflow: hidden; clip: rect(0,0,0,0); white-space: nowrap; border: 0;
}

/* ---------------- 顶部导航 ---------------- */
.topbar {
    background: var(--navy);
    color: #c7d4e3;
    font-size: 13px;
    line-height: 36px;
    /* 语言下拉是绝对定位，必须压过下面 z-index:100 的 sticky header，
       否则展开时会被 header 盖住一半 */
    position: relative; z-index: 110;
}
.topbar .wrap { display: flex; justify-content: space-between; align-items: center; }
.topbar a:hover { color: #fff; }
.topbar-right { display: flex; align-items: center; gap: 14px; }
.topbar-tel { color: #fff; font-weight: 600; letter-spacing: .5px; }
.topbar-tel::before { content: "☎ "; color: var(--red); }

/* ---------------- 语言切换器 ---------------- */
.lang-switch { position: relative; display: inline-flex; align-items: center; }
.lang-btn {
    display: inline-flex; align-items: center; gap: 6px;
    height: 24px; padding: 0 9px;
    background: rgba(255, 255, 255, .08);
    border: 1px solid rgba(255, 255, 255, .18);
    border-radius: 4px;
    color: #dce6f2; font-family: inherit; font-size: 12.5px; line-height: 1;
    cursor: pointer;
    transition: background .22s ease, border-color .22s ease, color .22s ease;
}
.lang-btn:hover, .lang-switch.open .lang-btn {
    background: rgba(255, 255, 255, .17);
    border-color: rgba(255, 255, 255, .36);
    color: #fff;
}
/* 用两笔画出地球轮廓，不用 emoji 🌐 —— emoji 在各平台字重/配色差异太大，
   放在 13px 的深色顶栏里观感不可控 */
.lang-globe {
    position: relative; width: 12px; height: 12px; flex: 0 0 auto;
    border: 1.4px solid currentColor; border-radius: 50%; opacity: .85;
}
.lang-globe::before, .lang-globe::after {
    content: ""; position: absolute; left: 50%; top: 50%; transform: translate(-50%, -50%);
}
.lang-globe::before { width: 100%; height: 1.4px; background: currentColor; }
.lang-globe::after {
    width: 5px; height: 100%;
    border-left: 1.4px solid currentColor; border-right: 1.4px solid currentColor;
}
.lang-caret {
    width: 5px; height: 5px; margin-top: -3px;
    border-right: 1.4px solid currentColor; border-bottom: 1.4px solid currentColor;
    transform: rotate(45deg); opacity: .7;
    transition: transform .28s cubic-bezier(.48, .04, .52, .96),
                margin-top .28s cubic-bezier(.48, .04, .52, .96);
}
.lang-switch:hover .lang-caret, .lang-switch.open .lang-caret {
    transform: rotate(225deg); margin-top: 3px; opacity: 1;
}
.lang-menu {
    position: absolute; top: calc(100% + 8px); right: 0; min-width: 128px;
    background: #fff; border: 1px solid var(--line); border-top: 3px solid var(--red);
    box-shadow: 0 16px 36px rgba(14, 42, 71, .18);
    padding: 6px 0;
    opacity: 0; visibility: hidden; transform: translateY(-8px);
    pointer-events: none;
    transition: opacity .22s cubic-bezier(.48, .04, .52, .96),
                transform .22s cubic-bezier(.48, .04, .52, .96),
                visibility 0s linear .22s;
}
/* :focus-within 让键盘用户也能打开；.open 由 main.js 在触屏点击时挂上 */
.lang-switch:hover .lang-menu,
.lang-switch:focus-within .lang-menu,
.lang-switch.open .lang-menu {
    opacity: 1; visibility: visible; transform: translateY(0); pointer-events: auto;
    transition-delay: 0s;
}
/* 菜单挂在按钮下方 8px，而 .lang-switch 的高度只有按钮那 24px —— 鼠标往下
   移动时必然经过这段没有任何元素的空隙，一旦离开 .lang-switch 的盒子
   :hover 立即失效，菜单在光标到达前就收起来了，等于点不到。
   用一块透明伪元素把空隙盖住，热区连续，视觉完全不变。 */
.lang-menu::before {
    content: ""; position: absolute; left: 0; right: 0; top: -8px; height: 8px;
}
.lang-menu a {
    display: block; padding: 8px 16px; font-size: 13.5px; line-height: 1.5;
    color: var(--text-2); white-space: nowrap;
    transition: background .2s ease, color .2s ease,
                padding-left .24s cubic-bezier(.4, .8, .74, 1);
}
.lang-menu a:hover { background: var(--blue-light); color: var(--navy-3); padding-left: 22px; }
.lang-menu a.active { color: var(--red); font-weight: 600; }

