/* =============================================
   DayTinHoc.com - Education Blue & White
   Professional, Clean, Trustworthy, Modern
   ============================================= */

@import url("https://fonts.googleapis.com/css2?family=JetBrains+Mono:wght@400;500&family=Montserrat:wght@400;500;600;700;800;900&family=Inter:wght@300;400;500;600;700&display=swap");

:root {
  --bg-deep:      #f5f8ff;
  --bg-base:      #edf2ff;
  --bg-card:      #ffffff;
  --bg-card-2:    #f8faff;
  --bg-glass:     rgba(255, 255, 255, 0.9);
  --bg-header:    rgba(255, 255, 255, 0.95);
  --blue:         #1565C0;
  --blue-mid:     #1976D2;
  --blue-light:   #2196F3;
  --blue-pale:    #E3F2FD;
  --blue-glow:    rgba(21, 101, 192, 0.10);
  --blue-border:  rgba(21, 101, 192, 0.20);
  --accent:       #0288D1;
  --green:        #2E7D32;
  --orange:       #E65100;
  --amber:        #F59E0B;
  --violet:       #5C35B8;
  --violet-soft:  #7C5CE9;
  --text-dark:    #0D1B3E;
  --text-body:    #253461;
  --text-muted:   #6B7CA3;
  --text-light:   #9AAAC5;
  --text-white:   #0D1B3E;
  --border:       rgba(21, 101, 192, 0.14);
  --border-2:     rgba(21, 101, 192, 0.28);
  --border-light: #E0E8F8;
  --grad-blue:    linear-gradient(135deg, #1565C0 0%, #1976D2 100%);
  --grad-accent:  linear-gradient(135deg, #0288D1 0%, #1565C0 100%);
  --grad-card:    linear-gradient(145deg, rgba(21,101,192,0.04) 0%, rgba(255,255,255,0) 100%);
  --grad-zalo:    linear-gradient(135deg, #0068FF 0%, #00b4d8 100%);
  --font-display: 'Montserrat', sans-serif;
  --font-body:    'Inter', sans-serif;
  --font-code:    'JetBrains Mono', monospace;
  --section-pad: 80px;
  --container:   1200px;
  --radius:      12px;
  --radius-lg:   20px;
  --radius-xl:   28px;
  --shadow-sm:   0 2px 8px rgba(21, 101, 192, 0.08);
  --shadow-card: 0 4px 24px rgba(21, 101, 192, 0.10);
  --shadow-lg:   0 12px 48px rgba(21, 101, 192, 0.15);
  --transition:  0.3s cubic-bezier(0.4, 0, 0.2, 1);
}

*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }
html { scroll-behavior: smooth; font-size: 16px; }
body {
  font-family: var(--font-body);
  background: var(--bg-deep);
  color: var(--text-body);
  line-height: 1.7;
  overflow-x: hidden;
  position: relative;
}
body::before {
  content: '';
  position: fixed;
  inset: 0;
  background-image: radial-gradient(ellipse 80% 50% at 50% -20%, rgba(21,101,192,0.06) 0%, transparent 60%);
  pointer-events: none;
  z-index: 0;
}
.container {
  max-width: var(--container);
  margin: 0 auto;
  padding: 0 24px;
  position: relative;
  z-index: 1;
}
.section-pad { padding: var(--section-pad) 0; }
.gradient-text {
  background: var(--grad-blue);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}
.section-header { text-align: center; margin-bottom: 56px; }
.section-tag {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  font-family: var(--font-body);
  font-size: 12px;
  font-weight: 600;
  letter-spacing: 1.5px;
  text-transform: uppercase;
  color: var(--blue);
  background: var(--blue-pale);
  border: 1px solid var(--blue-border);
  padding: 6px 16px;
  border-radius: 100px;
  margin-bottom: 16px;
}
.section-title {
  font-family: var(--font-display);
  font-size: clamp(24px, 3vw, 38px);
  font-weight: 800;
  color: var(--text-dark);
  line-height: 1.2;
  margin-bottom: 12px;
}
.section-desc { font-size: 16px; color: var(--text-muted); max-width: 580px; margin: 0 auto; }

