:root { --navy:#0c2240; --blue:#2b579a; --gold:#ffc446; --ink:#1d2733; --muted:#5b6876; --line:#dfe5ec; --soft:#f4f7fb; }
* { box-sizing: border-box; }
body { margin: 0; font-family: "Segoe UI", system-ui, Arial, sans-serif; color: var(--ink); line-height: 1.6; font-size: 15px; background: #fff; }
.cover { background: linear-gradient(160deg, var(--navy), #184a78); color: #fff; padding: 90px 60px 70px; }
.cover h1 { font-size: 46px; margin: 0 0 6px; }
.cover .sub { font-size: 22px; color: var(--gold); margin: 0 0 30px; }
.cover .meta { color: #c9d8ea; font-size: 15px; }
.cover img { width: 100%; max-width: 820px; border-radius: 10px; margin-top: 34px; box-shadow: 0 20px 50px rgba(0,0,0,.4); }
main { max-width: 980px; margin: 0 auto; padding: 30px 40px 60px; }
nav.toc { background: var(--soft); border: 1px solid var(--line); border-radius: 10px; padding: 18px 28px; margin: 20px 0 40px; }
nav.toc h2 { margin-top: 0; border: none; }
nav.toc ol { columns: 2; column-gap: 40px; margin: 0; padding-left: 20px; }
nav.toc li { margin: 3px 0; break-inside: avoid; }
nav.toc a { color: var(--blue); text-decoration: none; }
h2 { font-size: 26px; color: var(--navy); border-bottom: 3px solid var(--gold); padding-bottom: 6px; margin: 46px 0 16px; }
h3 { font-size: 19px; color: var(--blue); margin: 26px 0 8px; }
h4 { font-size: 16px; margin: 18px 0 6px; }
p { margin: 8px 0; }
figure { margin: 18px 0 22px; text-align: center; break-inside: avoid; }
figure img { max-width: 100%; border: 1px solid var(--line); border-radius: 6px; box-shadow: 0 6px 18px rgba(12,34,64,.12); }
figure.small img { max-width: 560px; }
figcaption { font-size: 13px; color: var(--muted); margin-top: 6px; }
table { border-collapse: collapse; width: 100%; margin: 12px 0 18px; font-size: 14px; break-inside: avoid; }
th, td { border: 1px solid var(--line); padding: 7px 10px; text-align: left; vertical-align: top; }
th { background: var(--soft); color: var(--navy); }
.tip, .note, .warn { border-radius: 8px; padding: 10px 14px; margin: 14px 0; break-inside: avoid; }
.tip { background: #eaf6ee; border-left: 4px solid #2e7d32; }
.note { background: #eaf1fb; border-left: 4px solid var(--blue); }
.warn { background: #fff4e0; border-left: 4px solid #ef6c00; }
.tip b:first-child, .note b:first-child, .warn b:first-child { display: inline-block; margin-right: 4px; }
kbd { background: #f1f3f6; border: 1px solid #c8ced6; border-bottom-width: 2px; border-radius: 4px; padding: 0 5px; font-family: Consolas, monospace; font-size: 13px; }
code { background: #f1f3f6; padding: 1px 5px; border-radius: 4px; font-family: Consolas, monospace; font-size: 13px; }
pre { background: #f6f8fa; border: 1px solid var(--line); border-radius: 6px; padding: 10px 14px; overflow-x: auto; font-size: 13px; break-inside: avoid; }
ol.steps li, ul li { margin: 4px 0; }
.ui { font-weight: 600; color: var(--navy); }
footer { text-align: center; color: var(--muted); font-size: 13px; border-top: 1px solid var(--line); padding: 20px; }
@media print {
  body { font-size: 11pt; }
  .cover { padding: 60px 40px; page-break-after: always; -webkit-print-color-adjust: exact; print-color-adjust: exact; }
  main { padding: 0 10px; max-width: none; }
  h2 { page-break-before: always; margin-top: 0; }
  nav.toc { page-break-after: always; }
  h2, h3, h4 { break-after: avoid; page-break-after: avoid; }
  figure img { max-height: 230mm; }
  .tip, .note, .warn, th { -webkit-print-color-adjust: exact; print-color-adjust: exact; }
  a { color: inherit; text-decoration: none; }
}
@page { size: A4; margin: 16mm 14mm; }