*{box-sizing:border-box}

html{scroll-behavior:smooth}

body{

  margin:0;

  font-family:Arial,Helvetica,sans-serif;

  background:#f6f8fc;

  color:#172033;

  line-height:1.75;

}

a{text-decoration:none;color:inherit}

.header{

  background:#fff;

  border-bottom:1px solid #e6ebf2;

  position:sticky;

  top:0;

  z-index:20;

}

.nav{

  max-width:1120px;

  margin:auto;

  padding:16px 22px;

  display:flex;

  justify-content:space-between;

  align-items:center;

  gap:20px;

}

.brand{

  font-weight:800;

  letter-spacing:.4px;

  font-size:17px;

}

.brand span{

  display:block;

  font-size:11px;

  color:#6b7280;

  font-weight:600;

  letter-spacing:1px;

}

.home-link{

  padding:9px 14px;

  border:1px solid #d9e0ea;

  border-radius:8px;

  font-size:14px;

  font-weight:700;

  background:#fff;

}

.hero{

  background:linear-gradient(135deg,#0d1b2a,#17395f);

  color:#fff;

  padding:70px 22px 62px;

}

.hero-inner{

  max-width:900px;

  margin:auto;

}

.badge{

  display:inline-block;

  background:rgba(255,255,255,.12);

  border:1px solid rgba(255,255,255,.2);

  padding:7px 12px;

  border-radius:999px;

  font-size:12px;

  font-weight:700;

  letter-spacing:.8px;

  margin-bottom:18px;

}

h1{

  font-size:44px;

  line-height:1.2;

  margin:0 0 18px;

}

.hero p{

  max-width:760px;

  margin:0;

  font-size:18px;

  color:#dce8f5;

}

.container{

  max-width:900px;

  margin:auto;

  padding:50px 22px 70px;

}

.article{

  background:#fff;

  border:1px solid #e5eaf1;

  border-radius:16px;

  padding:42px;

}

h2{

  font-size:29px;

  line-height:1.3;

  margin:42px 0 15px;

}

h2:first-child{margin-top:0}

h3{

  font-size:21px;

  margin:28px 0 10px;

}

p{margin:0 0 18px}

ul{

  padding-left:22px;

  margin:0 0 22px;

}

li{margin-bottom:9px}

.note{

  background:#f3f7fb;

  border-left:4px solid #245b8f;

  padding:18px 20px;

  border-radius:8px;

  margin:28px 0;

}

.table-wrap{

  overflow-x:auto;

  margin:26px 0;

}

table{

  width:100%;

  border-collapse:collapse;

  min-width:650px;

}

th,td{

  border:1px solid #e3e8ef;

  padding:14px;

  text-align:left;

  vertical-align:top;

}

th{

  background:#f3f6fa;

}

.cta{

  margin-top:40px;

  padding:28px;

  background:#102a43;

  color:#fff;

  border-radius:14px;

}

.cta h2{margin:0 0 10px;font-size:26px}

.cta p{color:#d8e4ef}

.btn{

  display:inline-block;

  margin-top:8px;

  background:#fff;

  color:#102a43;

  padding:11px 17px;

  border-radius:8px;

  font-weight:800;

}

.related{

  margin-top:42px;

}

.related-grid{

  display:grid;

  grid-template-columns:repeat(2,1fr);

  gap:14px;

}

.related a{

  display:block;

  background:#fff;

  border:1px solid #e1e7ef;

  padding:17px;

  border-radius:10px;

  font-weight:700;

}

.footer{

  background:#0e1726;

  color:#cbd5e1;

  padding:28px 22px;

  text-align:center;

  font-size:14px;

}

.footer a{color:#fff}

@media(max-width:700px){

  h1{font-size:32px}

  .hero{padding:52px 20px}

  .article{padding:26px 20px}

  h2{font-size:25px}

  .related-grid{grid-template-columns:1fr}

  .brand{font-size:14px}

  .home-link{font-size:12px;padding:8px 10px}

}

.table-of-contents{

  margin:24px 0;

  border:1px solid #e1e6ee;

  border-radius:12px;

  background:#f8fafc;

  overflow:hidden;

}



.toc-toggle{

  width:100%;

  border:0;

  background:#071b35;

  color:#fff;

  padding:16px 18px;

  font-size:16px;

  font-weight:700;

  display:flex;

  justify-content:space-between;

  align-items:center;

  cursor:pointer;

}



.toc-arrow{

  font-size:18px;

  line-height:1;

}



.toc-content{

  display:none;

  padding:14px 22px;

}



.table-of-contents.open .toc-content{

  display:block;

}



.toc-content ul{

  margin:0;

  padding-left:18px;

}



.toc-content li{

  margin:10px 0;

}



.toc-content a{

  color:#0d3b66;

  text-decoration:none;

  font-weight:600;

}



.toc-content a:hover{

  text-decoration:underline;

}



@media(max-width:600px){

  .toc-toggle{

    padding:15px;

  }



  .toc-content{

    padding:12px 18px;

  }

}

.author-box{

    margin:30px 0;

    padding:20px;

    border:1px solid #ddd;

    border-radius:10px;

    background:#f8f9fa;

}

.author-box strong{

    display:block;

    font-size:18px;

    margin-bottom:5px;

}

.author-box span{

    display:block;

    font-size:14px;

    margin-bottom:12px;

    color:#555;

}

.author-box p{

    margin:0;

    line-height:1.6;

}