/* slogan + 电话 + 语言切换共需约 570px，窄于 600px 必然换行、把顶栏撑成两行。
   小屏直接收掉 slogan，只留对用户更有用的服务热线与语言入口。 */
@media (max-width: 600px) {
    .topbar-slogan { display: none; }
    .topbar .wrap { justify-content: center; }
    .topbar-right { gap: 10px; }
}
/* 英文站「Service Hotline 400-820-8795」比中文长近 50px，320px 宽下会顶到边 */
@media (max-width: 400px) {
    .topbar { font-size: 12px; }
    .topbar-right { gap: 8px; }
    .lang-btn { padding: 0 7px; }
}

.site-header {
    position: sticky; top: 0; z-index: 100;
    background: #fff;
    border-bottom: 1px solid var(--line);
    box-shadow: var(--shadow);
}
.header-inner {
    display: flex; align-items: center; justify-content: space-between;
    height: 76px; gap: 24px;
}
.logo { display: flex; align-items: center; flex-shrink: 0; }
.logo-img { display: block; height: 42px; width: auto; }
.footer-brand .logo-img { height: 40px; }

.nav { display: flex; align-items: center; flex-wrap: nowrap; }
.nav > li { position: relative; }
.nav > li > a {
    position: relative;
    display: flex; align-items: center; gap: 5px;
    height: 76px; padding: 0 var(--nav-pad);
    font-size: 14.5px; font-weight: 500; letter-spacing: .3px;
    color: var(--text);
    white-space: nowrap;
    /* 悬停背景从底部向上生长。用 background-size 而不是 background-color：
       background-size 是可过渡的，能做出「长出来」的层次感，整块变色则很生硬。 */
    background-image: linear-gradient(180deg,
        rgba(31,111,178,0) 0%, rgba(31,111,178,.10) 100%);
    background-repeat: no-repeat;
    background-position: center bottom;
    background-size: 100% 0;
    transition: color .25s cubic-bezier(.4,.8,.74,1),
                background-size .32s cubic-bezier(.4,.8,.74,1);
}
/* 下划线：从左扫入、向右扫出。
   手法参考 amwerk/munich —— 收起时 transform-origin 在右（缩回右侧），
   展开时切到左（从左侧扫出），比单纯 scaleX 有方向感得多。 */
.nav > li > a::after {
    content: "";
    position: absolute; left: var(--nav-pad); right: var(--nav-pad); bottom: 0;
    height: 3px; border-radius: 3px 3px 0 0;
    background: var(--red);
    transform: scaleX(0);
    transform-origin: right center;
    transition: transform .34s cubic-bezier(.65,.05,.36,1);
}
.nav > li > a:hover,
.nav > li > a.active {
    color: var(--navy-3);
    background-size: 100% 100%;
}
.nav > li > a:hover::after,
.nav > li > a.active::after {
    transform: scaleX(1);
    transform-origin: left center;
}
/* 下拉箭头：hover 时翻转 180°（参考 oppo 的 chevron 处理） */
.nav-chev {
    width: 7px; height: 7px; margin-top: -3px; flex: 0 0 auto;
    border-right: 1.6px solid currentColor;
    border-bottom: 1.6px solid currentColor;
    transform: rotate(45deg);
    opacity: .5;
    transition: transform .3s cubic-bezier(.48,.04,.52,.96),
                opacity .3s ease,
                margin-top .3s cubic-bezier(.48,.04,.52,.96);
}
.nav > li:hover .nav-chev {
    transform: rotate(225deg);
    margin-top: 3px;
    opacity: 1;
}

.dropdown {
    position: absolute; top: 100%; left: 0; min-width: 248px;
    background: #fff; border: 1px solid var(--line);
    border-top: 3px solid var(--red);
    box-shadow: 0 20px 44px rgba(14,42,71,.16);
    padding: 8px 0 10px;
    opacity: 0; visibility: hidden;
    transform: translateY(-10px);      /* 从上方 -10px 淡入下滑（oppo 手法） */
    pointer-events: none;
    transition: opacity .24s cubic-bezier(.48,.04,.52,.96),
                transform .24s cubic-bezier(.48,.04,.52,.96),
                visibility 0s linear .24s;
}
.nav > li:hover .dropdown {
    opacity: 1; visibility: visible; transform: translateY(0);
    pointer-events: auto;
    transition-delay: 0s;
}
.dropdown a {
    position: relative;
    display: block; padding: 10px 20px 10px 22px;
    font-size: 14px; color: var(--text-2);
    transition: color .22s ease,
                padding-left .28s cubic-bezier(.4,.8,.74,1);
}
/* 左侧红色指示条：从中心向上下展开 */
.dropdown a::before {
    content: "";
    position: absolute; left: 0; top: 50%;
    width: 3px; height: 0;
    background: var(--red);
    transform: translateY(-50%);
    transition: height .28s cubic-bezier(.4,.8,.74,1);
}
.dropdown a:hover {
    color: var(--navy-3);
    background: linear-gradient(90deg, var(--blue-light) 0%, rgba(232,241,250,0) 88%);
    padding-left: 28px;
}
.dropdown a:hover::before { height: 58%; }
.dropdown .dd-title {
    padding: 8px 20px 8px 22px; font-size: 11.5px; font-weight: 600;
    color: var(--text-3); letter-spacing: 1.4px;
}

