/* ============================================================
   TG号在线购买渠道 — Telegram 蓝主题
   系统字体栈 · 零外部请求 · 纯 CSS/SVG 视觉
   ============================================================ */

:root{
  --bg: #0e1621;
  --bg-2: #121d2a;
  --surface: #17212b;
  --surface-2: #1c2733;
  --line: rgba(255,255,255,.08);
  --line-2: rgba(255,255,255,.14);
  --primary: #2aabee;
  --primary-2: #22a7e0;
  --accent: #5ec4f7;
  --grad: linear-gradient(135deg,#2aabee 0%,#4fc3f7 100%);
  --text: #eef3f7;
  --dim: #93a4b3;
  --dim-2: #6b7d8d;
  --green: #7bd88f;
  --radius: 18px;
  --radius-sm: 12px;
  --shadow: 0 20px 50px -20px rgba(0,0,0,.6);
  --font: -apple-system,BlinkMacSystemFont,"PingFang SC","Microsoft YaHei","Segoe UI",Roboto,Helvetica,Arial,sans-serif;
}

*{margin:0;padding:0;box-sizing:border-box}
html{scroll-behavior:smooth}
body{
  font-family:var(--font);
  background:var(--bg);
  color:var(--text);
  line-height:1.7;
  -webkit-font-smoothing:antialiased;
  overflow-x:hidden;
}
a{color:inherit;text-decoration:none}
.ic{width:1em;height:1em;display:inline-block;vertical-align:-.12em;fill:none}
svg.ic{flex:none}

/* ---------- 按钮 ---------- */
.btn{
  display:inline-flex;align-items:center;gap:.5em;justify-content:center;
  font-weight:600;border-radius:999px;cursor:pointer;
  transition:transform .18s ease,box-shadow .18s ease,background .18s ease;
  white-space:nowrap;
}
.btn .ic{width:1.05em;height:1.05em}
.btn-primary{background:var(--grad);color:#03222f;box-shadow:0 8px 24px -8px rgba(42,171,238,.55)}
.btn-primary:hover{transform:translateY(-2px);box-shadow:0 14px 30px -8px rgba(42,171,238,.65)}
.btn-ghost{background:transparent;color:var(--text);border:1px solid var(--line-2)}
.btn-ghost:hover{background:var(--surface);border-color:var(--primary)}
.btn-light{background:#fff;color:#0a3a52}
.btn-light:hover{transform:translateY(-2px);box-shadow:0 14px 30px -10px rgba(255,255,255,.35)}
.btn-sm{padding:.5em 1.15em;font-size:.9rem}
.btn-lg{padding:.78em 1.7em;font-size:1.05rem}
.btn-block{width:100%}

/* ---------- 头部 ---------- */
.site-header{
  position:sticky;top:0;z-index:50;
  background:rgba(14,22,33,.8);backdrop-filter:blur(12px);
  border-bottom:1px solid var(--line);
}
.header-inner{
  max-width:1140px;margin:0 auto;padding:0 24px;height:68px;
  display:flex;align-items:center;justify-content:space-between;gap:20px;
}
.brand{display:flex;align-items:center;gap:10px;font-size:1.1rem;font-weight:700;color:var(--text)}
.brand-logo{
  width:38px;height:38px;border-radius:12px;background:var(--grad);
  display:flex;align-items:center;justify-content:center;color:#03222f;font-size:1.35rem;
  box-shadow:0 6px 16px -6px rgba(42,171,238,.6);
}
.brand-text b{color:var(--accent)}
.main-nav{display:flex;gap:26px}
.main-nav a{font-size:.95rem;color:var(--dim);transition:color .18s;position:relative}
.main-nav a:hover{color:var(--text)}
.main-nav a::after{content:"";position:absolute;left:0;bottom:-6px;width:0;height:2px;background:var(--grad);transition:width .22s}
.main-nav a:hover::after{width:100%}
.header-actions{display:flex;align-items:center;gap:12px}
.menu-toggle{display:none;background:none;border:none;cursor:pointer;padding:8px;flex-direction:column;gap:5px}
.menu-toggle span{display:block;width:22px;height:2px;background:var(--text);border-radius:2px;transition:.25s}

