/* Kieu dung chung cho chinh sach quyen rieng tu va trang ho tro cua ScreenMark.
   Cung cau truc voi legal.css cua Cutout Lab (song ngu bang cap lop tren <html>),
   doi sang mau tim cua ScreenMark (nen icon #6C48FF).
   Khong tai font ngoai, khong script ngoai: mot trang phap ly phai doc duoc ca khi
   mang xau, va khong nen tu no lai la mot nguon theo dau nguoi doc. */

:root {
  color-scheme: light dark;
  --bg: #fbfaff;
  --card: #ffffff;
  --ink: #1b1a23;
  --ink-soft: #5d5a6b;
  --line: #e7e4f3;
  --accent: #6c48ff;
  --accent-soft: #f2eeff;
  --accent-ink: #ffffff;
  --warn-bg: #fff8e6;
  --warn-line: #f0d79a;
}

@media (prefers-color-scheme: dark) {
  :root {
    --bg: #0f0e14;
    --card: #181721;
    --ink: #f1eff8;
    --ink-soft: #a29fb3;
    --line: #2b2938;
    --accent: #b3a0ff;
    --accent-soft: #1f1b33;
    --accent-ink: #14121f;
    --warn-bg: #241f14;
    --warn-line: #4d3f22;
  }
}

* { box-sizing: border-box; }

body {
  margin: 0;
  background: var(--bg);
  color: var(--ink);
  font: 16px/1.7 -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto,
        "Helvetica Neue", Arial, sans-serif;
  -webkit-text-size-adjust: 100%;
}

.wrap { max-width: 760px; margin: 0 auto; padding: 28px 20px 80px; }

header { border-bottom: 1px solid var(--line); padding-bottom: 20px; margin-bottom: 28px; }
h1 { font-size: 27px; line-height: 1.25; margin: 0 0 6px; letter-spacing: -0.02em; }
.sub { color: var(--ink-soft); font-size: 14px; margin: 0; }

h2 {
  font-size: 19px;
  margin: 40px 0 12px;
  padding-top: 4px;
  letter-spacing: -0.01em;
  scroll-margin-top: 16px;
}
h3 { font-size: 15px; margin: 24px 0 8px; }
p, li { color: var(--ink); }
p { margin: 0 0 14px; }
ul, ol { margin: 0 0 14px; padding-left: 22px; }
li { margin-bottom: 7px; }
a { color: var(--accent); text-decoration: underline; text-underline-offset: 2px; }
strong { font-weight: 650; }
code {
  font: 13px/1.5 ui-monospace, SFMono-Regular, Menlo, Consolas, monospace;
  background: var(--accent-soft);
  padding: 1px 5px;
  border-radius: 4px;
}

/* Khoi "noi ngay tu dau" — phan quan trong nhat cua trang, dat truoc muc luc. */
.lede {
  background: var(--card);
  border: 1px solid var(--line);
  border-left: 3px solid var(--accent);
  border-radius: 10px;
  padding: 18px 20px;
  margin: 0 0 12px;
}
.lede p:last-child { margin-bottom: 0; }

.note {
  background: var(--warn-bg);
  border: 1px solid var(--warn-line);
  border-radius: 10px;
  padding: 14px 18px;
  margin: 18px 0;
  font-size: 14.5px;
}
.note p:last-child { margin-bottom: 0; }

.toc { font-size: 14.5px; }
.toc ol { padding-left: 20px; }
.toc li { margin-bottom: 3px; }

/* Bang: phai cuon duoc theo chieu ngang tren dien thoai, khong lam ca trang cuon. */
.scroll { overflow-x: auto; margin: 0 0 18px; -webkit-overflow-scrolling: touch; }
table { border-collapse: collapse; width: 100%; min-width: 520px; font-size: 14px; }
th, td { text-align: left; padding: 10px 12px; border-bottom: 1px solid var(--line); vertical-align: top; }
th { font-weight: 650; color: var(--ink-soft); font-size: 12.5px; text-transform: uppercase; letter-spacing: 0.04em; }
tbody tr:last-child td { border-bottom: none; }

/* ---- Trang ho tro ---- */

.card {
  background: var(--card);
  border: 1px solid var(--line);
  border-radius: 12px;
  padding: 20px 22px;
  margin: 0 0 16px;
}
.card h2, .card h3 { margin-top: 0; }
.card p:last-child { margin-bottom: 0; }

.btn {
  display: inline-block;
  background: var(--accent);
  color: var(--accent-ink);
  text-decoration: none;
  font-weight: 650;
  padding: 11px 20px;
  border-radius: 999px;
}
.btn:hover { opacity: 0.92; }

.steps { counter-reset: step; list-style: none; padding-left: 0; }
.steps li {
  counter-increment: step;
  position: relative;
  padding-left: 40px;
  margin-bottom: 12px;
}
.steps li::before {
  content: counter(step);
  position: absolute;
  left: 0;
  top: 1px;
  width: 26px;
  height: 26px;
  border-radius: 50%;
  background: var(--accent-soft);
  border: 1px solid var(--line);
  color: var(--accent);
  font-weight: 650;
  font-size: 13px;
  line-height: 24px;
  text-align: center;
}

details {
  border: 1px solid var(--line);
  border-radius: 10px;
  background: var(--card);
  margin: 0 0 10px;
}
details[open] { border-color: var(--accent); }
summary {
  cursor: pointer;
  padding: 13px 16px;
  font-weight: 600;
  list-style: none;
}
summary::-webkit-details-marker { display: none; }
summary::after { content: "+"; float: right; color: var(--accent); font-weight: 700; }
details[open] summary::after { content: "\2212"; }
details .answer { padding: 0 16px 6px; }
details .answer p:last-child, details .answer ul:last-child { margin-bottom: 10px; }

footer {
  margin-top: 52px;
  padding-top: 20px;
  border-top: 1px solid var(--line);
  color: var(--ink-soft);
  font-size: 13.5px;
}

.pagenav { font-size: 14px; margin: 0 0 18px; color: var(--ink-soft); }
.pagenav a { margin-right: 14px; }

/* Chuyen ngon ngu. Khong co JavaScript thi chi hien tieng Viet — van la mot van ban
   day du, tot hon la an mat mot nua. */
[data-lang="en"] { display: none; }
html.lang-en [data-lang="vi"] { display: none; }
html.lang-en [data-lang="en"] { display: block; }

.langbar { display: flex; gap: 8px; margin-bottom: 18px; }
.langbar button {
  font: inherit;
  font-size: 13px;
  padding: 6px 14px;
  border-radius: 20px;
  border: 1px solid var(--line);
  background: var(--card);
  color: var(--ink-soft);
  cursor: pointer;
}
.langbar button[aria-pressed="true"] {
  background: var(--accent);
  border-color: var(--accent);
  color: var(--accent-ink);
  font-weight: 600;
}

@media print {
  .langbar, .pagenav { display: none; }
  [data-lang="en"], html.lang-en [data-lang="vi"] { display: block; }
  body { background: #fff; color: #000; }
  details { border: none; }
  details > :not(summary) { display: block; }
}