/* Trang văn bản (chính sách, điều khoản, xoá tài khoản): cùng token màu và chữ với index.html. */
:root {
  --bg: #ffffff; --surface: #f6f5f2; --line: #e4e2dd;
  --text: #15161a; --muted: #5f636b; --accent: #2F7FE3; --accent-soft: #e8f1fc;
}
@media (prefers-color-scheme: dark) {
  :root:not([data-theme="light"]) {
    --bg: #0f1012; --surface: #17181c; --line: #26282e;
    --text: #f2f2ef; --muted: #9b9ea7; --accent: #5AA2F0; --accent-soft: #10243a;
  }
}
:root[data-theme="dark"] {
  --bg: #0f1012; --surface: #17181c; --line: #26282e;
  --text: #f2f2ef; --muted: #9b9ea7; --accent: #5AA2F0; --accent-soft: #10243a;
}
* { box-sizing: border-box; }
html { -webkit-text-size-adjust: 100%; }
body {
  margin: 0; background: var(--bg); color: var(--text);
  font: 400 16px/1.65 "Be Vietnam Pro", system-ui, -apple-system, "Segoe UI", Roboto, sans-serif;
}
a { color: var(--accent); }
.wrap { max-width: 760px; margin: 0 auto; padding-inline: 16px; }
@media (min-width: 640px) { .wrap { padding-inline: 24px; } }
[data-lang="en"] .vi, [data-lang="vi"] .en { display: none !important; }

header { position: sticky; top: 0; z-index: 10; background: color-mix(in srgb, var(--bg) 88%, transparent); backdrop-filter: blur(12px); border-bottom: 1px solid var(--line); }
header .wrap { display: flex; align-items: center; gap: 16px; height: 60px; max-width: 1120px; }
.brand { display: flex; align-items: center; gap: 10px; font-weight: 700; font-size: 20px; text-decoration: none; color: var(--text); }
.brand img { width: 30px; height: 30px; display: block; }
nav { margin-left: auto; display: flex; align-items: center; gap: 4px; }
nav a { color: var(--muted); text-decoration: none; font-weight: 500; font-size: 15px; padding: 8px 12px; border-radius: 8px; }
nav a:hover { color: var(--text); background: var(--surface); }
.lang { margin-left: 8px; border: 1px solid var(--line); background: transparent; color: var(--text); border-radius: 999px; padding: 6px 12px; font: 600 13px "Be Vietnam Pro", system-ui, sans-serif; cursor: pointer; }
.lang:hover { background: var(--surface); }
.lang:focus-visible { outline: 2px solid var(--accent); outline-offset: 2px; }
@media (max-width: 600px) { nav a { display: none; } }

main { padding-block: 40px 64px; }
h1 { font-size: clamp(28px, 4.5vw, 38px); font-weight: 700; line-height: 1.15; letter-spacing: -.015em; margin: 0 0 8px; }
.meta { color: var(--muted); font-size: 14px; margin: 0 0 28px; }
h2 { font-size: 20px; font-weight: 600; line-height: 1.3; margin: 32px 0 10px; }
h3 { font-size: 16px; font-weight: 600; margin: 20px 0 6px; }
p { margin: 0 0 12px; }
ul, ol { margin: 0 0 12px; padding-left: 22px; }
li { margin-bottom: 6px; }
table { border-collapse: collapse; width: 100%; font-size: 15px; margin: 0 0 16px; }
th, td { text-align: left; vertical-align: top; padding: 8px 10px 8px 0; border-top: 1px solid var(--line); }
th { font-weight: 600; }
thead th { border-top: 0; color: var(--muted); font-weight: 600; font-size: 13px; }
.note { background: var(--surface); border: 1px solid var(--line); border-radius: 12px; padding: 14px 16px; margin: 0 0 16px; font-size: 15px; }
.steps li { margin-bottom: 10px; }
kbd { font: 600 14px "Be Vietnam Pro", system-ui, sans-serif; background: var(--surface); border: 1px solid var(--line); border-radius: 6px; padding: 1px 6px; }

footer { border-top: 1px solid var(--line); padding-block: 28px; color: var(--muted); font-size: 14px; }
footer .wrap { display: flex; flex-wrap: wrap; gap: 8px 24px; max-width: 1120px; }
footer a { color: var(--muted); text-decoration: none; }
footer a:hover { color: var(--text); text-decoration: underline; }