/* ============================================================
   瀚钦（丹东）智能科技 · 官网共用样式（U7SI.COM）
   包含：设计 token、reset、通用工具类、导航、页脚、响应式
   各页面专属样式请写在页面内 <style> 块中
   ============================================================ */

/* ===== Token 体系 ===== */
:root{
  --ink:#081720;
  --ink-2:#0d2330;
  --ink-3:#12303d;
  --panel:#143240;
  --line:rgba(140,196,214,.16);
  --line-strong:rgba(140,196,214,.32);
  --text:#eaf4f7;
  --text-dim:#9fc0cb;
  --text-soft:#6f8f9b;
  --accent:#2ec4b6;
  --accent-2:#5ad7c9;
  --gold:#c9a24b;
  --bg-light:#eef4f6;
  --bg-light-2:#ffffff;
  --text-ink:#122b36;
  --text-ink-dim:#4a6670;
  --serif:"Noto Serif SC","Source Han Serif SC","Songti SC","SimSun",serif;
  --sans:"Noto Sans SC","PingFang SC","Microsoft YaHei",sans-serif;
  --radius:18px;
  --maxw:1180px;
}

/* ===== Reset & 基础排版 ===== */
*{margin:0;padding:0;box-sizing:border-box}
html{scroll-behavior:smooth}
body{font-family:var(--sans);color:var(--text);background:var(--ink);line-height:1.7;-webkit-font-smoothing:antialiased}
a{color:inherit;text-decoration:none}
img{max-width:100%;height:auto;display:block}
.container{max-width:var(--maxw);margin:0 auto;padding:0 28px}
section{position:relative}

/* ===== 通用标题 ===== */
.eyebrow{font-size:13px;letter-spacing:.24em;text-transform:uppercase;color:var(--accent-2);font-weight:500}
h2.title{font-family:var(--serif);font-weight:900;font-size:38px;line-height:1.25;margin:14px 0 16px;letter-spacing:.5px}
h2.title em{font-style:normal;color:var(--gold)}
.sub{color:var(--text-dim);max-width:640px;font-size:16px;font-weight:300}
.section{padding:92px 0}
.section-head{display:flex;justify-content:space-between;align-items:flex-end;gap:30px;margin-bottom:44px;flex-wrap:wrap}
.section-head .sub{margin-top:6px}

/* ===== 按钮 ===== */
.btn{display:inline-flex;align-items:center;gap:8px;border-radius:999px;padding:11px 22px;font-size:14px;font-weight:500;transition:all .2s;border:1px solid transparent;cursor:pointer;white-space:nowrap;font-family:var(--sans)}
.btn-accent{background:var(--accent);color:#04222b}
.btn-accent:hover{background:var(--accent-2)}
.btn-ghost{border-color:var(--line-strong);color:var(--text)}
.btn-ghost:hover{border-color:var(--accent);color:var(--accent-2)}
.btn-light{background:#fff;color:var(--text-ink)}
.btn-block{width:100%;justify-content:center;padding:14px}

/* ===== 顶部导航 ===== */
.nav{position:fixed;top:0;left:0;right:0;z-index:100;background:rgba(8,23,32,.82);backdrop-filter:blur(14px);border-bottom:1px solid var(--line)}
.nav .container{display:flex;align-items:center;height:68px}
.brand{display:flex;align-items:center;gap:11px;font-family:var(--serif);font-weight:900;font-size:20px;letter-spacing:1px;flex:1 1 auto;min-width:0;overflow:hidden}
.brand .mark{width:34px;height:34px;display:grid;place-items:center;flex:0 0 auto}
.brand .mark img{width:34px;height:34px;display:block}
.brand .name{display:flex;flex-direction:column;line-height:1.1;min-width:0;white-space:nowrap}
.brand .name small{font-size:11px;color:var(--text-soft);font-weight:400;letter-spacing:.06em;margin-top:2px;font-family:var(--sans);overflow:hidden;text-overflow:ellipsis}
.nav-links{display:flex;gap:30px;margin-left:auto;align-items:center}
.nav-links a{font-size:14px;color:var(--text-dim);transition:color .2s}
.nav-links a:hover{color:var(--text)}
.nav-links a.active{color:var(--accent-2)}
.nav .btn{margin-left:18px}

