/* ============ tokens ============ */
:root{
  --paper:#FFFFFF;
  --paper-2:#F7F7F5;
  --ink:#101010;
  --gray:#61615B;
  --line:#E4E4DF;
  --ikb:#0032FA;
  --ikb-deep:#0026C2;
  --sans:"PingFang SC","Hiragino Sans GB","Source Han Sans SC","Noto Sans CJK SC","Microsoft YaHei",-apple-system,BlinkMacSystemFont,"Helvetica Neue",Arial,sans-serif;
  --mono:ui-monospace,"SF Mono","JetBrains Mono","Menlo","Consolas",monospace;
  --wrap-max:1180px;
  --pad-x:clamp(20px,5vw,64px);
  --sec-y:clamp(72px,10vw,128px);
}
/* ============ reset ============ */
*,*::before,*::after{box-sizing:border-box;margin:0;padding:0}
html{scroll-behavior:smooth;-webkit-text-size-adjust:100%}
body{
  font-family:var(--sans);
  color:var(--ink);
  background:var(--paper);
  font-size:16px;
  line-height:1.8;
  font-weight:400;
  -webkit-font-smoothing:antialiased;
}
main{padding-top:64px;min-height:calc(100vh - 113px)}
img{max-width:100%;display:block}
a{color:inherit;text-decoration:none}
ul{list-style:none}
[hidden]{display:none!important}
:focus-visible{outline:2px solid var(--ikb);outline-offset:3px}
.on-ikb :focus-visible{outline-color:#fff}
::selection{background:var(--ikb);color:#fff}

.wrap{max-width:var(--wrap-max);margin:0 auto;padding-left:var(--pad-x);padding-right:var(--pad-x)}

/* ============ reveal motion ============ */
@keyframes fadeUp{from{opacity:0;transform:translateY(18px)}to{opacity:1;transform:none}}
.reveal{animation:fadeUp .6s ease both}
.reveal.in{animation:none;opacity:1;transform:none}
@media (prefers-reduced-motion:reduce){
  html{scroll-behavior:auto}
  .reveal{opacity:1;transform:none;animation:none}
  *{transition-duration:0s!important;animation:none!important}
}

/* ============ nav ============ */
.nav{
  position:fixed;top:0;left:0;right:0;z-index:100;
  background:rgba(255,255,255,.94);
  -webkit-backdrop-filter:blur(8px);backdrop-filter:blur(8px);
  border-bottom:1px solid var(--line);
}
.nav-inner{
  max-width:var(--wrap-max);margin:0 auto;
  padding:0 var(--pad-x);
  height:64px;
  display:flex;align-items:center;justify-content:space-between;gap:24px;
}
.brand{display:flex;align-items:baseline;gap:10px;font-weight:600;font-size:18px;letter-spacing:.02em}
.brand .dot{display:inline-block;width:10px;height:10px;background:var(--ikb);transform:translateY(-1px)}
.brand small{font-family:var(--mono);font-weight:400;font-size:11px;color:var(--gray);letter-spacing:.05em}
.nav-links{display:flex;gap:clamp(14px,2.4vw,30px);font-size:14px}
.nav-links a{padding:6px 2px;border-bottom:2px solid transparent;transition:border-color .2s,color .2s;white-space:nowrap}
.nav-links a:hover,
.nav-links a.active{border-bottom-color:var(--ikb);color:var(--ikb)}
.nav-toggle{
  display:none;background:none;border:1px solid var(--ink);
  font-family:var(--mono);font-size:12px;letter-spacing:.12em;
  padding:7px 14px;cursor:pointer;color:var(--ink);
}
@media (max-width:840px){
  .nav-toggle{display:block}
  .nav-links{
    display:none;
    position:absolute;top:64px;left:0;right:0;
    flex-direction:column;gap:0;
    background:var(--paper);border-bottom:1px solid var(--line);
    padding:8px 0;
  }
  .nav.open .nav-links{display:flex}
  .nav-links a{padding:13px var(--pad-x);border-bottom:1px solid var(--line);font-size:15px}
  .nav-links a:last-child{border-bottom:none}
  .nav-links a.active{border-bottom-color:var(--ikb)}
}