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  font-family: var(--font-display);
  font-size: 15px;
  font-weight: 700;
  padding: 14px 28px;
  border-radius: 10px;
  border: none;
  cursor: pointer;
  transition: var(--transition);
  white-space: nowrap;
  letter-spacing: 0.3px;
  text-decoration: none;
}
.btn-primary { background: var(--grad-blue); color: #fff; box-shadow: 0 4px 16px rgba(21,101,192,0.30); }
.btn-primary:hover { transform: translateY(-2px); box-shadow: 0 8px 28px rgba(21,101,192,0.45); }
.btn-zalo { background: var(--grad-zalo); color: #fff; box-shadow: 0 4px 16px rgba(0,104,255,0.25); }
.btn-zalo:hover { transform: translateY(-2px); box-shadow: 0 8px 24px rgba(0,104,255,0.40); }
.btn-full { width: 100%; }

.site-header {
  position: fixed;
  top: 0; left: 0; right: 0;
  z-index: 1000;
  background: var(--bg-header);
  backdrop-filter: blur(20px);
  -webkit-backdrop-filter: blur(20px);
  border-bottom: 1px solid var(--border-light);
  transition: var(--transition);
}
.site-header.scrolled { box-shadow: var(--shadow-card); border-bottom-color: var(--blue-border); }
.nav { display: flex; align-items: center; justify-content: space-between; height: 64px; }
.nav-logo {
  display: flex; align-items: center; gap: 10px;
  font-family: var(--font-display); font-size: 20px; font-weight: 900;
  color: var(--blue); text-decoration: none;
}
.logo-icon { font-size: 22px; display: none; }
.logo-dot { color: var(--accent); }
.nav-links { display: flex; align-items: center; gap: 4px; list-style: none; }
.nav-links li a {
  display: block; padding: 8px 16px;
  font-family: var(--font-display); font-size: 14px; font-weight: 600;
  color: var(--text-muted); border-radius: 8px; transition: var(--transition); text-decoration: none;
}
.nav-links li a:hover { color: var(--blue); background: var(--blue-pale); }
.btn-nav {
  background: var(--grad-blue) !important; color: #fff !important;
  padding: 8px 20px !important; font-weight: 700 !important;
  font-family: var(--font-display) !important; font-size: 14px !important;
  border-radius: 8px !important; border: none !important;
  box-shadow: 0 3px 10px rgba(21,101,192,0.25) !important;
}
.btn-nav:hover { transform: translateY(-1px) !important; box-shadow: 0 6px 16px rgba(21,101,192,0.35) !important; }
.nav-toggle { display: none; flex-direction: column; gap: 5px; background: none; border: none; cursor: pointer; padding: 8px; }
.nav-toggle span { display: block; width: 22px; height: 2px; background: var(--blue); border-radius: 2px; transition: var(--transition); }

.top-banner {
  padding-top: 64px;
  background: linear-gradient(135deg, #1565C0 0%, #1976D2 50%, #0288D1 100%);
  position: relative;
  overflow: hidden;
}
.top-banner::before {
  content: '';
  position: absolute; top: -80px; right: -80px;
  width: 400px; height: 400px;
  border-radius: 50%; background: rgba(255,255,255,0.06); pointer-events: none;
}
.top-banner::after {
  content: '';
  position: absolute; bottom: -60px; left: -60px;
  width: 300px; height: 300px;
  border-radius: 50%; background: rgba(255,255,255,0.04); pointer-events: none;
}
.banner-inner {
  display: flex; align-items: center; justify-content: space-between;
  gap: 40px; padding: 36px 0 40px;
}
.banner-text { flex: 1; }
.banner-label {
  font-family: var(--font-body); font-size: 11px;
  color: rgba(255,255,255,0.75); letter-spacing: 2px;
  text-transform: uppercase; margin-bottom: 12px;
  display: flex; align-items: center; gap: 10px;
}
.banner-label::before {
  content: ''; display: inline-block;
  width: 24px; height: 2px; background: rgba(255,255,255,0.6); border-radius: 2px;
}
.banner-title {
  font-family: var(--font-display); font-size: clamp(24px, 3vw, 38px);
  font-weight: 900; color: #ffffff; line-height: 1.2; margin-bottom: 10px;
}
.banner-title .gradient-text {
  background: linear-gradient(135deg, #BBDEFB 0%, #E3F2FD 100%);
  -webkit-background-clip: text; -webkit-text-fill-color: transparent; background-clip: text;
}
.banner-sub { font-size: 15px; color: rgba(255,255,255,0.80); font-weight: 400; }