/* 汉堡按钮：仅 ≤1080px 出现，桌面端隐藏 */
.nav-toggle{display:none;position:relative;flex:0 0 auto;width:44px;height:44px;margin-left:12px;padding:0;border:1px solid var(--line-strong);border-radius:12px;background:transparent;cursor:pointer;transition:border-color .2s,background .2s}
.nav-toggle:hover,.nav-toggle:focus-visible{border-color:var(--accent);background:rgba(46,196,182,.1);outline:none}
.nav-toggle span{position:absolute;left:50%;width:18px;height:2px;border-radius:2px;background:var(--text);transform:translateX(-50%);transition:top .26s ease,transform .26s ease,opacity .18s ease}
.nav-toggle span:nth-child(1){top:15px}
.nav-toggle span:nth-child(2){top:21px}
.nav-toggle span:nth-child(3){top:27px}
.nav-toggle[aria-expanded="true"] span:nth-child(1){top:21px;transform:translateX(-50%) rotate(45deg)}
.nav-toggle[aria-expanded="true"] span:nth-child(2){opacity:0;transform:translateX(-50%) scaleX(.3)}
.nav-toggle[aria-expanded="true"] span:nth-child(3){top:21px;transform:translateX(-50%) rotate(-45deg)}

/* 抽屉内的 CTA 按钮：桌面端隐藏，≤1080px 显示 */
.nav-cta{display:none}

/* 抽屉展开时锁定背景滚动 */
body.nav-open{overflow:hidden}

/* ===== 页脚 ===== */
footer{border-top:1px solid var(--line);background:var(--ink);padding:40px 0}
footer .container{display:flex;justify-content:space-between;align-items:center;flex-wrap:wrap;gap:18px}
.foot-brand{display:flex;align-items:center;gap:10px;font-family:var(--serif);font-weight:900}
.foot-brand .mark{width:28px;height:28px;display:grid;place-items:center;flex:0 0 auto}
.foot-brand .mark img{width:28px;height:28px;display:block}
.foot-info{font-size:13px;color:var(--text-soft);display:flex;gap:22px;flex-wrap:wrap}
.foot-info a{color:var(--text-soft);transition:color .2s}
.foot-info a:hover{color:var(--accent-2)}
.foot-copy{width:100%;text-align:center;color:var(--text-soft);font-size:12px;border-top:1px solid var(--line);padding-top:22px;margin-top:6px}
.foot-copy a{color:inherit;text-decoration:none;transition:color .2s}
.foot-copy a:hover{color:var(--accent);text-decoration:underline}

/* ===== Toast ===== */
.toast{position:fixed;left:50%;bottom:40px;transform:translateX(-50%) translateY(80px);background:var(--accent);color:#04222b;font-weight:500;padding:14px 26px;border-radius:999px;opacity:0;transition:all .35s;z-index:200;box-shadow:0 12px 30px rgba(0,0,0,.3)}
.toast.show{opacity:1;transform:translateX(-50%) translateY(0)}

