/* 青云梯 QINGYUN ASCEND —— 蓝白品牌视觉 */
:root{
  --blue-900:#0b2a5b;--blue-800:#103a7c;--blue-700:#1557b8;--blue-600:#1d6fe0;--blue-500:#3b8bf5;
  --blue-200:#bfe0ff;--blue-100:#e3f0ff;--blue-50:#f3f8ff;
  --ink:#0f1f38;--ink-2:#41526d;--muted:#6b7a92;--line:#d9e5f5;--white:#fff;
  --amber:#b4560a;--amber-bg:#fff4e6;
  --radius:16px;--shadow:0 10px 30px -14px rgba(16,58,124,.35);
  --font:"PingFang SC","Hiragino Sans GB","Microsoft YaHei","Noto Sans SC","Source Han Sans SC",system-ui,-apple-system,"Segoe UI",sans-serif;
}
*,*::before,*::after{box-sizing:border-box}
html{-webkit-text-size-adjust:100%;scroll-behavior:smooth;scroll-padding-top:80px}
body{margin:0;font-family:var(--font);color:var(--ink);background:var(--white);line-height:1.75;font-size:16px;overflow-x:hidden}
img,svg{max-width:100%}
a{color:var(--blue-700);text-underline-offset:3px}
a:hover{color:var(--blue-600)}
h1,h2,h3{line-height:1.3;margin:0 0 .6em;letter-spacing:.01em}
h2{font-size:clamp(1.5rem,3.2vw,2.1rem)}
h3{font-size:1.15rem}
p{margin:0 0 1em}
code{background:var(--blue-100);color:var(--blue-800);padding:.1em .45em;border-radius:6px;font-size:.92em}
.wrap{width:100%;max-width:1160px;margin:0 auto;padding:0 16px}
.narrow{max-width:820px}
.center{text-align:center}
.mt{margin-top:2em}
.muted{color:var(--muted)}
.tiny{font-size:.8rem;color:var(--muted);margin:.6em 0 0}
.sr{position:absolute;width:1px;height:1px;overflow:hidden;clip:rect(0 0 0 0)}
.skip{position:absolute;left:-999px;top:8px;background:#fff;padding:8px 12px;z-index:100}
.skip:focus{left:8px}

/* buttons */
.btn{display:inline-flex;align-items:center;justify-content:center;gap:.4em;padding:.75em 1.4em;border-radius:999px;font-weight:600;text-decoration:none;border:1.5px solid transparent;transition:.18s;white-space:nowrap;line-height:1.2;font-size:1rem}
.btn-sm{padding:.5em 1em;font-size:.9rem}
.btn-block{display:flex;width:100%}
.btn-primary{background:var(--blue-600);color:#fff}
.btn-primary:hover{background:var(--blue-700);color:#fff}
.btn-outline{border-color:var(--blue-600);color:var(--blue-700);background:#fff}
.btn-outline:hover{background:var(--blue-50)}
.btn-white{background:#fff;color:var(--blue-700)}
.btn-white:hover{background:var(--blue-100);color:var(--blue-800)}
.btn-ghost{border-color:rgba(255,255,255,.6);color:#fff}
.btn-ghost:hover{background:rgba(255,255,255,.12);color:#fff}
.btn-light{background:#fff;color:var(--blue-800)}

/* header */
.site-header{position:sticky;top:0;z-index:50;background:rgba(255,255,255,.94);backdrop-filter:blur(10px);border-bottom:1px solid var(--line)}
.header-inner{display:flex;align-items:center;justify-content:space-between;height:64px;gap:16px}
.brand{display:flex;align-items:center;gap:10px;text-decoration:none;color:var(--ink);flex-shrink:0}
.logo-mark{width:36px;height:36px;flex-shrink:0}
.brand-text{display:flex;flex-direction:column;line-height:1.1}
.brand-text b{font-size:1.15rem}
.brand-text small{font-size:.62rem;letter-spacing:.22em;color:var(--blue-600);font-weight:600}
.site-nav{display:flex;align-items:center;gap:4px}
.site-nav a:not(.btn){color:var(--ink-2);text-decoration:none;padding:.45em .75em;border-radius:8px;font-size:.95rem}
.site-nav a:not(.btn):hover,.site-nav a[aria-current]{color:var(--blue-700);background:var(--blue-50)}
.site-nav .btn{margin-left:8px}
.nav-toggle,.nav-burger{display:none}
@media (max-width:900px){
  .nav-burger{display:flex;flex-direction:column;gap:5px;cursor:pointer;padding:10px}
  .nav-burger span{width:22px;height:2px;background:var(--ink);border-radius:2px}
  .site-nav{position:absolute;left:0;right:0;top:64px;flex-direction:column;align-items:stretch;background:#fff;border-bottom:1px solid var(--line);padding:8px 16px 16px;display:none;box-shadow:var(--shadow)}
  .nav-toggle:checked~.site-nav{display:flex}
  .site-nav a:not(.btn){padding:.75em .5em;border-bottom:1px solid var(--blue-50)}
  .site-nav .btn{margin:12px 0 0}
}

