/* public/css/chung.css — Thiết kế Bống Work theo BRAND_KIT */
@import url('https://fonts.googleapis.com/css2?family=Be+Vietnam+Pro:ital,wght@0,400;0,500;0,600;0,700;0,800;1,400;1,600&family=IBM+Plex+Mono:wght@400;500&display=swap');

:root {
  /* Brand colors */
  --navy-950: #04122f;
  --navy-900: #061a42; /* Tiêu đề */
  --navy-800: #082054; /* Màu chính · nền invert · nút primary */
  --navy-700: #0c2b6d;
  --navy-600: #123788;
  --navy-500: #1a4aa6;
  --teal-500: #00a9cc; /* Accent duy nhất · <= 5% */
  --teal-400: #33bad6;
  --teal-300: #7ed3e8;
  --teal-100: #e0f5fa;
  --teal-50: #f0fafd;
  --bg-page: #f7f8fb;
  --white: #ffffff;

  /* Neutrals & borders */
  --gray-100: #f1f3f7;
  --gray-200: #e2e6ee;
  --gray-300: #c9d0df;
  --gray-400: #9aa5bc;
  --gray-500: #6d7b97;
  --gray-600: #4a5670;
  --border-default: #e2e6ee;
  --border-subtle: #edf0f5;

  /* Semantics */
  --text-primary: #061a42;
  --text-secondary: #4a5670;
  --text-muted: #6d7b97;
  --text-on-navy: #ffffff;
  --success: #10b981;
  --warning: #f59e0b;
  --danger: #ef4444;

  /* Radii & Typography */
  --radius-control: 10px;
  --radius-card: 14px;
  --radius-bubble: 18px;
  --radius-pill: 999px;

  --font-sans: 'Be Vietnam Pro', -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
  --font-mono: 'IBM Plex Mono', monospace;

  --ease-standard: cubic-bezier(.2, .8, .26, 1);
  --shadow-sm: 0 1px 3px rgba(8, 32, 84, 0.05);
  --shadow-md: 0 4px 12px rgba(8, 32, 84, 0.08);
  --shadow-lg: 0 8px 24px rgba(8, 32, 84, 0.12);
}

*, *::before, *::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

html {
  font-size: 16px;
  scroll-behavior: smooth;
  -webkit-text-size-adjust: 100%;
}

body {
  font-family: var(--font-sans);
  background-color: var(--bg-page);
  color: var(--text-primary);
  line-height: 1.62;
  overflow-x: hidden;
  width: 100%;
  min-height: 100vh;
}

/* Typography tiếng Việt dấu chồng tầng */
h1, h2, h3, h4, h5, h6 {
  color: var(--navy-900);
  font-weight: 700;
  line-height: 1.25;
}

h1 { font-size: clamp(1.8rem, 4vw, 2.5rem); line-height: 1.2; }
h2 { font-size: clamp(1.4rem, 3vw, 2rem); line-height: 1.25; }
h3 { font-size: 1.25rem; line-height: 1.3; }
p { margin-bottom: 0.75rem; }
p:last-child { margin-bottom: 0; }

a {
  color: var(--navy-800);
  text-decoration: none;
  transition: color 150ms var(--ease-standard);
}
a:hover {
  color: var(--teal-500);
}

.mono {
  font-family: var(--font-mono);
  font-variant-numeric: tabular-nums;
}

.khung-chua {
  width: 100%;
  max-width: 1100px;
  margin-inline: auto;
  padding-inline: 16px;
}

@media (min-width: 768px) {
  .khung-chua {
    padding-inline: 24px;
  }
}

/* Section styling chung */
section {
  padding-block: 40px;
}

@media (min-width: 768px) {
  section {
    padding-block: 56px;
  }
}

.tieu-de-muc {
  margin-bottom: 20px;
  display: flex;
  align-items: baseline;
  justify-content: space-between;
  gap: 12px;
  flex-wrap: wrap;
}

.tieu-de-muc h2 {
  display: inline-flex;
  align-items: center;
  gap: 8px;
}

.tieu-de-muc .mo-ta {
  color: var(--text-muted);
  font-size: 0.9rem;
}

/* Khung trống cho các mục chưa dựng ở P1 */
.khung-trong {
  background: var(--white);
  border: 1px dashed var(--gray-300);
  border-radius: var(--radius-card);
  padding: 36px 20px;
  text-align: center;
  color: var(--text-muted);
  box-shadow: var(--shadow-sm);
}

.khung-trong .bieu-tuong {
  font-size: 2rem;
  margin-bottom: 8px;
  display: block;
  opacity: 0.7;
}

.khung-trong .thong-bao {
  font-size: 0.95rem;
  font-weight: 500;
  color: var(--text-secondary);
}

/* Card & Buttons */
.the {
  background: var(--white);
  border: 1px solid var(--border-default);
  border-radius: var(--radius-card);
  padding: 20px;
  box-shadow: var(--shadow-sm);
}

.nut-chinh {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 48px;
  padding: 0 24px;
  background-color: var(--navy-800);
  color: var(--text-on-navy);
  font-weight: 600;
  border-radius: var(--radius-pill);
  border: none;
  cursor: pointer;
  box-shadow: var(--shadow-sm);
  transition: transform 140ms var(--ease-standard), background-color 140ms var(--ease-standard);
  text-decoration: none;
}
.nut-chinh:hover {
  background-color: var(--navy-700);
  color: var(--text-on-navy);
  transform: translateY(-1px);
}
.nut-chinh:active {
  transform: translateY(0);
}

.nut-accent {
  background-color: var(--teal-500);
  color: var(--white);
}
.nut-accent:hover {
  background-color: var(--teal-400);
  color: var(--white);
}

.nut-phu {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 44px;
  padding: 0 18px;
  background-color: var(--white);
  color: var(--navy-900);
  font-weight: 500;
  border-radius: var(--radius-control);
  border: 1px solid var(--border-default);
  cursor: pointer;
}
.nut-phu:hover {
  background-color: var(--gray-100);
}

/* Reduced motion */
@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after {
    animation-duration: 0.001ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.001ms !important;
  }
}

/* Mục chưa có dữ liệu ẩn bằng thuộc tính hidden — không để CSS khác ghi đè. */
[hidden] { display: none !important; }