/* ---------- Hero ---------- */
.hero{position:relative;overflow:hidden;padding:88px 0 96px}
.hero-inner{
  max-width:1140px;margin:0 auto;padding:0 24px;
  display:grid;grid-template-columns:1.05fr .95fr;gap:56px;align-items:center;position:relative;z-index:2;
}
.hero-bg{
  position:absolute;inset:0;z-index:0;
  background:
    radial-gradient(600px 400px at 12% -8%,rgba(42,171,238,.22),transparent 60%),
    radial-gradient(500px 420px at 92% 20%,rgba(79,195,247,.16),transparent 60%);
}
.hero-bg::after{
  content:"";position:absolute;inset:0;
  background-image:linear-gradient(rgba(255,255,255,.03) 1px,transparent 1px),linear-gradient(90deg,rgba(255,255,255,.03) 1px,transparent 1px);
  background-size:44px 44px;
  mask-image:radial-gradient(ellipse at center,black 30%,transparent 75%);
}
.hero-badge{
  display:inline-flex;align-items:center;gap:.45em;
  background:rgba(42,171,238,.12);border:1px solid rgba(42,171,238,.3);
  color:var(--accent);padding:.35em .95em;border-radius:999px;font-size:.85rem;font-weight:600;
}
.hero-title{font-size:clamp(2rem,4.6vw,3.3rem);line-height:1.18;font-weight:800;margin:22px 0 18px;letter-spacing:-.5px}
.hero-title .grad{background:var(--grad);-webkit-background-clip:text;background-clip:text;-webkit-text-fill-color:transparent}
.hero-sub{color:var(--dim);font-size:1.08rem;max-width:34em;margin-bottom:30px}
.hero-cta{display:flex;gap:14px;flex-wrap:wrap;margin-bottom:40px}
.hero-stats{display:flex;gap:36px}
.stat b{display:block;font-size:1.05rem;color:var(--text);font-weight:700}
.stat span{font-size:.85rem;color:var(--dim)}

/* 聊天窗口 mockup */
.hero-visual{position:relative}
.chat-window{
  background:var(--surface);border:1px solid var(--line);border-radius:var(--radius);
  box-shadow:var(--shadow);overflow:hidden;max-width:420px;margin-left:auto;
}
.chat-head{display:flex;align-items:center;gap:6px;padding:12px 16px;background:var(--surface-2);border-bottom:1px solid var(--line)}
.chat-head .dot{width:10px;height:10px;border-radius:50%;background:#3b4a57}
.chat-head .dot:nth-child(1){background:#ff6b6b}.chat-head .dot:nth-child(2){background:#ffd166}.chat-head .dot:nth-child(3){background:#6ee7a0}
.chat-title{margin-left:10px;font-size:.85rem;color:var(--dim)}
.chat-body{padding:20px 16px;display:flex;flex-direction:column;gap:12px;min-height:300px}
.msg{max-width:78%;padding:10px 14px;border-radius:14px;font-size:.92rem;line-height:1.5}
.msg-in{background:var(--surface-2);border:1px solid var(--line);align-self:flex-start;border-bottom-left-radius:4px}
.msg-out{background:var(--grad);color:#03222f;align-self:flex-end;border-bottom-right-radius:4px}
.msg-typing{display:flex;gap:5px;align-items:center;padding:14px 16px}
.msg-typing span{width:7px;height:7px;border-radius:50%;background:#03222f;animation:blink 1.2s infinite}
.msg-typing span:nth-child(2){animation-delay:.2s}.msg-typing span:nth-child(3){animation-delay:.4s}
@keyframes blink{0%,80%,100%{opacity:.3}40%{opacity:1}}
.chat-input{display:flex;justify-content:space-between;align-items:center;padding:12px 16px;border-top:1px solid var(--line);color:var(--dim-2);font-size:.9rem}
.chat-send{width:30px;height:30px;border-radius:50%;background:var(--grad);color:#03222f;display:flex;align-items:center;justify-content:center;font-size:1rem}
.float-chip{
  position:absolute;display:flex;align-items:center;gap:.5em;
  background:var(--surface);border:1px solid var(--line-2);border-radius:999px;
  padding:.55em 1.1em;font-size:.85rem;font-weight:600;box-shadow:var(--shadow);
}
.chip-a{top:18%;left:4%}.chip-b{bottom:16%;right:2%}
.float-chip .ic{color:var(--accent)}

/* ---------- 区块通用 ---------- */
.section{padding:84px 0}
.section-alt{background:var(--bg-2);border-top:1px solid var(--line);border-bottom:1px solid var(--line)}
.section-head{max-width:640px;margin:0 auto 52px;text-align:center}
.tag{
  display:inline-block;background:rgba(42,171,238,.12);color:var(--accent);
  border:1px solid rgba(42,171,238,.28);padding:.3em .95em;border-radius:999px;
  font-size:.82rem;font-weight:600;margin-bottom:16px;
}
.section-head h2{font-size:clamp(1.6rem,3.4vw,2.3rem);font-weight:800;letter-spacing:-.3px}
.section-head p{color:var(--dim);margin-top:12px;font-size:1.02rem}
.section-head h2 + p{margin-top:12px}

