*{box-sizing:border-box}
body{margin:0;font:16px/1.7 system-ui,sans-serif;background:#111;color:#e6e6ea}
a{color:#a28cff}
header,footer{background:#1c1c22;padding:10px 16px;display:flex;flex-wrap:wrap;gap:12px;align-items:center;justify-content:space-between}
header .brand{font-weight:700;color:#fff;text-decoration:none;font-size:18px}
nav a,footer a{margin-right:12px;text-decoration:none}
footer{font-size:13px;color:#999;margin-top:30px}
main{max-width:780px;margin:0 auto;padding:18px 16px}
h1{font-size:28px;line-height:1.25;margin:10px 0 14px}
h2{font-size:21px;margin:28px 0 8px;color:#fff}
h3{font-size:17px;margin:18px 0 6px}
table{border-collapse:collapse;width:100%;margin:10px 0;font-size:14px}
th,td{border:1px solid #333;padding:7px 9px;text-align:left}
th{background:#22222a}
code{background:#22222a;padding:1px 6px;border-radius:4px}
.btn{display:inline-block;background:#6d4aff;color:#fff;padding:10px 18px;border-radius:8px;text-decoration:none;margin:8px 0}
.note{background:#1c1c22;border-left:4px solid #6d4aff;padding:10px 14px;margin:14px 0}
/* sidebar */
#sb{position:fixed;top:0;left:0;bottom:0;width:230px;background:#16161a;border-right:1px solid #2a2a33;padding:14px 10px;overflow:auto;z-index:20;transform:translateX(-100%);transition:transform .2s}
#sb.open{transform:none}
#sb a{display:block;padding:9px 12px;border-radius:8px;color:#d6d6de;text-decoration:none;margin:2px 0;font-size:15px}
#sb a:hover,#sb a.cur{background:#6d4aff;color:#fff}
#sb h4{margin:14px 12px 4px;font-size:12px;letter-spacing:.06em;color:#8a8a96;text-transform:uppercase}
#sbt{position:fixed;top:8px;left:8px;z-index:21;background:#6d4aff;color:#fff;border:0;border-radius:8px;padding:8px 12px;font-size:18px}
@media(max-width:899px){body.hs header{padding-left:56px}}
@media(min-width:900px){#sb{transform:none}#sbt{display:none}body.hs{padding-left:230px}}
/* calculator */
.calc label{display:block;margin:10px 0 3px;font-size:14px;color:#aaa}
.calc input,.calc select{width:100%;padding:10px;background:#22222a;color:#eee;border:1px solid #444;border-radius:6px;font-size:16px}
.res{background:#1c1c22;border-left:4px solid #6d4aff;padding:10px 14px;margin:14px 0;font-size:17px}