.pricing-section { background: var(--bg-base); padding: 0 0 48px 0; }
.pricing-form-layout {
  display: grid; grid-template-columns: 1fr 1.25fr;
  gap: 28px; align-items: stretch; padding-top: 36px;
}
.pricing-card {
  height: 100%;
  background: var(--bg-card); border: 1px solid var(--border-light);
  border-radius: var(--radius-lg); padding: 32px;
  position: relative; overflow: hidden; box-shadow: var(--shadow-card); transition: var(--transition);
}
.pricing-card:hover { box-shadow: var(--shadow-lg); }
.pricing-card::before {
  content: ''; position: absolute; top: 0; left: 0; right: 0;
  height: 4px; background: var(--grad-blue); border-radius: var(--radius-lg) var(--radius-lg) 0 0;
}
.pricing-card::after {
  content: ''; position: absolute; top: -80px; right: -80px;
  width: 220px; height: 220px;
  background: radial-gradient(circle, rgba(21,101,192,0.05), transparent 70%); pointer-events: none;
}
.pricing-badge {
  display: inline-flex; align-items: center; gap: 6px;
  font-family: var(--font-body); font-size: 11px; font-weight: 700;
  letter-spacing: 1.5px; text-transform: uppercase;
  color: var(--blue); background: var(--blue-pale);
  border: 1px solid var(--blue-border); padding: 6px 14px;
  border-radius: 100px; margin-bottom: 24px;
}
.pricing-info-grid { display: flex; flex-direction: column; gap: 10px; margin-bottom: 24px; }
.pricing-info-item {
  display: flex; align-items: center; gap: 14px;
  padding: 13px 16px; background: var(--bg-deep);
  border: 1px solid var(--border-light); border-radius: 10px; transition: var(--transition);
}
.pricing-info-item:hover { background: var(--blue-pale); border-color: var(--blue-border); }
.pricing-info-icon { font-size: 18px; min-width: 28px; text-align: center; color: var(--blue); }
.pricing-info-item div { display: flex; flex-direction: column; gap: 1px; }
.pricing-info-label { font-family: var(--font-body); font-weight: 600; font-size: 11px; color: var(--text-muted); letter-spacing: 1px; text-transform: uppercase; }
.pricing-info-value { font-family: var(--font-display); font-size: 15px; color: var(--text-dark); font-weight: 700; }
.pricing-price-wrap { margin-bottom: 20px; }
.pricing-contact-note {
  font-family: var(--font-display); font-size: 13px; font-weight: 600; color: var(--blue);
  text-align: center; margin-bottom: 14px; padding: 12px 16px;
  background: var(--blue-pale); border: 1px solid var(--blue-border); border-radius: 10px;
}
.pricing-price-cta { display: flex; flex-direction: column; gap: 10px; }
.pricing-includes { border-top: 1px solid var(--border-light); padding-top: 20px; }
.pricing-includes-title {
  font-family: var(--font-body); font-size: 11px; font-weight: 600;
  letter-spacing: 2px; text-transform: uppercase; color: var(--text-muted); margin-bottom: 12px;
}
.pricing-includes ul { display: flex; flex-direction: column; gap: 8px; }
.pricing-includes li { font-size: 14px; color: var(--text-body); display: flex; align-items: center; gap: 8px; }

.form-card {
  height: 100%;
  background: var(--bg-card); border: 1px solid var(--border-light);
  border-radius: var(--radius-lg); padding: 36px;
  position: relative; overflow: hidden; box-shadow: var(--shadow-card); transition: var(--transition);
}
.form-card:hover { box-shadow: var(--shadow-lg); }
.form-card::before {
  content: ''; position: absolute; top: 0; left: 0; right: 0;
  height: 4px; background: var(--grad-accent); border-radius: var(--radius-lg) var(--radius-lg) 0 0;
}
.form-card::after {
  content: ''; position: absolute; bottom: -80px; right: -80px;
  width: 220px; height: 220px;
  background: radial-gradient(circle, rgba(2,136,209,0.06), transparent 70%); pointer-events: none;
}
.form-card-header { margin-bottom: 24px; padding-bottom: 18px; border-bottom: 1px solid var(--border-light); }
.form-card-header h3 {
  font-family: var(--font-display); font-size: 20px; font-weight: 800;
  color: var(--text-dark); margin-bottom: 6px; display: flex; align-items: center; gap: 10px;
}
.form-card-header p { font-size: 14px; color: var(--text-muted); line-height: 1.6; }
.form-card-header strong { color: var(--blue); font-weight: 700; }
.terminal-bar { display: none; }

