/* BIM route: technical blue, concrete white, signal orange and drawing-grid detail. */
body.book-bim {
  --ink: #1b2d3a;
  --muted: #667784;
  --line: #d5e0e5;
  --paper: #fbfdfe;
  --mist: #edf4f7;
  --brand: #1d6f91;
  --brand-strong: #124761;
  --brand-soft: #dceef4;
  --accent: #d96b3b;
  --accent-soft: #fbe5da;
  --blue: #386fb0;
  --blue-soft: #e1ebf8;
  --shadow: 0 18px 46px rgba(18, 71, 97, 0.14);
  --stage: #122b38;
  --stage-ink: #f4f8f8;
  --stage-muted: rgba(244, 248, 248, 0.72);
  --stage-line: rgba(244, 248, 248, 0.2);
  --stage-accent: #7bd0d1;
  --stage-acid: #c4dc9a;
  --stage-secondary: #e08051;
  --stage-surface: #fbfdfe;
  --stage-surface-strong: #e5f2f5;
  --stage-surface-line: #d5e0e5;
  background: #edf4f7;
}

body.book-bim::before {
  background: repeating-linear-gradient(90deg, rgba(29, 111, 145, 0.05) 0 1px, transparent 1px 56px),
    repeating-linear-gradient(0deg, rgba(217, 107, 59, 0.035) 0 1px, transparent 1px 56px);
  opacity: 0.76;
}

body.book-bim .brand-mark { color: #7bd0d1; border-color: #7bd0d1; box-shadow: 5px 5px 0 #d96b3b; }
body.book-bim .hero-band::before { content: "BIM / 25"; }
body.book-bim .hero-band::after { content: "模"; color: transparent; -webkit-text-stroke-color: rgba(123, 208, 209, 0.24); font-family: "Microsoft YaHei", sans-serif; }
body.book-bim .book-preview::after { content: "SOURCE / 10P"; }
body.book-bim .hero-band .primary-button,
body.book-bim .primary-button { box-shadow: 5px 5px 0 #d96b3b; }
body.book-bim .hero-band .primary-button:hover,
body.book-bim .primary-button:hover { box-shadow: 1px 1px 0 #d96b3b; }
body.book-bim .stat::before,
body.book-bim .course-item::before,
body.book-bim .practice-item::before,
body.book-bim .paper-card::before,
body.book-bim .progress-bar span,
body.book-bim .quiz-meter span { background: #d96b3b; }
body.book-bim .section:nth-of-type(odd) { background: rgba(255, 255, 255, 0.7); }

@media (max-width: 720px) { body.book-bim .hero-band::after { font-size: 180px; } }