/* hero */
.hero{position:relative;color:#fff;background:radial-gradient(1200px 500px at 85% -10%,#5aa8ff 0,transparent 60%),linear-gradient(135deg,var(--blue-800),var(--blue-600));padding:72px 0 120px;overflow:hidden}
.hero::before{content:"";position:absolute;inset:0;background-image:repeating-linear-gradient(90deg,rgba(255,255,255,.06) 0 2px,transparent 2px 120px);mask-image:linear-gradient(transparent,#000 30%,transparent)}
.hero-inner{position:relative;display:grid;grid-template-columns:1.25fr 1fr;gap:48px;align-items:center}
.kicker{font-size:.78rem;letter-spacing:.24em;font-weight:700;color:var(--blue-600);margin:0 0 .6em;text-transform:uppercase}
.kicker-light{color:var(--blue-200)}
.hero h1{font-size:clamp(2.4rem,6vw,4rem);margin-bottom:.35em}
.hero h1 span{display:block;font-size:.42em;font-weight:500;letter-spacing:.3em;color:var(--blue-200);margin-top:.5em}
.hero-lead{font-size:1.1rem;color:#e6f1ff;max-width:34em}
.hero-lead b{color:#fff}
.hero-cta{display:flex;flex-wrap:wrap;gap:12px;margin-top:1.6em}
.hero-stats{list-style:none;margin:0;padding:0;display:grid;grid-template-columns:1fr 1fr;gap:12px}
.hero-stats li{background:rgba(255,255,255,.1);border:1px solid rgba(255,255,255,.22);border-radius:var(--radius);padding:18px;backdrop-filter:blur(4px)}
.hero-stats b{display:block;font-size:1.6rem;line-height:1.2}
.hero-stats b small{font-size:.55em;font-weight:500;opacity:.85}
.hero-stats span{font-size:.85rem;color:var(--blue-100)}
.hero-cloud{position:absolute;bottom:-1px;left:0;width:100%;height:70px}

/* sections */
.section{padding:72px 0}
.section-tight{padding:24px 0 72px}
.section-alt{background:var(--blue-50)}
.lead{color:var(--ink-2);font-size:1.05rem;max-width:46em}
.group-h{display:flex;align-items:center;gap:10px;font-size:1rem;color:var(--blue-800);margin:2.2em 0 1em;letter-spacing:.06em}
.group-h span{display:inline-grid;place-items:center;width:30px;height:30px;border-radius:50%;background:var(--blue-100);color:var(--blue-700);font-size:.8rem}
.page-head{padding:40px 0 8px}
.page-head h1{font-size:clamp(1.9rem,4.5vw,2.8rem)}
.page-cta{display:flex;flex-wrap:wrap;gap:12px}
.crumbs{font-size:.85rem;color:var(--muted);padding-top:20px}
.crumbs a{color:var(--muted)}

/* plan cards */
.tag{display:inline-block;font-size:.75rem;font-weight:700;padding:.2em .7em;border-radius:999px;margin-bottom:.6em;letter-spacing:.05em}
.tag-annual{background:var(--blue-100);color:var(--blue-700)}
.tag-custom{background:rgba(255,255,255,.18);color:#fff}
.spec{list-style:none;padding:0;margin:0;display:flex;flex-wrap:wrap;gap:10px 28px}
.spec li{display:flex;flex-direction:column}
.spec span{font-size:.8rem;color:var(--muted)}
.spec b{font-size:1.1rem}