/* ===== 悬浮咨询按钮 ===== */
.float-consult-btn{position:fixed;bottom:24px;right:24px;width:60px;height:60px;border-radius:50%;background:#0F4C81;color:#fff;border:none;box-shadow:0 4px 14px rgba(15,76,129,.4);font-size:26px;z-index:9998;cursor:pointer;transition:transform .25s}
.float-consult-btn:hover{transform:scale(1.08)}
.consult-popup{position:fixed;bottom:95px;right:24px;width:380px;max-width:calc(100vw - 48px);background:#fff;border-radius:12px;box-shadow:0 6px 24px rgba(0,0,0,.28);z-index:9999;display:none;overflow:hidden}
.popup-header{background:#0F4C81;color:#fff;padding:14px 18px;display:flex;justify-content:space-between;align-items:center}
.popup-header h4{font-size:16px;margin:0;color:#fff}
.popup-header .tag{font-size:11px;background:rgba(255,255,255,.18);padding:2px 8px;border-radius:4px;letter-spacing:.04em;margin-left:8px}
.popup-close{background:transparent;border:none;color:#fff;font-size:20px;cursor:pointer}
.popup-body{padding:18px;color:#333}
.welcome-tip{background:#E6F2FB;padding:12px 14px;border-radius:6px;margin-bottom:16px;font-size:13px;color:#0F4C81;line-height:1.65}
.quick-btn-group{display:grid;grid-template-columns:1fr 1fr;gap:10px;margin-bottom:14px}
.quick-mail-btn,.quick-site-btn{padding:10px 8px;border-radius:6px;border:none;font-size:13px;cursor:pointer;text-decoration:none;text-align:center;color:#fff;display:inline-flex;align-items:center;justify-content:center;gap:4px}
.quick-mail-btn{background:#0F4C81}
.quick-site-btn{background:#2ec4b6;color:#04222b;font-weight:500}
.popup-body .form-item{margin-bottom:14px}
.popup-body label{display:block;font-size:14px;color:#333;margin-bottom:4px}
.popup-body input,.popup-body textarea{width:100%;border:1px solid #cbd5e1;border-radius:6px;padding:10px 12px;font-size:14px;font-family:var(--sans);box-sizing:border-box;color:#333;background:#fff}
.popup-body textarea{min-height:90px;resize:none}
.popup-submit{width:100%;background:#0F4C81;color:#fff;border:none;border-radius:6px;padding:11px;font-weight:bold;cursor:pointer;font-size:14px}
.tip-success{color:#009944;text-align:center;margin-top:10px;display:none;font-size:13px;line-height:1.7}
.tip-mini{font-size:12px;color:#64748B;text-align:center;margin-top:6px}

/* ===== 通用响应式 ===== */

/* 导航：≤1080px 收起为汉堡抽屉
   （顺带消除 761–1100px 区间导航项与品牌名的挤压重叠） */
@media(max-width:1080px){
  /* 顶栏 CTA 让位给汉堡按钮，改由抽屉承载，避免窄屏放不下 */
  .nav .btn{display:none}
  .nav-toggle{display:block}
  .nav-links{
    position:fixed;top:68px;left:0;right:0;z-index:99;
    flex-direction:column;align-items:stretch;gap:0;margin-left:0;
    padding:8px 28px 24px;
    background:#0b1b26;
    border-bottom:1px solid var(--line);
    max-height:calc(100vh - 68px);max-height:calc(100dvh - 68px);
    overflow-y:auto;
    opacity:0;visibility:hidden;pointer-events:none;transform:translateY(-10px);
    transition:opacity .24s ease,transform .26s ease,visibility .26s
  }
  .nav-links.open{opacity:1;visibility:visible;pointer-events:auto;transform:translateY(0)}
  .nav-links a{font-size:16px;padding:15px 2px;border-bottom:1px solid var(--line);color:var(--text-dim)}
  .nav-links a:last-of-type{border-bottom:none}
  .nav-links .nav-cta{display:block;margin-top:14px;padding:14px 2px;border-bottom:none;border-radius:999px;background:var(--accent);color:#04222b;text-align:center;font-weight:500}
  .nav-links .nav-cta:hover{background:var(--accent-2);color:#04222b}
}
@media(prefers-reduced-motion:reduce){
  .nav-links,.nav-toggle span{transition:none}
}

@media(max-width:1024px){
  .hero h1{font-size:42px}
}
@media(max-width:760px){
  .section{padding:64px 0}
  h2.title{font-size:30px}
}
@media(max-width:560px){
  .brand{font-size:16px;letter-spacing:0}
  .brand .name small{display:none}
}
@media(max-width:480px){
  .consult-popup{right:12px;bottom:85px;width:calc(100vw - 24px)}
  .float-consult-btn{bottom:14px;right:14px}
  .quick-btn-group{grid-template-columns:1fr}
}

/* ===== Dify 智能客服：聊天窗固定在视口右下，不随页面滚动 ===== */
#dify-chatbot-bubble-window{position:fixed !important;top:auto !important;left:auto !important;right:1rem !important;bottom:5.5rem !important}