/* ---------- Bento 优势 ---------- */
.bento{
  max-width:1140px;margin:0 auto;padding:0 24px;
  display:grid;grid-template-columns:repeat(3,1fr);gap:18px;
}
.bento-item{
  background:var(--surface);border:1px solid var(--line);border-radius:var(--radius);
  padding:28px;transition:transform .2s,border-color .2s;position:relative;overflow:hidden;
}
.bento-item:hover{transform:translateY(-4px);border-color:rgba(42,171,238,.45)}
.bento-lg{grid-column:span 1;grid-row:span 2;background:var(--grad);color:#03222f;border:none}
.bento-lg .bento-icon{background:rgba(3,34,47,.16);color:#03222f}
.bento-lg p{color:rgba(3,34,47,.85);font-size:1.02rem}
.bento-lg h3{font-size:1.5rem}
.bento-tag{display:inline-block;margin-top:16px;background:rgba(3,34,47,.14);padding:.3em .9em;border-radius:999px;font-size:.82rem;font-weight:700}
.bento-icon{
  width:48px;height:48px;border-radius:13px;background:rgba(42,171,238,.14);
  color:var(--accent);display:flex;align-items:center;justify-content:center;font-size:1.45rem;margin-bottom:16px;
}
.bento-item h3{font-size:1.15rem;margin-bottom:8px}
.bento-item p{color:var(--dim);font-size:.95rem}

/* ---------- 套餐 ---------- */
.packages{
  max-width:1140px;margin:0 auto;padding:0 24px;
  display:grid;grid-template-columns:repeat(3,1fr);gap:22px;
}
.pkg{
  background:var(--surface);border:1px solid var(--line);border-radius:var(--radius);
  padding:30px 26px;display:flex;flex-direction:column;position:relative;
  transition:transform .2s,border-color .2s;
}
.pkg:hover{transform:translateY(-5px);border-color:rgba(42,171,238,.4)}
.pkg-hot{border-color:rgba(42,171,238,.5);box-shadow:0 18px 44px -18px rgba(42,171,238,.4)}
.pkg-flag{
  position:absolute;top:-13px;right:22px;background:var(--grad);color:#03222f;
  font-size:.78rem;font-weight:700;padding:.25em .9em;border-radius:999px;
}
.pkg-head h3{font-size:1.3rem;margin-bottom:4px}
.pkg-head p{color:var(--dim);font-size:.9rem;margin-bottom:20px}
.pkg-list{list-style:none;margin-bottom:26px;flex:1}
.pkg-list li{display:flex;align-items:center;gap:10px;padding:9px 0;color:var(--text);font-size:.95rem;border-bottom:1px dashed var(--line)}
.pkg-list li:last-child{border-bottom:none}
.pkg-list .ic{color:var(--green);font-size:1.05rem}

/* ---------- 步骤 ---------- */
.steps{
  max-width:1140px;margin:0 auto;padding:0 24px;
  display:grid;grid-template-columns:repeat(4,1fr);gap:20px;
}
.step{
  background:var(--surface);border:1px solid var(--line);border-radius:var(--radius);
  padding:28px 24px;position:relative;
}
.step-num{
  font-size:2rem;font-weight:800;background:var(--grad);
  -webkit-background-clip:text;background-clip:text;-webkit-text-fill-color:transparent;
  display:block;margin-bottom:10px;
}
.step h3{font-size:1.1rem;margin-bottom:6px}
.step p{color:var(--dim);font-size:.92rem}

/* ---------- 服务保障 ---------- */
.guarantee{
  max-width:1140px;margin:0 auto;padding:0 24px;
  display:grid;grid-template-columns:1fr 1fr;gap:48px;align-items:center;
}
.guarantee-copy .tag{margin-bottom:16px}
.guarantee-copy h2{font-size:clamp(1.6rem,3.4vw,2.3rem);font-weight:800;margin-bottom:14px;letter-spacing:-.3px}
.guarantee-copy p{color:var(--dim);margin-bottom:26px}
.guarantee-grid{display:grid;grid-template-columns:1fr 1fr;gap:16px}
.g-item{
  display:flex;gap:14px;align-items:flex-start;background:var(--surface);
  border:1px solid var(--line);border-radius:var(--radius-sm);padding:20px;
}
.g-item .ic{font-size:1.5rem;color:var(--accent);margin-top:2px}
.g-item b{display:block;font-size:1rem}
.g-item span{color:var(--dim);font-size:.85rem}