.materials { background: var(--bg-card); border-top: 1px solid var(--border-light); }
.materials-grid { display: grid; grid-template-columns: repeat(2, 1fr); gap: 16px; }
.material-card {
  display: grid; grid-template-columns: 52px 1fr auto;
  align-items: center; gap: 16px;
  background: var(--bg-card); border: 1px solid var(--border-light);
  border-radius: var(--radius); padding: 18px 20px;
  text-decoration: none; color: inherit; transition: var(--transition);
  position: relative; overflow: hidden; box-shadow: var(--shadow-sm);
}
.material-card::before {
  content: ''; position: absolute; left: 0; top: 0; bottom: 0;
  width: 4px; border-radius: var(--radius) 0 0 var(--radius);
}
.material-card.excel-card::before { background: linear-gradient(180deg, #1565C0, #0288D1); }
.material-card.word-card::before  { background: linear-gradient(180deg, #5C35B8, #1565C0); }
.material-card.cert-card::before  { background: linear-gradient(180deg, #E65100, #F59E0B); }
.material-card:hover { transform: translateY(-3px); border-color: var(--blue-border); box-shadow: var(--shadow-lg); }
.material-icon-wrap {
  width: 52px; height: 52px; display: flex; align-items: center;
  justify-content: center; border-radius: 12px; font-size: 22px; flex-shrink: 0;
}
.excel-card .material-icon-wrap { background: var(--blue-pale); color: var(--blue); }
.word-card  .material-icon-wrap { background: rgba(92,53,184,0.10); color: var(--violet); }
.cert-card  .material-icon-wrap { background: rgba(230,81,0,0.10); color: var(--orange); }
.material-body { min-width: 0; }
.material-tag {
  font-family: var(--font-body); font-size: 10px; font-weight: 600;
  letter-spacing: 1.2px; text-transform: uppercase; display: block; margin-bottom: 3px;
}
.excel-card .material-tag { color: var(--blue); }
.word-card  .material-tag { color: var(--violet-soft); }
.cert-card  .material-tag { color: var(--orange); }
.material-body h4 {
  font-family: var(--font-display); font-size: 14px; font-weight: 700;
  color: var(--text-dark); margin-bottom: 2px; white-space: nowrap; overflow: hidden; text-overflow: ellipsis;
}
.material-body p { font-size: 12px; color: var(--text-muted); line-height: 1.4; }
.material-action { flex-shrink: 0; }
.download-btn {
  display: inline-flex; align-items: center; gap: 5px;
  font-family: var(--font-display); font-size: 12px; font-weight: 700;
  color: #fff; background: var(--grad-blue); border: none;
  padding: 7px 14px; border-radius: 8px; transition: var(--transition);
  white-space: nowrap; box-shadow: 0 2px 8px rgba(21,101,192,0.25);
}
.material-card:hover .download-btn { box-shadow: 0 4px 16px rgba(21,101,192,0.40); transform: translateY(-1px); }

.site-footer { background: var(--blue); }
.footer-bottom {
  display: flex; justify-content: space-between; align-items: center;
  padding: 22px 0; gap: 16px; flex-wrap: wrap;
}
.footer-bottom p { font-family: var(--font-body); font-size: 13px; color: rgba(255,255,255,0.75); }
.footer-bottom a { color: rgba(255,255,255,0.90); text-decoration: none; transition: var(--transition); font-weight: 600; }
.footer-bottom a:hover { color: #fff; text-decoration: underline; }

.back-to-top {
  position: fixed; bottom: 28px; right: 28px;
  width: 42px; height: 42px;
  background: var(--blue); border: 2px solid rgba(255,255,255,0.3);
  color: #fff; border-radius: 10px; font-size: 18px; font-weight: 700;
  cursor: pointer; opacity: 0; transform: translateY(12px);
  transition: var(--transition); box-shadow: 0 4px 16px rgba(21,101,192,0.30); z-index: 900;
}
.back-to-top.visible { opacity: 1; transform: translateY(0); }
.back-to-top:hover { background: var(--blue-light); box-shadow: 0 6px 20px rgba(21,101,192,0.45); }

