:root{--ink:#0B2545;--mut:#5A6B7F;--blue:#0165EF;--line:#DCE3EB;--bg:#F6F8FB}
*{box-sizing:border-box}
body{margin:0;font:17px/1.65 "Century Gothic",system-ui,sans-serif;color:var(--ink);background:var(--bg)}
main{max-width:860px;margin:0 auto;padding:20px 16px 60px}
a{color:var(--blue)}
h1{font-size:1.85rem;line-height:1.25;margin:10px 0 10px}
h2{font-size:1.2rem;margin:28px 0 8px}
.box h2{margin-top:0;font-size:1.05rem}
.lead{font-size:1.1rem}
.muted{color:var(--mut)}.small{font-size:.9rem}
.crumbs{font-size:.88rem;color:var(--mut);margin:18px 0 0}
nav.top{display:flex;align-items:center;gap:10px;flex-wrap:wrap}
nav.top .links{margin-left:auto;display:flex;gap:14px;font-size:.95rem;flex-wrap:wrap;align-items:center}
.brand{display:flex;align-items:center;gap:8px;text-decoration:none;color:inherit;font-weight:700;letter-spacing:.06em}
.brand .bt span{color:var(--blue)}
.navbtn{background:var(--blue);color:#fff!important;border-radius:999px;padding:4px 14px;text-decoration:none;font-weight:700}
.box{background:#fff;border:1px solid var(--line);border-radius:12px;padding:16px 20px;margin:18px 0}
.box p{margin:0}
.plain{border-left:5px solid var(--blue)}
.trap{border-left:5px solid #E0A100;background:#FFFBEF}
.keys{background:#EEF4FF;border-color:#CFE0FF}
.remember{font-size:1.08rem;background:#E8F7EE;border:1px solid #BFE5CC;border-radius:10px;padding:12px 18px}
.pq{background:#fff;border:1px solid var(--line);border-radius:12px;padding:16px 20px;margin:14px 0}
.pq .stem{margin:0 0 10px;font-weight:600}
.qn{display:inline-block;background:var(--ink);color:#fff;border-radius:6px;font-size:.78rem;padding:1px 8px;margin-right:6px;vertical-align:2px}
.pq ol{list-style:none;padding:0;margin:0 0 8px}
.pq li{margin:6px 0}
.pq li button{width:100%;text-align:left;font:inherit;color:inherit;background:#F9FBFD;border:1px solid #CBD5E1;border-radius:8px;padding:9px 12px;cursor:pointer}
.pq li button:hover:not([disabled]){border-color:var(--blue);background:#F2F7FF}
.pq li button[disabled]{cursor:default}
.pq li button b{color:var(--blue);margin-right:6px}
.pq li button.right{background:#E8F7EE;border-color:#2E9E5B}
.pq li button.wrong{background:#FDECEC;border-color:#C84B4B}
.pq summary{cursor:pointer;color:var(--blue);font-weight:600}
.pq details p{margin:8px 0 0}
.cta{background:#fff;border:1px solid #CFE0FF;border-radius:12px;padding:18px 22px;margin:30px 0}
.cta p{margin:6px 0 10px}
.btn{display:inline-block;background:var(--blue);color:#fff;border-radius:999px;padding:10px 22px;font-weight:700;text-decoration:none;margin:4px 6px 0 0}
.btn.ghost{background:#fff;color:var(--blue);border:1px solid var(--blue)}
ul.rel{padding-left:20px}ul.rel li{margin:6px 0}
.tw{overflow-x:auto}
table{border-collapse:collapse;width:100%;background:#fff;font-size:.95rem}
th,td{border:1px solid var(--line);padding:8px 10px;text-align:left;vertical-align:top}
th{background:#EEF4FF}
.grid{display:grid;grid-template-columns:repeat(auto-fill,minmax(250px,1fr));gap:14px;margin:20px 0}
.tcard{display:block;background:#fff;border:1px solid var(--line);border-radius:12px;padding:14px 16px;text-decoration:none;color:inherit}
.tcard:hover{border-color:var(--blue)}
.tcard strong{display:block;color:var(--blue);margin-bottom:4px}
.tcard span{font-size:.92rem;color:var(--mut)}
.tcard.hi{background:#EEF4FF;border-color:#CFE0FF}
footer{margin-top:40px;font-size:.85rem;color:var(--mut)}
@media (max-width:560px){h1{font-size:1.5rem}nav.top .links{margin-left:0;gap:10px}}