/* ---------- 文章 ---------- */
.articles{
  max-width:1140px;margin:0 auto;padding:0 24px;
  display:grid;grid-template-columns:repeat(3,1fr);gap:22px;
}
.article{
  background:var(--surface);border:1px solid var(--line);border-radius:var(--radius);
  padding:28px;transition:transform .2s,border-color .2s;display:flex;flex-direction:column;
}
.article:hover{transform:translateY(-4px);border-color:rgba(42,171,238,.4)}
.article h3{font-size:1.12rem;line-height:1.45;margin-bottom:12px}
.article h3 a:hover{color:var(--accent)}
.article p{color:var(--dim);font-size:.92rem;margin-bottom:10px}
.article p:last-child{margin-bottom:0}

/* ---------- FAQ ---------- */
.faq{max-width:760px;margin:0 auto;padding:0 24px;display:flex;flex-direction:column;gap:14px}
.faq-item{background:var(--surface);border:1px solid var(--line);border-radius:var(--radius-sm);overflow:hidden}
.faq-q{
  width:100%;background:none;border:none;color:var(--text);cursor:pointer;
  display:flex;justify-content:space-between;align-items:center;gap:16px;
  padding:18px 22px;font-size:1.02rem;font-weight:600;text-align:left;font-family:var(--font);
}
.faq-mark{font-size:1.3rem;color:var(--accent);transition:transform .25s;flex:none}
.faq-item.open .faq-mark{transform:rotate(45deg)}
.faq-a{max-height:0;overflow:hidden;transition:max-height .3s ease}
.faq-a p{padding:0 22px 20px;color:var(--dim);font-size:.95rem}

/* ---------- CTA ---------- */
.cta{padding:0 24px 84px}
.cta-inner{
  max-width:1140px;margin:0 auto;border-radius:24px;
  background:var(--grad);color:#03222f;text-align:center;padding:64px 32px;
  position:relative;overflow:hidden;
}
.cta-inner::before{content:"";position:absolute;inset:0;background:radial-gradient(400px 200px at 80% 0%,rgba(255,255,255,.35),transparent 60%)}
.cta-inner h2{font-size:clamp(1.6rem,3.6vw,2.4rem);font-weight:800;position:relative}
.cta-inner p{color:rgba(3,34,47,.8);margin:12px 0 28px;position:relative;font-size:1.05rem}

/* ---------- 页脚 ---------- */
.site-footer{background:var(--bg-2);border-top:1px solid var(--line);padding:56px 24px 0}
.footer-inner{max-width:1140px;margin:0 auto;display:grid;grid-template-columns:1.4fr 1fr 1fr;gap:40px;padding-bottom:40px}
.footer-brand p{color:var(--dim);font-size:.92rem;margin-top:14px;max-width:26em}
.footer-col b{display:block;margin-bottom:16px;font-size:.95rem}
.footer-col a{display:block;color:var(--dim);font-size:.9rem;padding:5px 0;transition:color .18s}
.footer-col a:hover{color:var(--accent)}
.footer-bottom{border-top:1px solid var(--line);padding:20px 0;text-align:center;color:var(--dim-2);font-size:.85rem}

/* ---------- 滚动渐入（渐进增强，no-js 时内容始终可见） ---------- */
.reveal{opacity:0;transform:translateY(24px);transition:opacity .6s ease,transform .6s ease}
.reveal.revealed{opacity:1;transform:none}

/* ---------- 响应式 ---------- */
@media (max-width:960px){
  .hero-inner{grid-template-columns:1fr;gap:40px}
  .chat-window{margin:0 auto}
  .bento{grid-template-columns:1fr 1fr}
  .bento-lg{grid-column:span 2;grid-row:span 1}
  .packages{grid-template-columns:1fr}
  .steps{grid-template-columns:1fr 1fr}
  .guarantee{grid-template-columns:1fr}
  .articles{grid-template-columns:1fr}
  .footer-inner{grid-template-columns:1fr 1fr}
}
@media (max-width:640px){
  .main-nav{
    position:fixed;top:68px;left:0;right:0;background:var(--bg);
    flex-direction:column;gap:0;padding:8px 24px;border-bottom:1px solid var(--line);
    display:none;z-index:40;
  }
  .main-nav.open{display:flex}
  .main-nav a{padding:14px 0;border-bottom:1px solid var(--line)}
  .main-nav a:last-child{border-bottom:none}
  .main-nav a::after{display:none}
  .menu-toggle{display:flex}
  .header-actions .btn-sm{display:none}
  .bento{grid-template-columns:1fr}
  .bento-lg{grid-column:span 1}
  .steps{grid-template-columns:1fr}
  .guarantee-grid{grid-template-columns:1fr}
  .hero-stats{gap:22px}
  .footer-inner{grid-template-columns:1fr}
  .float-chip{display:none}
}