.mini-card{display:grid;grid-template-columns:1.3fr 1fr;border:2px solid var(--blue-500);border-radius:20px;overflow:hidden;box-shadow:var(--shadow);background:#fff}
.mini-left{padding:28px}
.mini-left h3{font-size:1.5rem}
.mini-fit{color:var(--ink-2)}
.mini-right{background:linear-gradient(160deg,var(--blue-50),var(--blue-100));padding:28px;display:flex;flex-direction:column;justify-content:center}
.big-price{font-size:3.4rem;font-weight:800;color:var(--blue-700);line-height:1;margin:0 0 .25em;letter-spacing:-.02em}
.big-price .cur{font-size:.45em;vertical-align:.7em;margin-right:2px}
.big-price .per{font-size:.38em;font-weight:600;color:var(--ink-2)}
.equiv{color:var(--ink-2);font-size:.92rem;margin-bottom:1.1em}

.vip-grid{display:grid;grid-template-columns:repeat(4,minmax(0,1fr));gap:16px}
.vip-card{display:flex;flex-direction:column;border:1px solid var(--line);border-radius:var(--radius);padding:22px;background:#fff;transition:.2s}
.vip-card:hover{border-color:var(--blue-500);box-shadow:var(--shadow);transform:translateY(-2px)}
.vip-card header{border-bottom:1px dashed var(--line);margin-bottom:14px}
.vip-card h3{margin-bottom:.2em}
.vip-traffic{font-size:2rem;font-weight:800;color:var(--blue-700);margin:0 0 .4em;line-height:1.1}
.vip-traffic small{font-size:.45em;font-weight:600;color:var(--muted);margin-left:3px}
.price-pair{display:grid;grid-template-columns:1fr 1fr;gap:8px;margin:0 0 14px}
.price-pair div{border-radius:10px;padding:10px 12px}
.pp-month{background:var(--blue-600);color:#fff}
.pp-year{background:var(--blue-50);color:var(--blue-800)}
.price-pair dt{font-size:.75rem;opacity:.85}
.price-pair dd{margin:0;font-weight:800;font-size:1.25rem}
.price-pair dd small{font-size:.65em;font-weight:500}
.vip-fit{color:var(--ink-2);font-size:.93rem;flex-grow:1}
.caveat{font-size:.82rem;color:var(--amber);background:var(--amber-bg);border-radius:8px;padding:6px 10px}

.custom-card{margin-top:4px;display:grid;grid-template-columns:1.4fr auto auto;gap:24px;align-items:center;border-radius:20px;padding:28px;color:#fff;background:linear-gradient(120deg,var(--blue-900),var(--blue-700))}
.custom-card h3{font-size:1.4rem}
.custom-card p{color:var(--blue-100);margin:0}
.custom-card .spec span{color:var(--blue-200)}
.custom-cta .tiny{color:var(--blue-200)}

/* compare table */
.table-wrap{border:1px solid var(--line);border-radius:var(--radius);overflow:hidden;background:#fff}
.compare{width:100%;border-collapse:collapse;font-size:.95rem}
.compare caption{caption-side:bottom;text-align:left;padding:10px 16px;font-size:.8rem;color:var(--muted)}
.compare th,.compare td{padding:14px 16px;text-align:left;border-bottom:1px solid var(--line);vertical-align:middle}
.compare thead th{background:var(--blue-50);font-size:.85rem;color:var(--blue-800)}
.compare tbody th a{font-weight:700;text-decoration:none}
.compare small{color:var(--muted)}
.compare .row-annual{background:#fbfdff}
.compare .row-custom{background:var(--blue-50)}
.td-cta{text-align:right}
@media (max-width:760px){
  .table-wrap{border:0;background:none}
  .compare thead{display:none}
  .compare,.compare tbody,.compare tr,.compare th,.compare td{display:block;width:100%}
  .compare tr{border:1px solid var(--line);border-radius:14px;margin-bottom:12px;background:#fff;overflow:hidden}
  .compare tbody th{background:var(--blue-50);font-size:1.05rem}
  .compare td{display:flex;justify-content:space-between;gap:12px;text-align:right;padding:10px 16px}
  .compare td::before{content:attr(data-label);color:var(--muted);text-align:left;flex-shrink:0}
  .compare td.td-cta{display:block;border-bottom:0}
  .compare td.td-cta .btn{width:100%}
  .compare caption{display:block;width:100%;padding:0 0 10px}
  .compare td>span{display:flex;flex-direction:column;align-items:flex-end}
}

.notes-grid{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:16px;margin-top:24px}
.note{background:#fff;border:1px solid var(--line);border-radius:var(--radius);padding:20px}
.note h3{font-size:1rem;color:var(--blue-800)}
.note p{margin:0;color:var(--ink-2);font-size:.93rem}

