/* ============================================================
   BeHocBai — Base / Design Tokens
   Phong cách: playful, tươi sáng, bo tròn, thân thiện với bé
   ============================================================ */

@import url('https://fonts.googleapis.com/css2?family=Baloo+2:wght@400;500;600;700;800&family=Quicksand:wght@400;500;600;700&display=swap');

:root {
  /* --- Màu thương hiệu --- */
  --c-primary:    #3B82F6;   /* xanh dương (giữ theme-color cũ) */
  --c-primary-dk: #2563EB;
  --c-sun:        #FBBF24;   /* vàng nắng */
  --c-coral:      #FB7185;   /* hồng san hô */
  --c-mint:       #34D399;   /* xanh bạc hà */
  --c-grape:      #A78BFA;   /* tím nho */
  --c-orange:     #FB923C;

  /* --- Nền & chữ --- */
  --bg:        #FFF9F0;      /* kem ấm */
  --bg-card:   #FFFFFF;
  --ink:       #1F2937;      /* chữ chính */
  --ink-soft:  #6B7280;      /* chữ phụ */
  --line:      #FDE8C8;

  /* --- Hình khối --- */
  --r-sm: 12px;
  --r-md: 20px;
  --r-lg: 32px;
  --r-pill: 999px;

  /* --- Bóng đổ vui mắt --- */
  --sh-sm: 0 4px 0 rgba(0,0,0,.08);
  --sh-md: 0 8px 24px rgba(59,130,246,.12);
  --sh-lift: 0 12px 32px rgba(0,0,0,.12);

  /* --- Font --- */
  --f-display: 'Baloo 2', system-ui, sans-serif;
  --f-body: 'Quicksand', system-ui, sans-serif;

  --maxw: 1140px;
}

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

html { scroll-behavior: smooth; }

body {
  font-family: var(--f-body);
  color: var(--ink);
  background: var(--bg);
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
  overflow-x: hidden;
}

h1,h2,h3,h4 { font-family: var(--f-display); font-weight: 800; line-height: 1.15; }

a { color: inherit; text-decoration: none; }
img { max-width: 100%; display: block; }

.container { width: 100%; max-width: var(--maxw); margin: 0 auto; padding: 0 20px; }

/* --- Nút bấm --- */
.btn {
  font-family: var(--f-display);
  font-weight: 700;
  font-size: 1.05rem;
  border: none;
  border-radius: var(--r-pill);
  padding: 14px 30px;
  cursor: pointer;
  display: inline-flex;
  align-items: center;
  gap: 8px;
  transition: transform .15s ease, box-shadow .15s ease;
  text-align: center;
}
.btn:active { transform: translateY(2px); }

.btn-primary {
  background: var(--c-primary);
  color: #fff;
  box-shadow: 0 5px 0 var(--c-primary-dk);
}
.btn-primary:hover { transform: translateY(-2px); box-shadow: 0 7px 0 var(--c-primary-dk); }

.btn-sun {
  background: var(--c-sun);
  color: #7c4a03;
  box-shadow: 0 5px 0 #d99100;
}
.btn-sun:hover { transform: translateY(-2px); box-shadow: 0 7px 0 #d99100; }

/* --- Tiện ích --- */
.center { text-align: center; }
.sr-only { position:absolute; width:1px; height:1px; overflow:hidden; clip:rect(0,0,0,0); }

@media (prefers-reduced-motion: reduce) {
  * { animation: none !important; transition: none !important; }
}