/* ============ hero ============ */
.hero{background:var(--paper)}
.hero-grid{
  max-width:880px;
  padding-top:clamp(48px,7vw,104px);
  padding-bottom:clamp(32px,5vw,64px);
}
.hero-mark{width:44px;height:12px;background:var(--ikb);margin-bottom:clamp(24px,3.5vw,44px)}
h1{
  font-size:clamp(32px,5vw,60px);
  font-weight:600;
  line-height:1.22;
  letter-spacing:.01em;
  margin-bottom:clamp(22px,3vw,36px);
}
.hero-sub{
  font-size:clamp(15px,1.4vw,18px);
  color:var(--gray);
  max-width:34em;
  margin-bottom:clamp(30px,4vw,48px);
}
.hero-grid .hero-sub{margin-bottom:0}
.hero-cta{display:flex;flex-wrap:wrap;gap:16px 28px;align-items:center}
.btn{
  display:inline-block;background:var(--ikb);color:#fff;
  font-size:15px;font-weight:600;letter-spacing:.03em;
  padding:15px 30px;
  transition:background .2s,transform .2s;
}
.btn:hover{background:var(--ikb-deep)}
.link-arrow{
  font-size:15px;font-weight:600;color:var(--ink);
  border-bottom:2px solid var(--ink);padding-bottom:3px;
  transition:color .2s,border-color .2s;
}
.link-arrow:hover{color:var(--ikb);border-bottom-color:var(--ikb)}
.hero-photo{position:relative}
.hero-photo img{width:100%;height:auto;aspect-ratio:4/5;object-fit:cover}
.hero-photo figcaption{
  font-family:var(--mono);font-size:11px;color:var(--gray);
  letter-spacing:.1em;margin-top:12px;display:flex;justify-content:space-between;gap:12px;
}
@media (max-width:840px){
  .hero-grid{padding-top:44px;padding-bottom:40px}
  .hero-photo{max-width:440px}
}
.hero-facts{
  display:grid;grid-template-columns:repeat(4,minmax(0,1fr));gap:16px 32px;
  border-top:1px solid var(--line);
  padding-top:24px;padding-bottom:clamp(32px,4.5vw,56px);
}
.hero-facts .k{font-family:var(--mono);font-size:11px;letter-spacing:.18em;color:var(--gray);display:block;margin-bottom:4px}
.hero-facts b{font-size:15px;font-weight:600}
@media (max-width:840px){.hero-facts{grid-template-columns:repeat(2,minmax(0,1fr))}}
@media (max-width:560px){.hero-facts{grid-template-columns:1fr;gap:14px}}

/* ============ sections ============ */
.sec{padding-top:var(--sec-y);padding-bottom:var(--sec-y);position:relative}
.sec::before{
  content:"";position:absolute;top:0;
  left:calc(max((100% - var(--wrap-max))/2, 0px) + var(--pad-x));
  right:calc(max((100% - var(--wrap-max))/2, 0px) + var(--pad-x));
  border-top:1px solid var(--line);
}
.sec-alt{background:var(--paper-2)}
.sec-head{margin-bottom:clamp(36px,5vw,64px)}
.eyebrow{
  font-family:var(--mono);font-size:12px;letter-spacing:.22em;
  color:var(--ikb);font-weight:500;display:block;margin-bottom:14px;
}
h2{
  font-size:clamp(28px,3.8vw,46px);
  font-weight:600;line-height:1.3;letter-spacing:.01em;
}
.sec-note{font-size:14px;color:var(--gray);margin-top:12px}
strong{font-weight:600;color:var(--ikb)}

/* ---- about ---- */
.about-hero{
  display:grid;grid-template-columns:minmax(240px,.8fr) minmax(0,1.2fr);
  gap:clamp(32px,6vw,88px);align-items:end;
  margin-bottom:clamp(44px,6vw,76px);
}
.about-hero .sec-head{margin-bottom:clamp(4px,1vw,16px)}
.about-portrait{max-width:480px}
.about-grid{display:grid;grid-template-columns:minmax(0,2fr) minmax(0,1fr);gap:clamp(32px,6vw,88px)}
.about-body p{margin-bottom:1.4em;max-width:38em}
.about-body p:last-child{margin-bottom:0}
.about-side{border-left:1px solid var(--line);padding-left:clamp(20px,2.5vw,36px);align-self:start}
.about-side dl{display:grid;gap:22px}
.about-side dt{font-family:var(--mono);font-size:11px;letter-spacing:.18em;color:var(--gray);margin-bottom:4px}
.about-side dd{font-size:15px;font-weight:600;line-height:1.6}
@media (max-width:840px){
  .about-hero{grid-template-columns:1fr;align-items:start}
  .about-grid{grid-template-columns:1fr}
  .about-side{border-left:none;border-top:1px solid var(--line);padding-left:0;padding-top:28px}
}