.nav-toggle {
    display: none; width: 44px; height: 44px; border: 1px solid var(--line);
    background: #fff; border-radius: var(--radius); cursor: pointer;
    font-size: 20px; color: var(--navy);
}

/* ---------------- 首页 Hero ---------------- */
/* 官方实拍场景图铺满 + 左深右透遮罩。原方案是「深蓝渐变 + 右侧贴一张白底
   产品图」，白底图在渐变上必然出现白框，与整站色调割裂。 */
.hero {
    position: relative; overflow: hidden;
    min-height: 560px;
    display: flex; align-items: center;
    background: #08203a;            /* 图片未加载时的兜底底色 */
    color: #fff;
}
.hero-bg { position: absolute; inset: 0; z-index: 0; }
.hero-bg img {
    display: block; width: 100%; height: 100%;
    object-fit: cover;
    object-position: 58% 50%;       /* 保住画面中右侧的机器主体 */
}
.hero-mask {
    position: absolute; inset: 0; z-index: 1;
    /* 这张 1920x768（比例 2.5）放进 1440x560（比例 2.57）的容器，cover 后
       只裁掉 16px 高度，**水平方向不裁** —— 所以 object-position 的水平参数
       是无效的，机器位置无法靠它调整。唯一可控的就是把深色区加宽加深，
       让整段文案都落在足够暗的区域里。 */
    background: linear-gradient(100deg,
        rgba(4,18,36,.96) 0%,
        rgba(5,22,42,.94) 36%,
        rgba(6,28,52,.86) 52%,
        rgba(8,36,64,.46) 72%,
        rgba(10,44,78,.14) 88%,
        rgba(12,50,88,.05) 100%);
}
.hero-inner {
    position: relative; z-index: 2;
    /* 必须分开写上下 padding：用简写 padding: 92px 0 会把 .wrap 的左右
       24px 内边距清成 0（同优先级、后定义者胜），窄屏下正文直接贴边被裁。 */
    padding-top: 92px; padding-bottom: 92px;
}
/* 540px：正文正好排 2 行。收到 500px 会挤成 3 行、末行只剩「案。」一个孤字。 */
.hero-copy { max-width: 540px; }
.hero-tag {
    display: inline-block; padding: 5px 14px; margin-bottom: 20px;
    border: 1px solid rgba(255,255,255,.32); border-radius: 40px;
    font-size: 12.5px; letter-spacing: 2px; color: #cfe0f2;
}
.hero h1 {
    font-size: 46px; line-height: 1.28; font-weight: 700;
    letter-spacing: -.4px; margin-bottom: 20px;
    text-shadow: 0 2px 18px rgba(0,0,0,.4);
}
.hero h1 em { font-style: normal; color: #6db4f0; }
.hero p.lead {
    font-size: 16.5px; color: #c2d4e6; max-width: 560px; margin-bottom: 34px;
    text-shadow: 0 1px 10px rgba(0,0,0,.4);
}
.hero-actions { display: flex; gap: 14px; flex-wrap: wrap; }

/* ---------------- 内页横幅（联系页等） ---------------- */
.page-banner {
    position: relative; overflow: hidden;
    min-height: 300px;
    display: flex; align-items: center;
    background: #08203a;
    color: #fff;
}
.page-banner-bg { position: absolute; inset: 0; z-index: 0; }
.page-banner-bg img {
    display: block; width: 100%; height: 100%;
    object-fit: cover;
    object-position: 50% 42%;
}
.page-banner-mask {
    position: absolute; inset: 0; z-index: 1;
    background: linear-gradient(100deg,
        rgba(4,18,36,.94) 0%,
        rgba(5,22,42,.86) 40%,
        rgba(8,36,64,.58) 72%,
        rgba(10,44,78,.36) 100%);
}
.page-banner-inner {
    position: relative; z-index: 2;
    padding-top: 62px; padding-bottom: 62px;
}
.page-banner h1 {
    font-size: 38px; line-height: 1.25; margin: 8px 0 12px;
    text-shadow: 0 2px 16px rgba(0,0,0,.4);
}
.page-banner p { font-size: 16px; color: #c2d4e6; max-width: 560px; }
.page-banner .kicker { color: #9dc6ec; }

