body {font-family: Arial, sans-serif; margin: 40px; line-height: 1.65;}
h1, h2, h3 {color: #1a1a1a;}
ul {margin-left: 20px;}
.toc a {text-decoration: none; color: #004080;}
.section {margin-top: 60px;}
img {max-width: 100%; height: auto; margin: 20px 0;}
hr {margin: 40px 0;}
table {border-collapse: collapse;}
table, th, td {border: 1px solid #999; padding: 8px;}