/* ---- now ---- */
.now-grid{display:grid;grid-template-columns:repeat(3,1fr);gap:1px;background:var(--line);border:1px solid var(--line)}
.now-item{background:var(--paper);padding:clamp(20px,2.5vw,32px)}
.now-item h3{font-size:16px;font-weight:600;margin-bottom:8px}
.now-item p{font-size:14px;color:var(--gray);line-height:1.75}
.now-item .status{display:inline-flex;align-items:center;gap:8px;font-family:var(--mono);font-size:11px;letter-spacing:.16em;color:var(--ikb);margin-bottom:12px}
.now-item .status i{width:8px;height:8px;border-radius:50%;background:var(--ikb);animation:pulse 2.4s ease-in-out infinite}
@keyframes pulse{0%,100%{opacity:1}50%{opacity:.3}}
@media (max-width:1000px){.now-grid{grid-template-columns:repeat(2,1fr)}}
@media (max-width:560px){.now-grid{grid-template-columns:1fr}}

/* ---- business ---- */
.biz-grid{display:grid;grid-template-columns:1fr 1fr;gap:1px;background:var(--line);border:1px solid var(--line)}
.biz-card{
  background:var(--paper);padding:clamp(24px,3.2vw,44px);
  display:flex;flex-direction:column;gap:16px;
  transition:background .25s;position:relative;
}
.biz-card::before{
  content:"";position:absolute;top:0;left:0;width:0;height:3px;background:var(--ikb);
  transition:width .3s ease;
}
.biz-card:hover::before{width:100%}
.biz-tag{font-family:var(--mono);font-size:11px;letter-spacing:.2em;color:var(--gray)}
.biz-card h3{font-size:clamp(19px,1.8vw,23px);font-weight:600;line-height:1.45}
.biz-card .price{font-family:var(--mono);font-size:13px;color:var(--ikb);font-weight:600}
.biz-card p{font-size:15px;line-height:1.85;color:var(--ink)}
.biz-aud{font-size:14px;color:var(--gray);border-top:1px solid var(--line);padding-top:14px;margin-top:auto}
@media (min-width:841px){.biz-aud{min-height:78px}}
.biz-aud b{font-weight:600;color:var(--ink)}
.biz-cta{margin-top:0}
.biz-cta a{
  font-size:14px;font-weight:600;color:var(--ikb);
  border-bottom:1.5px solid transparent;transition:border-color .2s;
}
.biz-cta a:hover{border-bottom-color:var(--ikb)}
@media (max-width:840px){.biz-grid{grid-template-columns:1fr}}
.ladder{
  margin-top:clamp(32px,4vw,52px);
  border-left:4px solid var(--ikb);
  padding:6px 0 6px clamp(18px,2.5vw,30px);
  max-width:44em;
}
.ladder p{font-size:clamp(15px,1.35vw,17px);line-height:1.9}

/* ---- open source ---- */
.oss-group{margin-bottom:clamp(36px,5vw,64px)}
.oss-group:last-child{margin-bottom:0}
.oss-group-title{
  font-family:var(--mono);font-size:12px;letter-spacing:.2em;font-weight:500;
  color:var(--gray);margin-bottom:4px;
}
.oss-group-note{font-size:14px;color:var(--gray);line-height:1.8;margin-bottom:18px;max-width:56em}
.oss-grid{display:grid;grid-template-columns:1fr 1fr;gap:1px;background:var(--line);border:1px solid var(--line)}
.oss-card{background:var(--paper-2);padding:clamp(22px,2.8vw,36px);transition:background .25s;display:block}
.oss-card:hover{background:#fff}
.oss-card h3{
  font-size:17px;font-weight:600;letter-spacing:.01em;
  margin-bottom:10px;display:flex;align-items:baseline;gap:8px;
}
.shelf-tag{font-family:var(--mono);font-size:10px;letter-spacing:.16em;color:var(--gray);display:block;margin-bottom:10px}
.oss-card h3 .ext{font-size:13px;color:var(--ikb);transition:transform .2s;display:inline-block}
.oss-card:hover h3 .ext{transform:translate(2px,-2px)}
.oss-card p{font-size:14px;color:var(--gray);line-height:1.8}
@media (max-width:640px){.oss-grid{grid-template-columns:1fr}}

/* ---- articles ---- */
.art-group{margin-bottom:clamp(32px,4.5vw,52px)}
.art-group:last-of-type{margin-bottom:0}
.art-group-title{
  font-family:var(--mono);font-size:12px;letter-spacing:.2em;font-weight:500;
  color:var(--gray);margin-bottom:4px;
}
.art-list{border-top:1px solid var(--line)}
.art-row{padding:15px 0;border-bottom:1px solid var(--line)}
.art-title{font-size:clamp(15px,1.35vw,16.5px);font-weight:500;line-height:1.65}
.art-title a{border-bottom:1.5px solid transparent;transition:color .2s,border-color .2s}
.art-title a:hover{color:var(--ikb);border-bottom-color:var(--ikb)}
.art-title .ext{font-size:13px;color:var(--ikb);margin-left:4px}
.art-more{margin-top:24px;font-size:14px;color:var(--gray)}