.btn {
    display: inline-flex; align-items: center; gap: 8px;
    padding: 13px 30px; border-radius: var(--radius);
    font-size: 15px; font-weight: 600; cursor: pointer;
    border: 1px solid transparent; transition: .2s;
}
.btn-red { background: var(--red); color: #fff; }
.btn-red:hover { background: var(--red-dark); transform: translateY(-2px); box-shadow: 0 10px 22px rgba(200,16,46,.3); }
.btn-ghost { border-color: rgba(255,255,255,.5); color: #fff; }
.btn-ghost:hover { background: rgba(255,255,255,.12); border-color: #fff; }
.btn-navy { background: var(--navy); color: #fff; }
.btn-navy:hover { background: var(--navy-3); }
.btn-line { border-color: var(--line); color: var(--text); background: #fff; }
.btn-line:hover { border-color: var(--navy-3); color: var(--navy-3); }

/* ---------------- 数据条 ---------------- */
.stats-bar { background: var(--bg-soft); border-bottom: 1px solid var(--line); }
.stats-grid {
    display: grid; grid-template-columns: repeat(4, 1fr);
    text-align: center; padding: 30px 0;
}
.stats-grid .num {
    font-size: 32px; font-weight: 700; color: var(--navy);
    letter-spacing: 1px; line-height: 1.2;
}
.stats-grid .num small { font-size: 16px; font-weight: 600; margin-left: 2px; }
/* 电话号码比 "62款" 长得多，单独降字号避免挤爆栅格 */
.stats-grid .num.tel { font-size: 25px; letter-spacing: .5px; white-space: nowrap; }
.stats-grid .lbl { font-size: 13.5px; color: var(--text-2); margin-top: 4px; }
.stats-grid > div + div { border-left: 1px solid var(--line); }

/* ---------------- 通用区块 ---------------- */
.section { padding: 68px 0; }
.section.soft { background: var(--bg-soft); }
.sec-head { text-align: center; margin-bottom: 44px; }
.sec-head .kicker {
    display: block; font-size: 13px; letter-spacing: 3px;
    color: var(--red); font-weight: 700; margin-bottom: 10px;
}
.sec-head h1, .sec-head h2 {
    font-size: 32px; font-weight: 700; color: var(--navy);
    /* 中文标题用负字距才紧凑现代；正字距是英文排版的习惯，套到中文上会显松散老派 */
    letter-spacing: -.2px; line-height: 1.3;
}
.sec-head p { color: var(--text-2); margin-top: 12px; font-size: 15px; }
.sec-head::after {
    content: ""; display: block; width: 52px; height: 3px;
    background: var(--red); margin: 20px auto 0;
}
.sec-head.left { text-align: left; }
.sec-head.left::after { margin-left: 0; }

/* ---------------- 分类导航卡 ---------------- */
.cat-grid {
    display: grid; grid-template-columns: repeat(auto-fill, minmax(272px, 1fr));
    gap: 20px;
}
.cat-card {
    position: relative; display: flex; flex-direction: column;
    height: 100%; overflow: hidden;
    background: #fff; border: 1px solid var(--line);
    border-radius: var(--radius); padding: 28px 26px 24px;
    transition: .22s;
}
.cat-card::before {
    content: ""; position: absolute; left: 0; top: 0; bottom: 0;
    width: 4px; background: var(--red); transform: scaleY(0);
    transform-origin: top; transition: .25s;
}
.cat-card:hover {
    box-shadow: var(--shadow-lg); border-color: #cfdae8;
    transform: translateY(-3px);
}
.cat-card:hover::before { transform: scaleY(1); }
.cat-card .ic {
    width: 46px; height: 46px; border-radius: 8px;
    background: var(--blue-light); color: var(--navy-3);
    display: flex; align-items: center; justify-content: center;
    font-size: 21px; margin-bottom: 16px;
}
.cat-card h3 { font-size: 17px; font-weight: 700; color: var(--navy); margin-bottom: 8px; }
.cat-card p { font-size: 13.5px; color: var(--text-2); line-height: 1.7; min-height: 44px; }
.cat-card .more {
    display: inline-block; margin-top: auto; padding-top: 14px;
    font-size: 13px; color: var(--blue); font-weight: 600;
}
.cat-card:hover .more { color: var(--red); }

