*{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 #e5e9f0;

    position:sticky;

    top:0;

    z-index:10;

}

.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:.3px;

}

.back{

    font-size:14px;

    color:#38506b;

    font-weight:600;

}



.hero{

    background:linear-gradient(135deg,#10243e,#1d4d72);

    color:#fff;

    padding:75px 22px 65px;

}

.hero-inner{

    max-width:900px;

    margin:auto;

}

.kicker{

    font-size:13px;

    letter-spacing:1.5px;

    font-weight:700;

    opacity:.8;

    margin-bottom:14px;

}

h1{

    font-size:clamp(34px,5vw,58px);

    line-height:1.12;

    margin:0 0 20px;

}

.hero p{

    max-width:760px;

    font-size:18px;

    opacity:.92;

}



.container{

    max-width:900px;

    margin:0 auto;

    padding:55px 22px;

}

article{

    background:#fff;

    padding:clamp(24px,5vw,55px);

    border-radius:18px;

    box-shadow:0 10px 35px rgba(20,40,70,.07);

}



h2{

    font-size:30px;

    line-height:1.25;

    margin-top:48px;

    color:#162b45;

}

h3{

    font-size:22px;

    margin-top:30px;

    color:#1b3655;

}

p{margin:16px 0}

ul{

    padding-left:22px;

}

li{margin:10px 0}



.highlight{

    background:#eef5fb;

    border-left:4px solid #2c6aa0;

    padding:20px;

    border-radius:10px;

    margin:28px 0;

}



.example{

    background:#f8fafc;

    border:1px solid #e3e9f0;

    padding:22px;

    border-radius:12px;

    margin:28px 0;

}



.related{

    margin-top:55px;

    padding-top:30px;

    border-top:1px solid #e5e9f0;

}

.related-grid{

    display:grid;

    grid-template-columns:repeat(auto-fit,minmax(200px,1fr));

    gap:14px;

}

.related a{

    display:block;

    background:#f4f7fa;

    padding:17px;

    border-radius:10px;

    font-weight:600;

    color:#214d74;

}



.disclaimer{

    margin-top:45px;

    background:#fff8e8;

    border:1px solid #f0dfad;

    padding:22px;

    border-radius:12px;

    font-size:14px;

    color:#5f532e;

}



.footer{

    text-align:center;

    padding:35px 20px;

    color:#667085;

    font-size:14px;

}



@media(max-width:600px){

    .nav{padding:14px 16px}

    .brand{font-size:14px}

    article{padding:24px 20px}

}

.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;

}