/* ---- contact (signature IKB block) ---- */
.contact{background:var(--ikb);color:#fff;border-top:none}
.on-ikb strong{color:#fff;border-bottom:2px solid rgba(255,255,255,.6)}
.contact .eyebrow{color:rgba(255,255,255,.75)}
.contact-grid{
  display:grid;grid-template-columns:minmax(0,1.2fr) minmax(0,.8fr);
  gap:clamp(36px,6vw,88px);align-items:start;
}
.contact-lead{font-size:clamp(22px,3vw,34px);font-weight:600;line-height:1.5;margin-bottom:20px}
.contact-body{font-size:clamp(15px,1.35vw,17px);line-height:1.9;color:rgba(255,255,255,.88);max-width:32em;margin-bottom:36px}
.contact-list{display:grid;gap:0;border-top:1px solid rgba(255,255,255,.28)}
.contact-list li{
  display:grid;grid-template-columns:110px minmax(0,1fr);gap:16px;align-items:baseline;
  padding:14px 0;border-bottom:1px solid rgba(255,255,255,.28);
}
.contact-list .k{font-family:var(--mono);font-size:12px;letter-spacing:.16em;color:rgba(255,255,255,.82)}
.contact-list .v{font-size:15px;font-weight:600;overflow-wrap:anywhere}
.contact-list .v a{border-bottom:1.5px solid rgba(255,255,255,.5);transition:border-color .2s}
.contact-list .v a:hover{border-bottom-color:#fff}
.qr-card{background:#fff;color:var(--ink);padding:clamp(20px,2.5vw,32px);max-width:340px;justify-self:end}
.qr-card img{width:100%;height:auto}
.qr-card figcaption{
  margin-top:16px;font-size:14px;font-weight:600;text-align:center;letter-spacing:.05em;
}
.qr-card figcaption small{display:block;font-family:var(--mono);font-weight:400;font-size:11px;color:var(--gray);letter-spacing:.14em;margin-top:4px}
@media (max-width:840px){
  .contact-grid{grid-template-columns:1fr}
  .qr-card{justify-self:start}
  .contact-list li{grid-template-columns:96px minmax(0,1fr)}
}

/* ---- footer ---- */
.footer{padding:36px 0 44px;background:var(--paper);position:relative}
.footer::before{
  content:"";position:absolute;top:0;
  left:calc(max((100% - var(--wrap-max))/2, 0px) + var(--pad-x));
  right:calc(max((100% - var(--wrap-max))/2, 0px) + var(--pad-x));
  border-top:1px solid var(--line);
}
.footer-inner{display:flex;flex-wrap:wrap;gap:10px 32px;justify-content:space-between;align-items:baseline}
.footer .copy{font-size:14px;font-weight:600}
.footer .disclaimer{font-size:12px;color:var(--gray)}

/* 单卡分组不留空槽 */
.oss-grid:has(> .oss-card:only-child){grid-template-columns:1fr}

/* 关于我分点 */
.about-points{list-style:none;margin:0 0 1.4em;max-width:40em}
.about-points li{margin-bottom:1.05em;line-height:1.9;padding-left:26px;position:relative}
.about-points li::before{content:"";position:absolute;left:0;top:.72em;width:14px;height:3px;background:var(--ikb)}
/* hero 数字条公众号轻链接 */
.hero-facts a{display:block;transition:opacity .2s}
.hero-facts a:hover b{color:var(--ikb)}
.hero-facts a .ext{font-size:12px;color:var(--ikb)}
/* 文章库:标题一行,观点句换行跟随 */
.art-hook{font-size:14px;color:var(--gray);line-height:1.75;margin-top:4px;max-width:44em}
/* 首页公众号轻入口 */
.hero-gzh{font-size:14px;color:var(--gray);margin-top:14px}
.hero-gzh a{border-bottom:1px solid transparent;transition:border-color .2s}
.hero-gzh a b{color:var(--ikb);font-weight:600}
.hero-gzh a:hover{border-bottom-color:var(--ikb)}