/* ---------------- 产品卡 ---------------- */
.prod-grid {
    display: grid; grid-template-columns: repeat(auto-fill, minmax(258px, 1fr));
    gap: 22px;
}
.prod-card {
    display: flex; flex-direction: column; overflow: hidden;
    background: #fff; border: 1px solid var(--line);
    border-radius: var(--radius); transition: .22s;
}
.prod-card:hover {
    box-shadow: var(--shadow-lg); border-color: #cfdae8;
    transform: translateY(-4px);
}
.prod-thumb {
    position: relative; height: 208px; background: var(--bg-soft);
    display: flex; align-items: center; justify-content: center; overflow: hidden;
}
.prod-thumb img {
    width: 100%; height: 100%; object-fit: contain;
    padding: 16px; transition: transform .35s;
}
.prod-card:hover .prod-thumb img { transform: scale(1.06); }
.prod-thumb .noimg {
    color: var(--text-3); font-size: 13px; letter-spacing: 1px;
}
.prod-thumb .badge {
    position: absolute; left: 12px; top: 12px;
    background: var(--red); color: #fff;
    font-size: 11.5px; font-weight: 600; letter-spacing: .5px;
    padding: 3px 9px; border-radius: 3px;
}
.prod-body { padding: 18px 20px 20px; display: flex; flex-direction: column; flex: 1; }
.prod-body h3 {
    font-size: 16px; font-weight: 700; color: var(--navy);
    line-height: 1.45; margin-bottom: 6px;
}
.prod-body h3 a:hover { color: var(--blue); }
.prod-model {
    font-size: 12.5px; color: var(--text-3); font-variant-numeric: tabular-nums;
    margin-bottom: 10px; letter-spacing: .5px;
}
.prod-sum {
    font-size: 13.5px; color: var(--text-2); line-height: 1.7;
    display: -webkit-box; -webkit-line-clamp: 2; -webkit-box-orient: vertical;
    overflow: hidden; margin-bottom: 14px; flex: 1;
}
.prod-specs {
    display: flex; flex-wrap: wrap; gap: 6px 14px;
    padding-top: 12px; border-top: 1px dashed var(--line);
    font-size: 12.5px; color: var(--text-2);
}
.prod-specs span b { color: var(--navy); font-weight: 600; }

/* ---------------- 面包屑 ---------------- */
/* 程序化滚动/锚点跳转时给吸顶导航留出空间，避免目标元素被 header 盖住点不到 */
[id], a { scroll-margin-top: 92px; }

.crumb-bar {
    background: var(--bg-soft); border-bottom: 1px solid var(--line);
    font-size: 13.5px; color: var(--text-2); padding: 15px 0;
}
.crumb-bar a:hover { color: var(--blue); }
.crumb-bar .sep { margin: 0 9px; color: var(--text-3); }
.crumb-bar .cur { color: var(--navy); font-weight: 600; }

/* ---------------- 产品详情 ---------------- */
.pd-hero { padding: 44px 0 52px; border-bottom: 1px solid var(--line); }
.pd-top {
    display: grid; grid-template-columns: minmax(0, 1.02fr) minmax(0, .98fr);
    gap: 52px; align-items: start;
}
.pd-gallery { position: sticky; top: 100px; }
.pd-main {
    position: relative; background: var(--bg-soft);
    border: 1px solid var(--line); border-radius: var(--radius);
    height: 430px; display: flex; align-items: center; justify-content: center;
    overflow: hidden; margin-bottom: 14px;
}
.pd-main img {
    max-width: 100%; max-height: 100%; object-fit: contain; padding: 22px;
    cursor: zoom-in;
}
.pd-thumbs { display: flex; flex-wrap: wrap; gap: 10px; }
.pd-thumbs button {
    flex: 0 0 84px; height: 84px; padding: 5px;
    background: #fff; border: 1px solid var(--line); border-radius: 5px;
    cursor: pointer; transition: .18s; overflow: hidden;
}
.pd-thumbs button img { width: 100%; height: 100%; object-fit: contain; }
.pd-thumbs button:hover { border-color: var(--blue); }
.pd-thumbs button.active { border-color: var(--red); box-shadow: 0 0 0 2px rgba(200,16,46,.15); }

.pd-info h1 {
    font-size: 30px; font-weight: 700; color: var(--navy);
    line-height: 1.35; margin-bottom: 12px;
}
.pd-meta { display: flex; flex-wrap: wrap; gap: 10px; margin-bottom: 20px; }
.pd-meta .tag {
    font-size: 12.5px; padding: 4px 12px; border-radius: 3px;
    background: var(--blue-light); color: var(--navy-3); font-weight: 600;
}
.pd-meta .tag.red { background: #fdeaee; color: var(--red); }
.pd-meta .tag.gray { background: var(--bg-soft2); color: var(--text-2); }
.pd-summary {
    font-size: 15px; color: var(--text-2); line-height: 1.9;
    padding: 18px 20px; background: var(--bg-soft);
    border-left: 3px solid var(--red); border-radius: 0 var(--radius) var(--radius) 0;
    margin-bottom: 22px;
}
.pd-quick {
    display: grid; grid-template-columns: repeat(2, 1fr);
    gap: 1px; background: var(--line); border: 1px solid var(--line);
    border-radius: var(--radius); overflow: hidden; margin-bottom: 24px;
}
.pd-quick .qi { background: #fff; padding: 13px 16px; }
.pd-quick .qi dt { font-size: 12px; color: var(--text-3); margin-bottom: 3px; }
.pd-quick .qi dd { font-size: 14.5px; font-weight: 600; color: var(--navy); }
.pd-features { display: flex; flex-wrap: wrap; gap: 8px; margin-bottom: 24px; }
.pd-features span {
    font-size: 13px; padding: 6px 14px; border-radius: 40px;
    background: var(--bg-soft2); color: var(--text-2);
}
.pd-features span::before { content: "✓ "; color: var(--red); font-weight: 700; }
.pd-actions { display: flex; gap: 12px; flex-wrap: wrap; }

