*,*::before,*::after{box-sizing:border-box;margin:0;padding:0}
html{scroll-behavior:smooth}
body{font-family:"Noto Sans SC",system-ui,sans-serif;background:#fff;color:#1a1a1a;line-height:1.76;font-size:16px}
a{color:#0891b2;text-decoration:none}
a:hover{text-decoration:underline}
img{max-width:100%;height:auto;display:block}

.site-header{background:#fff;border-bottom:2px solid #cffafe;position:sticky;top:0;z-index:200}
.header-inner{max-width:960px;margin:0 auto;padding:0 20px;display:flex;align-items:center;justify-content:space-between;position:relative}
.brand{display:flex;align-items:center;gap:10px;color:#1a1a1a;font-weight:500;font-size:.95rem}
.brand em{font-style:normal;color:#0e7490;font-weight:700}
.site-nav ul{display:flex;gap:18px;list-style:none;flex-wrap:wrap}
.site-nav a{color:#555;font-size:.9rem;padding:18px 0;display:block}
.site-nav a.active,.site-nav a:hover{color:#0e7490;font-weight:600;text-decoration:none}
.nav-toggle{display:none;background:none;border:none;cursor:pointer;padding:8px;flex-direction:column;gap:5px}
.nav-toggle span{display:block;width:22px;height:2px;background:#333;transition:transform .2s}
.nav-toggle.is-open span:nth-child(1){transform:translateY(7px) rotate(45deg)}
.nav-toggle.is-open span:nth-child(2){opacity:0}
.nav-toggle.is-open span:nth-child(3){transform:translateY(-7px) rotate(-45deg)}

.ads-top-bar{background:#ecfeff;border-bottom:1px solid #cffafe;padding:10px 0}
.applist-title{font-size:.78rem;color:#888;text-align:center;margin-bottom:6px}
#ads{display:flex;justify-content:center;flex-wrap:wrap;gap:12px}

.timeline-wrap{max-width:960px;margin:0 auto;padding:0 20px 52px;position:relative}
.timeline-wrap::before{content:"";position:absolute;left:50%;top:200px;bottom:40px;width:3px;background:linear-gradient(#0891b2,#67e8f9);transform:translateX(-50%)}
.timeline-hero{padding:36px 0 48px;text-align:center;scroll-margin-top:80px}
.timeline-hero .tag{display:inline-block;font-size:.72rem;color:#0e7490;border:1px solid #67e8f9;background:#ecfeff;padding:4px 12px;border-radius:20px;margin-bottom:14px}
.timeline-hero h1{font-size:1.68rem;line-height:1.34;margin-bottom:16px;color:#111;max-width:780px;margin-left:auto;margin-right:auto}
.timeline-hero .lede{color:#333;text-align:justify;max-width:760px;margin:0 auto}

.timeline-item{position:relative;padding:32px 0;display:flex;scroll-margin-top:80px}
.timeline-item.left{justify-content:flex-end;padding-right:calc(50% + 28px)}
.timeline-item.right{justify-content:flex-start;padding-left:calc(50% + 28px)}
.tl-marker{position:absolute;left:50%;top:40px;width:16px;height:16px;background:#0891b2;border:3px solid #ecfeff;border-radius:50%;transform:translateX(-50%);z-index:2}
.tl-content{max-width:420px;padding:24px;background:#fff;border:1px solid #a5f3fc;border-radius:12px;box-shadow:0 2px 8px rgba(8,145,178,.08)}
.tl-content h2{font-size:1.12rem;margin-bottom:12px;color:#155e75}
.tl-content p{margin-bottom:10px;text-align:justify;color:#333;font-size:.95rem}
.tl-content figure{margin:14px 0;border-radius:8px;overflow:hidden}
.tl-content figcaption{font-size:.78rem;color:#666;padding:6px 10px;background:#ecfeff}
.closing-note{margin-top:18px;padding:16px;background:#ecfeff;border-radius:8px;border-left:4px solid #0891b2}
.closing-note h3{font-size:.95rem;margin-bottom:8px}
.closing-note p{font-size:.9rem;color:#444}

.site-footer{background:#ecfeff;border-top:1px solid #cffafe;padding:28px 20px;text-align:center;font-size:.88rem;color:#666}
.footer-links{display:flex;flex-wrap:wrap;justify-content:center;gap:14px;margin-bottom:10px}
.footer-sub{font-size:.8rem;color:#999;margin-top:4px}
.prose-page{max-width:760px;margin:0 auto;padding:32px 20px 48px}
.prose-page h1{font-size:1.45rem;margin-bottom:16px}
.prose-page p{margin-bottom:12px;color:#333}

@media(max-width:720px){
  .timeline-wrap::before{left:20px}
  .timeline-item.left,.timeline-item.right{justify-content:flex-start;padding-left:48px;padding-right:0}
  .tl-marker{left:20px}
  .tl-content{max-width:100%}
  .nav-toggle{display:flex}
  .site-nav{display:none;position:absolute;top:100%;left:0;right:0;background:#fff;border-bottom:1px solid #eee;padding:12px 20px;box-shadow:0 4px 12px rgba(0,0,0,.06)}
  .site-nav.is-open{display:block}
  .site-nav ul{flex-direction:column;gap:0}
}