/* 公众号扫码弹窗 */
.qrm-modal{position:fixed;inset:0;z-index:200;display:none}
.qrm-modal.open{display:block}
.qrm-mask{position:absolute;inset:0;background:rgba(16,16,16,.52)}
.qrm-card{
  position:absolute;top:50%;left:50%;transform:translate(-50%,-50%);
  background:#fff;color:var(--ink);padding:34px 40px 26px;text-align:center;
  box-shadow:0 24px 64px rgba(0,0,0,.22);
}
.qrm-card img{width:220px;height:auto;margin:0 auto;display:block}
.qrm-name{font-weight:600;font-size:16px;margin-top:14px}
.qrm-card .qrm-tip{font-family:var(--mono);font-size:11px;letter-spacing:.18em;color:var(--gray);margin-top:4px}
.qrm-close{
  position:absolute;top:6px;right:12px;background:none;border:none;
  font-size:24px;line-height:1;color:var(--gray);cursor:pointer;padding:4px;
}
.qrm-close:hover{color:var(--ink)}
/* 标签之外的我 */
.about-life{margin-top:clamp(44px,6vw,72px);border-top:1px solid var(--line);padding-top:clamp(28px,4vw,44px)}
.about-life-title{font-size:18px;font-weight:600;margin-bottom:8px}
.about-life-lead{font-size:15px;color:var(--gray);margin-bottom:22px}
.about-life-list{display:grid;gap:16px;max-width:44em}
.about-life-list dt{font-family:var(--mono);font-size:11px;letter-spacing:.18em;color:var(--gray);margin-bottom:2px}
.about-life-list dd{font-size:15px;font-weight:500}

/* ---- 小白入门（首页开源区顶部） ---- */
.skill-intro{border:1px solid var(--line);background:var(--paper-2);padding:clamp(24px,3vw,36px);margin-bottom:clamp(36px,4.5vw,52px)}
.skill-intro-title{font-size:18px;font-weight:600;margin-bottom:10px}
.skill-intro-lead{font-size:15px;color:var(--ink);line-height:1.85;margin-bottom:22px;max-width:46em}
.skill-intro-steps{display:grid;gap:14px}
.skill-intro-steps li{display:flex;gap:13px;align-items:flex-start;font-size:14.5px;color:var(--gray);line-height:1.7}
.skill-intro-steps li b{flex:none;width:24px;height:24px;border-radius:50%;background:var(--ikb);color:#fff;font-size:13px;font-weight:600;display:flex;align-items:center;justify-content:center;margin-top:1px}
@media(min-width:720px){.skill-intro-steps{grid-template-columns:repeat(3,1fr);gap:24px}}

/* ---- 首页收尾·下一步 ---- */
.home-next>p{font-size:16px;font-weight:600;margin-bottom:18px}
.home-next-links{display:flex;flex-wrap:wrap;gap:14px 32px}
.home-next-links a{font-size:15px;font-weight:600;color:var(--ikb);border-bottom:1.5px solid transparent;transition:border-color .2s}
.home-next-links a:hover{border-bottom-color:var(--ikb)}

/* ---- Now 卡内详情链接 ---- */
.now-link{display:inline-block;margin-top:12px;font-size:13px;font-weight:600;color:var(--ikb);border-bottom:1.5px solid transparent;transition:border-color .2s}
.now-link:hover{border-bottom-color:var(--ikb)}

/* ---- 关于我尾句 CTA ---- */
.about-cta-link{display:inline-block;margin-top:14px;font-size:15px;font-weight:600;color:var(--ikb);border-bottom:2px solid var(--ikb)}

/* ---- 三档深度（业务页） ---- */
.depth-grid{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:1px;background:var(--line);border:1px solid var(--line)}
.depth-grid .biz-card{background:var(--paper)}
@media (max-width:960px){.depth-grid{grid-template-columns:1fr}}
.biz-grid-single{grid-template-columns:minmax(0,1fr)}
@media (min-width:841px){.biz-grid-single{grid-template-columns:minmax(0,.62fr)}}

/* hero 署名行（三标签版） */
.hero-byline{display:flex;align-items:flex-start;gap:14px;margin-bottom:clamp(22px,3vw,32px)}
.hero-byline img{width:44px;height:44px;border-radius:50%;object-fit:cover;object-position:center 20%;flex:none}
.hero-byline-name{font-size:15px;color:var(--ink);margin-bottom:8px;line-height:1.5}
.hero-byline-name b{font-weight:600}
.hero-byline-name a{color:var(--ikb);font-weight:600;border-bottom:1.5px solid transparent;transition:border-color .2s}
.hero-byline-name a:hover{border-bottom-color:var(--ikb)}
.hero-byline-tags{display:flex;flex-wrap:wrap;gap:8px}
.hero-byline-tags span{font-size:12.5px;color:var(--gray);border:1px solid var(--line);padding:3px 10px;line-height:1.6;white-space:nowrap}