/* 文章 */
.article-sec { padding: 52px 0; border-bottom: 1px solid var(--line); }
.article-sec .inner { max-width: 900px; margin: 0 auto; }
.article-sec h2 {
    font-size: 25px; font-weight: 700; color: var(--navy);
    line-height: 1.45; margin-bottom: 26px; padding-bottom: 18px;
    border-bottom: 2px solid var(--line);
}
.md h3 {
    font-size: 18px; font-weight: 700; color: var(--navy);
    margin: 30px 0 12px; padding-left: 12px;
    border-left: 3px solid var(--red); line-height: 1.5;
}
.md p { margin-bottom: 15px; color: var(--text-2); font-size: 15.5px; line-height: 2; }
.md strong { color: var(--navy); font-weight: 700; }
.md ul, .md ol { margin: 0 0 17px; padding-left: 24px; }
.md ul li { list-style: disc; margin-bottom: 8px; color: var(--text-2); }
.md ol li { list-style: decimal; margin-bottom: 8px; color: var(--text-2); }
.md ul li::marker { color: var(--red); }
.md ol li::marker { color: var(--red); font-weight: 700; }
.md-table-scroll {
    overflow-x: auto; margin: 6px 0 22px;
    border: 1px solid var(--line); border-radius: var(--radius);
}
.md-table { width: 100%; min-width: 440px; border-collapse: collapse; font-size: 14px; }
.md-table tr { border-bottom: 1px solid var(--line); }
.md-table tr:last-child { border-bottom: none; }
.md-table th {
    background: var(--navy); color: #fff; font-weight: 600;
    text-align: left; padding: 12px 16px; white-space: nowrap;
}
.md-table td { padding: 11px 16px; color: var(--text-2); }
.md-table tr:nth-child(even) td { background: var(--bg-soft); }

/* 参数 */
.spec-sec { padding: 52px 0; border-bottom: 1px solid var(--line); }
.spec-block { margin-bottom: 34px; }
.spec-block h2, .spec-block h3 {
    font-size: 17px; font-weight: 700; color: var(--navy);
    margin-bottom: 14px; padding-left: 12px;
    border-left: 3px solid var(--navy-3);
}
.kv-table { width: 100%; border-collapse: collapse; font-size: 14.5px; border: 1px solid var(--line); }
.kv-table tr { border-bottom: 1px solid var(--line); }
.kv-table tr:last-child { border-bottom: none; }
.kv-table th {
    width: 220px; text-align: left; font-weight: 500; color: var(--text-2);
    background: var(--bg-soft); padding: 12px 18px; border-right: 1px solid var(--line);
}
.kv-table td { padding: 12px 18px; color: var(--text); }
.grid-table { width: 100%; border-collapse: collapse; font-size: 13.5px; }
.grid-table tr { border-bottom: 1px solid var(--line); }
.grid-table th, .grid-table td {
    padding: 9px 12px; border-right: 1px solid var(--line);
    text-align: left; white-space: nowrap;
}
.grid-table th:last-child, .grid-table td:last-child { border-right: none; }
.grid-table th { background: var(--navy-2); color: #fff; font-weight: 600; }
.grid-table tbody tr:nth-child(even) td { background: var(--bg-soft); }
.spec-src { font-size: 12.5px; color: var(--text-3); margin-top: 8px; }

/* 图集 */
.gallery-grid {
    display: grid; grid-template-columns: repeat(auto-fill, minmax(216px, 1fr)); gap: 16px;
}
.gallery-item {
    background: #fff; border: 1px solid var(--line); border-radius: var(--radius);
    overflow: hidden; cursor: zoom-in; transition: .2s;
}
.gallery-item:hover { box-shadow: var(--shadow-lg); transform: translateY(-3px); }
.gallery-item img { width: 100%; height: 178px; object-fit: contain; padding: 12px; background: var(--bg-soft); }
.gallery-item figcaption {
    padding: 10px 13px; font-size: 12.5px; color: var(--text-2);
    border-top: 1px solid var(--line); line-height: 1.55;
}

