/* ==========================================================================
   BI10 2026 — Design tokens
   Nap TRUOC style.css. Moi mau cua trang khai bao o day, khong hardcode noi khac.

   Design system da dong bo voi DESIGN-INSTRUCTION.md.
   ========================================================================== */

:root {
  /* --- Nen (navy) --- */
  --navy-deep:    #010a26;   /* nen homepage/header dac */
  --navy-mid:     #021140;   /* nen section/frame */
  --navy-dark:    #0c1018;
  --navy-shade-1: #021140;
  --navy-shade-2: #022873;
  --navy-shade-3: #0b1f3a;
  --royal:        #022873;   /* nen khoi; KHONG dung cho chu nho */
  --neutral-surface: #222b38;

  /* --- Chu --- */
  --text:         #ffffff;   /* mac dinh; AAA tren moi sac navy */
  --text-soft:    #dde7f2;
  --text-muted:   #dde7f2;   /* chu phu; dung opacity khi can giam do noi */
  --text-dark:    #0c1018;

  /* --- Diem nhan: dung lam NEN KHOI mang chu trang, khong lam mau chu ---
     Dung chinh chung lam chu tren navy chi hop chu lon/display. */
  --accent-blue:  #1167d8;   /* hanh dong chinh (dang ky) */
  --accent-red:   #e11d2e;   /* moc thoi gian / deadline */
  --accent-pink:  #d91e63;   /* nhan phu */
  --accent-ink:   #0b1f3a;
  --signature-gradient: linear-gradient(90deg, #e11d2e 0%, #0b1f3a 50%, #1167d8 100%);

  /* --- Lop dem cho chu tren anh (xem DESIGN-INSTRUCTION.md muc 1) --- */
  --scrim:        rgba(0, 0, 0, .5);
  --overlay-box:  rgba(1, 10, 38, .58);
  --header-solid: rgba(1, 10, 38, .88);

  /* --- Chu --- */
  --font-display: 'Orbitron', sans-serif;
  --font-body:    'Inter', sans-serif;
  --font-intro-display: 'Chakra Petch', sans-serif;
  --font-nav: 'Chakra Petch', sans-serif;
  --font-vietnamese-display: 'Chakra Petch', sans-serif;
  --font-subheading: 'Orbitron', sans-serif;

  /* --- Chieu cao header co dinh: dung cho scroll-margin-top cua moi anchor --- */
  --header-h:     70px;
}

/* Header co dinh che tieu de cua section vua nhay toi -> tru san.
   Bo ban 2025 xu ly bang JS ($('#header').outerHeight() - 21). */
[id] {
  scroll-margin-top: calc(var(--header-h) + 16px);
}

/* Nen trang gan nhu luon toi, nen mac dinh la chu trang tren navy.
   Ban 2025 de body dung mau cam cu nen moi khoi chu phai ghi lai color: white. */
body {
  background: var(--navy-deep);
  color: var(--text);
  font-family: var(--font-body);
}

h1,
h2,
h3,
h4,
h5,
h6 {
  font-family: var(--font-display);
}

/* Tat animation cho nguoi bat giam chuyen dong. Ban 2025 chua co.
   Giu bo cuc, chi bo chuyen dong (xem muc 6). */
@media (prefers-reduced-motion: reduce) {
  *,
  *::before,
  *::after {
    animation-duration: .01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: .01ms !important;
    scroll-behavior: auto !important;
  }

  /* AOS dat opacity:0 ban dau -> phai tra lai, khong thi noi dung bien mat */
  [data-aos] {
    opacity: 1 !important;
    transform: none !important;
  }
}