*{box-sizing:border-box}

html{scroll-behavior:smooth}

body{

margin:0;

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

background:#f6f8fc;

color:#172033;

line-height:1.7;

}

a{text-decoration:none;color:#155eef}

.header{

background:#fff;

border-bottom:1px solid #e6eaf0;

position:sticky;

top:0;

z-index:20;

}

.nav{

max-width:1100px;

margin:auto;

padding:16px 22px;

display:flex;

justify-content:space-between;

align-items:center;

gap:20px;

}

.brand{

font-weight:800;

font-size:18px;

color:#172033;

}

.brand span{color:#155eef}

.back{

font-size:14px;

font-weight:600;

}

.hero{

background:linear-gradient(135deg,#102a63,#155eef);

color:#fff;

padding:70px 22px;

}

.hero-inner{

max-width:900px;

margin:auto;

}

.kicker{

font-size:12px;

font-weight:700;

letter-spacing:1.5px;

opacity:.8;

margin-bottom:12px;

}

h1{

font-size:42px;

line-height:1.15;

margin:0 0 18px;

}

.hero p{

font-size:18px;

max-width:760px;

margin:0;

opacity:.94;

}

.notice{

max-width:900px;

margin:28px auto;

padding:16px 20px;

background:#fff7e6;

border:1px solid #ffe1a3;

border-radius:10px;

font-size:14px;

color:#6b4b00;

}

.content{

max-width:900px;

margin:0 auto;

padding:25px 22px 70px;

}

.article{

background:#fff;

border:1px solid #e7ebf2;

border-radius:16px;

padding:38px;

box-shadow:0 10px 30px rgba(15,23,42,.05);

}

h2{

font-size:28px;

line-height:1.25;

margin:42px 0 14px;

color:#172033;

}

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

h3{

font-size:20px;

margin:28px 0 10px;

}

p{margin:0 0 18px}

ul{

padding-left:22px;

margin-bottom:22px;

}

li{margin-bottom:9px}

.info-box{

background:#f3f7ff;

border-left:4px solid #155eef;

padding:18px;

border-radius:8px;

margin:25px 0;

}

.example{

background:#f8fafc;

border:1px solid #e5eaf1;

padding:22px;

border-radius:12px;

margin:24px 0;

}

.grid{

display:grid;

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

gap:18px;

margin:24px 0;

}

.card{

border:1px solid #e5eaf1;

padding:20px;

border-radius:12px;

background:#fff;

}

.card h3{margin-top:0}

.cta{

margin-top:45px;

padding:30px;

border-radius:14px;

background:#102a63;

color:#fff;

text-align:center;

}

.cta h2{

color:#fff;

margin:0 0 12px;

}

.button{

display:inline-block;

margin-top:10px;

padding:13px 22px;

border-radius:8px;

background:#fff;

color:#155eef;

font-weight:700;

}

.footer{

border-top:1px solid #e5eaf1;

background:#fff;

padding:30px 22px;

text-align:center;

font-size:13px;

color:#667085;

}

@media(max-width:700px){

h1{font-size:32px}

.article{padding:24px}

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

.hero{padding:55px 22px}

}

.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;

}