/* 相关产品 */
.related-grid {
    display: grid; grid-template-columns: repeat(auto-fill, minmax(216px, 1fr)); gap: 18px;
}
.related-item {
    display: flex; gap: 14px; align-items: center; padding: 14px;
    background: #fff; border: 1px solid var(--line); border-radius: var(--radius);
    transition: .2s;
}
.related-item:hover { border-color: var(--blue); box-shadow: var(--shadow); }
.related-item img { width: 66px; height: 66px; object-fit: contain; flex-shrink: 0; background: var(--bg-soft); border-radius: 4px; padding: 4px; }
.related-item strong { display: block; font-size: 14px; color: var(--navy); line-height: 1.45; }
.related-item span { font-size: 12px; color: var(--text-3); font-variant-numeric: tabular-nums; }

/* ---------------- 优势 / 图文 ---------------- */
.adv-grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(240px, 1fr)); gap: 26px; }
.adv-item { text-align: center; padding: 30px 22px; background: #fff; border: 1px solid var(--line); border-radius: var(--radius); transition: .2s; }
.adv-item:hover { box-shadow: var(--shadow-lg); transform: translateY(-3px); }
.adv-item .ic {
    width: 58px; height: 58px; margin: 0 auto 16px; border-radius: 50%;
    background: var(--blue-light); color: var(--navy-3);
    display: flex; align-items: center; justify-content: center; font-size: 25px;
}
.adv-item h3 { font-size: 16.5px; font-weight: 700; color: var(--navy); margin-bottom: 9px; }
.adv-item p { font-size: 13.5px; color: var(--text-2); line-height: 1.8; }

/* ---------------- CTA ---------------- */
.cta {
    background: linear-gradient(115deg, #08203a 0%, var(--navy) 55%, #1a4877 100%);
    color: #fff; padding: 56px 0; text-align: center;
}
.cta h2 { font-size: 28px; font-weight: 700; margin-bottom: 12px; letter-spacing: .5px; }
.cta p { color: #b9cde2; margin-bottom: 28px; font-size: 15.5px; }
.cta .tel { font-size: 34px; font-weight: 700; color: #6db4f0; letter-spacing: 2px; margin-bottom: 24px; }
.cta .btns { display: flex; gap: 14px; justify-content: center; flex-wrap: wrap; }

/* ---------------- 页脚 ---------------- */
.site-footer { background: #081c30; color: #93a7bd; padding: 52px 0 0; font-size: 13.5px; }
.footer-grid {
    display: grid; grid-template-columns: 1.5fr 1fr 1fr 1.2fr;
    gap: 40px; padding-bottom: 40px;
}
.footer-grid h4 {
    color: #fff; font-size: 15px; font-weight: 700;
    margin-bottom: 16px; padding-bottom: 10px; border-bottom: 1px solid #17334f;
}
.footer-grid li { margin-bottom: 9px; line-height: 1.7; }
.footer-grid a:hover { color: #fff; }
.footer-brand { display: flex; align-items: center; gap: 11px; margin-bottom: 14px; }
.footer-brand b { color: #fff; font-size: 19px; letter-spacing: 2px; }
.footer-bottom {
    border-top: 1px solid #17334f; padding: 18px 0;
    display: flex; justify-content: space-between; gap: 16px; flex-wrap: wrap;
    font-size: 12.5px; color: #6c8299;
}

/* ---------------- 灯箱 ---------------- */
.lightbox {
    position: fixed; inset: 0; z-index: 900; display: none;
    background: rgba(6,18,32,.93); align-items: center; justify-content: center;
    padding: 40px;
}
.lightbox.show { display: flex; }
.lightbox img { max-width: 92%; max-height: 86%; object-fit: contain; background: #fff; border-radius: 4px; }
.lightbox .cap { position: absolute; bottom: 26px; left: 0; right: 0; text-align: center; color: #c7d4e3; font-size: 14px; }
.lightbox .close {
    position: absolute; top: 22px; right: 28px; width: 44px; height: 44px;
    background: rgba(255,255,255,.12); border: 0; border-radius: 50%;
    color: #fff; font-size: 22px; cursor: pointer;
}
.lightbox .close:hover { background: rgba(255,255,255,.24); }

/* ---------------- 空态 / 404 ---------------- */
.empty { text-align: center; padding: 70px 20px; color: var(--text-3); }
.empty .big { font-size: 58px; margin-bottom: 14px; opacity: .5; }
.nf { text-align: center; padding: 110px 20px; }
.nf h1 { font-size: 96px; color: var(--navy); line-height: 1; margin-bottom: 18px; letter-spacing: 4px; }
.nf p { color: var(--text-2); margin-bottom: 30px; font-size: 16px; }

