*{box-sizing:border-box}body{margin:0;font-family:system-ui,-apple-system,Segoe UI,Roboto,sans-serif;color:#1d2430;background:#f5f7fa;line-height:1.55}
header{background:#12161f;color:#fff;padding:18px 24px}header b{color:#ff5a36}main{max-width:960px;margin:0 auto;padding:24px}
section{background:#fff;border:1px solid #e3e7ee;border-radius:10px;padding:20px 24px;margin:18px 0}h1{margin:0;font-size:22px}h2{margin-top:0;font-size:19px}
.vi{color:#5b6576;font-size:14px}code{background:#eef1f6;padding:1px 5px;border-radius:4px}table{border-collapse:collapse;width:100%}td,th{border:1px solid #e3e7ee;padding:7px 9px;text-align:left;font-size:14px}th{background:#f0f3f8}
.flow{display:flex;flex-wrap:wrap;gap:8px;align-items:center}.flow div{background:#eef3ff;border:1px solid #c9d6f5;border-radius:8px;padding:8px 10px;font-size:14px}.flow span{color:#8a94a6}
.btn{display:inline-block;background:#ff5a36;color:#fff;padding:9px 16px;border-radius:7px;text-decoration:none;border:0;cursor:pointer;font-size:14px}.muted{color:#8a94a6;font-size:13px}
img{max-width:100%;border:1px solid #e3e7ee;border-radius:8px}footer{text-align:center;color:#8a94a6;font-size:13px;padding:24px}
.pin{background:#fff4e5;border:1px solid #ffc78a;border-radius:8px;padding:10px}.banner{background:#fff4e5;border:1px solid #ffc78a;padding:8px 12px;border-radius:8px;font-size:14px}
/* language toggle (v5) */
.lang-sw{position:fixed;top:10px;right:14px;z-index:99;background:#fff;border:1px solid #ddd;border-radius:6px;padding:3px 8px;font-size:13px;color:#999}
.lang-sw a{color:#666;text-decoration:none;padding:0 2px}.lang-sw a.on{color:#000;font-weight:700}
html[data-lang="vi"] .vi{display:none}