.steps{padding-left:1.2em;max-width:52em}
.steps li{margin-bottom:.8em}

/* posts */
.post-grid{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:16px}
.post-card{display:block;background:#fff;border:1px solid var(--line);border-radius:var(--radius);padding:22px;text-decoration:none;color:var(--ink);transition:.2s}
.post-card:hover{border-color:var(--blue-500);box-shadow:var(--shadow);color:var(--ink)}
.post-card time{font-size:.8rem;color:var(--muted)}
.post-card h3{margin:.3em 0 .4em;color:var(--blue-800)}
.post-card p{color:var(--ink-2);font-size:.92rem;margin:0}
.link-more{font-weight:600;text-decoration:none;display:inline-block;margin-top:20px}
.link-list{padding-left:1.1em}
.link-list li{margin-bottom:.5em}

/* article */
.article{padding-top:24px;padding-bottom:72px}
.article h1{font-size:clamp(1.7rem,4.2vw,2.4rem)}
.meta{color:var(--muted);font-size:.9rem}
.prose{font-size:1.05rem}
.prose h2{font-size:1.35rem;margin-top:1.8em;padding-left:12px;border-left:4px solid var(--blue-600)}
.prose ul{padding-left:1.2em}
.prose li{margin-bottom:.4em}
.article-cta{margin-top:2em}
.related{margin-top:48px;padding:24px;border-radius:var(--radius);background:var(--blue-50)}
.related h2{font-size:1.1rem}

/* faq */
.faq details{border:1px solid var(--line);border-radius:12px;margin-bottom:10px;background:#fff}
.faq summary{cursor:pointer;padding:16px 44px 16px 18px;font-weight:600;list-style:none;position:relative}
.faq summary::-webkit-details-marker{display:none}
.faq summary::after{content:"+";position:absolute;right:18px;top:50%;transform:translateY(-50%);font-size:1.3rem;color:var(--blue-600)}
.faq details[open] summary::after{content:"−"}
.faq details p{padding:0 18px 16px;margin:0;color:var(--ink-2)}

/* cta + footer */
.cta-band{background:linear-gradient(120deg,var(--blue-700),var(--blue-500));color:#fff;padding:56px 0}
.cta-inner{display:flex;align-items:center;justify-content:space-between;gap:24px;flex-wrap:wrap}
.cta-inner h2{margin-bottom:.3em}
.cta-inner p{margin:0;color:var(--blue-100)}
.site-footer{background:var(--blue-900);color:var(--blue-100);padding:48px 0 24px;font-size:.92rem}
.site-footer a{color:var(--blue-100);text-decoration:none}
.site-footer a:hover{color:#fff}
.footer-grid{display:grid;grid-template-columns:1.6fr 1fr 1fr;gap:32px}
.footer-brand{display:flex;gap:12px;align-items:center}
.footer-brand small{color:var(--blue-200);letter-spacing:.08em}
.footer-h{font-size:.95rem;color:#fff}
.footer-links{list-style:none;padding:0;margin:0}
.footer-links li{margin-bottom:.4em}
.site-footer .muted{color:var(--blue-200)}
.copyright{border-top:1px solid rgba(255,255,255,.12);margin-top:32px;padding-top:18px;font-size:.8rem;color:var(--blue-200)}

/* responsive */
@media (max-width:1000px){
  .vip-grid{grid-template-columns:repeat(2,minmax(0,1fr))}
  .custom-card{grid-template-columns:1fr}
}
@media (max-width:760px){
  .hero{padding:48px 0 96px}
  .hero-inner{grid-template-columns:1fr;gap:32px}
  .hero h1 span{letter-spacing:.16em}
  .section{padding:52px 0}
  .mini-card{grid-template-columns:1fr}
  .notes-grid,.post-grid,.footer-grid{grid-template-columns:1fr}
}
@media (max-width:480px){
  .vip-grid{grid-template-columns:1fr}
  .hero-stats b{font-size:1.3rem}
  .hero-stats li{padding:14px}
  .big-price{font-size:2.8rem}
  .brand-text small{letter-spacing:.12em}
}
@media (prefers-reduced-motion:reduce){*{transition:none!important;scroll-behavior:auto!important}}
.footer-intro{color:var(--blue-100);line-height:1.85;margin-bottom:.8em}
.footer-intro a{text-decoration:underline;text-underline-offset:3px}