/* ---------------- 响应式 ---------------- */
/* 英文导航标签天然比中文长得多（"Screw Compressors" 17 字符 vs
   "螺杆式空压机（微油）" 10 字），6 个一级项拼起来 1152px。1440px 放得下，
   1366px 就顶出 31px —— 而 1320px 以下才有收紧规则，1366 正好落进空档。
   这一段单独把英文收进来，中文站不受影响。 */
@media (min-width: 1321px) and (max-width: 1439px) {
    html[lang="en"] { --nav-pad: 8px; }
    html[lang="en"] .nav > li > a { font-size: 13px; }
    html[lang="en"] .header-inner { gap: 12px; }
}
@media (max-width: 1320px) {
    /* 导航项多，窄屏逐级收紧，避免换行/溢出把下方内容盖住 */
    :root { --nav-pad: 8px; }
    .nav > li > a { font-size: 13px; }
    .header-inner { gap: 12px; }
    .logo-img { height: 38px; }
}
@media (max-width: 1150px) {
    :root { --nav-pad: 6px; }
    .nav > li > a { font-size: 12.5px; }
    .logo-img { height: 34px; }
}
/* 导航项较多，1024px 以下直接收进汉堡菜单，避免挤压换行/横向溢出 */
@media (max-width: 1024px) {
    .nav { display: none; }
    .nav.open {
        display: flex; flex-direction: column; align-items: stretch;
        position: absolute; top: 100%; left: 0; right: 0;
        background: #fff; border-top: 1px solid var(--line);
        box-shadow: var(--shadow-lg); padding: 8px 0; gap: 0;
        max-height: 72vh; overflow-y: auto;
    }
    /* 触屏没有 hover，滑动下划线没意义：改用左侧竖条标记当前/悬停项 */
    .nav.open > li > a {
        height: auto; line-height: 1.5; padding: 14px 24px;
        border-left: 3px solid transparent;
        font-size: 14.5px;
    }
    .nav.open > li > a::after { display: none; }
    .nav.open > li > a:hover,
    .nav.open > li > a.active {
        background: var(--blue-light);
        border-left-color: var(--red);
    }
    .nav.open .nav-chev { margin-left: auto; }
    .nav.open .dropdown {
        position: static; opacity: 1; visibility: visible; transform: none;
        box-shadow: none; border: 0; border-top: 0; padding: 0 0 6px 12px;
        pointer-events: auto;
    }
    .nav.open .dropdown a::before { display: none; }
    .nav.open .dropdown a:hover { background: none; padding-left: 22px; }
    /* 下拉里的分类名标题在桌面端是「面板归属提示」，移动端父项名就在上一行，
       再显示一遍纯属重复 */
    .nav.open .dropdown .dd-title { display: none; }
    .nav-toggle { display: block; }
}
@media (max-width: 1080px) {
    .hero { min-height: 500px; }
    .hero-inner { padding-top: 76px; padding-bottom: 76px; }
    .hero h1 { font-size: 34px; }
    .hero-mask {
        background: linear-gradient(100deg,
            rgba(5,21,40,.95) 0%, rgba(6,26,48,.88) 42%,
            rgba(8,32,58,.62) 72%, rgba(10,42,74,.34) 100%);
    }
    .pd-top { grid-template-columns: 1fr; gap: 34px; }
    .pd-gallery { position: static; }
    .footer-grid { grid-template-columns: 1fr 1fr; gap: 30px; }
}
@media (max-width: 860px) {
    .stats-grid { grid-template-columns: repeat(2, 1fr); gap: 20px 0; }
    .stats-grid > div:nth-child(3) { border-left: 0; }
    .sec-head h1, .sec-head h2 { font-size: 24px; }
    .hero { min-height: 440px; }
    .hero-inner { padding-top: 62px; padding-bottom: 62px; }
    .page-banner { min-height: 240px; }
    .page-banner-inner { padding-top: 46px; padding-bottom: 46px; }
    .page-banner h1 { font-size: 28px; }
    .hero h1 { font-size: 27px; }
    .hero-copy { max-width: 100%; }
    /* 16.5px 在 350px 宽下会排出 4 行、末行只剩「案。」一个孤字 */
    .hero p.lead { font-size: 15px; }
    /* 窄屏时遮罩不再分左右，整体加深保证文字可读 */
    .hero-mask { background: rgba(5,21,40,.84); }
    .hero-bg img { object-position: 66% 50%; }
    .pd-info h1 { font-size: 23px; }
    .pd-main { height: 300px; }
    .section { padding: 46px 0; }
    .footer-grid { grid-template-columns: 1fr; gap: 26px; }
    .cta .tel { font-size: 25px; }
}
@media (max-width: 520px) {
    .pd-quick { grid-template-columns: 1fr; }
    .prod-grid, .cat-grid { grid-template-columns: 1fr; }
}