.animate-up { opacity: 0; transform: translateY(30px); transition: opacity 0.7s ease, transform 0.7s ease; }
.animate-up.visible { opacity: 1; transform: translateY(0); }

.form-card label { color: var(--text-dark) !important; font-family: var(--font-body) !important; font-size: 13px !important; font-weight: 600 !important; margin-bottom: 6px; display: block; }
.form-card input, .form-card textarea {
  width: 100%; background: var(--bg-deep) !important;
  border: 1.5px solid var(--border-light) !important; border-radius: 10px !important;
  color: var(--text-dark) !important; font-family: var(--font-body) !important;
  padding: 12px 16px !important; font-size: 14px !important; transition: var(--transition) !important;
}
.form-card input:focus, .form-card textarea:focus {
  outline: none !important; border-color: var(--blue) !important;
  background: #fff !important; box-shadow: 0 0 0 3px rgba(21,101,192,0.12) !important;
}
.form-card button[type="submit"], .form-card .omni-submit-btn {
  background: var(--grad-blue) !important; color: #fff !important;
  border: none !important; padding: 14px 24px !important;
  border-radius: 10px !important; font-family: var(--font-display) !important;
  font-weight: 700 !important; font-size: 15px !important;
  cursor: pointer !important; width: 100% !important; margin-top: 10px !important;
  transition: var(--transition) !important; box-shadow: 0 4px 16px rgba(21,101,192,0.30) !important;
}
.form-card button[type="submit"]:hover, .form-card .omni-submit-btn:hover {
  transform: translateY(-2px) !important; box-shadow: 0 8px 28px rgba(21,101,192,0.45) !important;
}

::selection { background: var(--blue-pale); color: var(--blue); }

.floating-contact { position: fixed; bottom: 90px; right: 28px; display: flex; flex-direction: column; gap: 10px; z-index: 999; }
.f-btn {
  width: 42px; height: 42px; border-radius: 10px;
  display: flex; flex-direction: column; align-items: center; justify-content: center;
  text-decoration: none; color: #fff; font-family: var(--font-body); font-weight: 700; font-size: 9px;
  border: none; box-shadow: 0 4px 14px rgba(0,0,0,0.18); transition: all 0.3s ease;
}
.f-btn:hover { transform: scale(1.10); box-shadow: 0 6px 20px rgba(0,0,0,0.25); color: #fff; }
.f-btn i { font-size: 16px; margin-bottom: 0; }
.btn-call { background: #2E7D32; }
.btn-map { background: #E65100; }
.btn-zalo-f { background: #1565C0; }
.btn-facebook { background: #1877F2; }
.btn-call:hover { background: #388E3C; }
.btn-map:hover { background: #F4511E; }
.btn-zalo-f:hover { background: #1976D2; }
.btn-facebook:hover { background: #166FE5; }
.zalo-text { font-size: 12px; margin-bottom: 1px; line-height: 1; font-family: var(--font-display); font-weight: 800; }

@media (max-width: 900px) {
  .pricing-form-layout { grid-template-columns: 1fr; }
  .materials-grid { grid-template-columns: 1fr; }
  .banner-inner { flex-direction: column; align-items: flex-start; gap: 24px; padding: 28px 0 32px; }
}
@media (max-width: 768px) {
  .nav-links { display: none; }
  .nav-links.open {
    display: flex; flex-direction: column;
    position: absolute; top: 64px; left: 0; right: 0;
    background: var(--bg-header); border-bottom: 1px solid var(--border-light);
    padding: 12px 24px; gap: 4px; z-index: 999; box-shadow: var(--shadow-card);
  }
  .nav-toggle { display: flex; }
  .material-card { grid-template-columns: 44px 1fr; }
  .material-action { display: none; }
  .footer-bottom { flex-direction: column; text-align: center; gap: 10px; }
  .floating-contact { bottom: 80px; right: 16px; gap: 8px; }
  .f-btn { width: 42px; height: 42px; font-size: 8px; border-radius: 10px; }
  .f-btn i { font-size: 14px; }
  .zalo-text { font-size: 10px; }
}
@media (max-width: 480px) {
  .pricing-card, .form-card { padding: 24px 20px; }
  .banner-title { font-size: 22px; }
}