/* ==========================================================================
   QUANG MINH TRÍ - UI COMPONENTS
   Buttons, Navigation, Cards, Forms, Footer
   ========================================================================== */

/* Buttons */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 0.6rem;
  padding: 0.85rem 1.75rem;
  border-radius: var(--radius-md);
  font-weight: 600;
  font-size: 0.975rem;
  line-height: 1;
  text-decoration: none;
  cursor: pointer;
  transition: all var(--transition-normal);
  border: 1px solid transparent;
  white-space: nowrap;
}

.btn:active {
  transform: translateY(1px);
}

.btn svg {
  width: 18px;
  height: 18px;
  transition: transform var(--transition-fast);
}

.btn:hover svg {
  transform: translateX(3px);
}

.btn-primary {
  background: linear-gradient(135deg, var(--color-electric-blue) 0%, var(--color-secondary-navy) 100%);
  color: var(--color-white);
  box-shadow: 0 4px 14px rgba(19, 119, 200, 0.35);
}

.btn-primary:hover {
  background: linear-gradient(135deg, #1066ae 0%, #05295e 100%);
  color: var(--color-white);
  box-shadow: 0 6px 20px rgba(19, 119, 200, 0.45);
  transform: translateY(-1px);
}

.btn-gold {
  background: linear-gradient(135deg, var(--color-light-gold) 0%, var(--color-primary-gold) 100%);
  color: var(--color-primary-navy);
  font-weight: 700;
  box-shadow: var(--shadow-gold);
}

.btn-gold:hover {
  background: linear-gradient(135deg, #fae8be 0%, #b88a40 100%);
  color: var(--color-primary-navy);
  box-shadow: 0 10px 28px rgba(197, 151, 77, 0.35);
  transform: translateY(-1px);
}

.btn-secondary {
  background-color: transparent;
  color: var(--color-primary-navy);
  border: 1.5px solid var(--color-primary-navy);
}

.btn-secondary:hover {
  background-color: var(--color-primary-navy);
  color: var(--color-white);
  transform: translateY(-1px);
}

.btn-secondary-light {
  background-color: rgba(255, 255, 255, 0.08);
  color: var(--color-white);
  border: 1.5px solid rgba(255, 255, 255, 0.25);
  backdrop-filter: blur(8px);
}

.btn-secondary-light:hover {
  background-color: var(--color-white);
  color: var(--color-primary-navy);
  border-color: var(--color-white);
  transform: translateY(-1px);
}

.btn-sm {
  padding: 0.6rem 1.2rem;
  font-size: 0.875rem;
  border-radius: var(--radius-sm);
}

.btn-lg {
  padding: 1.05rem 2.25rem;
  font-size: 1.05rem;
  border-radius: var(--radius-md);
}

/* Header & Navigation */
.site-header {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: var(--header-height);
  z-index: 1000;
  background-color: rgba(255, 255, 255, 0.88);
  backdrop-filter: blur(14px);
  -webkit-backdrop-filter: blur(14px);
  border-bottom: 1px solid rgba(226, 232, 240, 0.8);
  transition: all var(--transition-normal);
}

.site-header.scrolled {
  background-color: rgba(255, 255, 255, 0.96);
  box-shadow: 0 4px 20px rgba(5, 41, 94, 0.06);
  height: 72px;
}

.header-container {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 100%;
}

.brand-link {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  text-decoration: none;
}

.brand-link img {
  height: 44px;
  width: auto;
}

.nav-desktop {
  display: flex;
  align-items: center;
  gap: 1.8rem;
}

.nav-link {
  font-size: 0.95rem;
  font-weight: 600;
  color: var(--color-primary-navy);
  position: relative;
  padding: 0.5rem 0;
  transition: color var(--transition-fast);
}

.nav-link::after {
  content: '';
  position: absolute;
  bottom: 0;
  left: 0;
  width: 0;
  height: 2px;
  background-color: var(--color-electric-blue);
  transition: width var(--transition-normal);
}

.nav-link:hover {
  color: var(--color-electric-blue);
}

.nav-link:hover::after,
.nav-link.active::after {
  width: 100%;
}

.nav-cta {
  display: flex;
  align-items: center;
  gap: 1rem;
}

/* Mobile Menu Toggle */
.mobile-toggle {
  display: none;
  background: none;
  border: none;
  cursor: pointer;
  padding: 0.5rem;
  color: var(--color-primary-navy);
}

.mobile-toggle svg {
  width: 28px;
  height: 28px;
}

/* Mobile Drawer */
.mobile-drawer {
  position: fixed;
  top: 0;
  right: -100%;
  width: min(85vw, 360px);
  height: 100vh;
  background-color: var(--color-white);
  z-index: 1100;
  padding: 2rem 1.75rem;
  display: flex;
  flex-direction: column;
  box-shadow: -10px 0 30px rgba(5, 41, 94, 0.15);
  transition: right var(--transition-smooth);
}

.mobile-drawer.open {
  right: 0;
}

.drawer-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: 2.5rem;
  padding-bottom: 1rem;
  border-bottom: 1px solid var(--color-border);
}

.drawer-header img {
  height: 38px;
  width: auto;
}

.drawer-close {
  background: none;
  border: none;
  cursor: pointer;
  color: var(--color-primary-navy);
  padding: 0.4rem;
}

.mobile-nav-links {
  display: flex;
  flex-direction: column;
  gap: 1.25rem;
  margin-bottom: 2.5rem;
}

.mobile-nav-link {
  font-size: 1.15rem;
  font-weight: 700;
  color: var(--color-primary-navy);
  text-decoration: none;
  padding: 0.5rem 0;
  border-bottom: 1px solid rgba(226, 232, 240, 0.6);
}

.mobile-nav-link:hover,
.mobile-nav-link.active {
  color: var(--color-electric-blue);
}

.drawer-footer {
  margin-top: auto;
  display: flex;
  flex-direction: column;
  gap: 1rem;
}

.drawer-backdrop {
  position: fixed;
  inset: 0;
  background-color: rgba(5, 41, 94, 0.45);
  backdrop-filter: blur(4px);
  z-index: 1050;
  opacity: 0;
  pointer-events: none;
  transition: opacity var(--transition-normal);
}

.drawer-backdrop.active {
  opacity: 1;
  pointer-events: auto;
}

/* Card Styles */
.card {
  background-color: var(--color-white);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-lg);
  padding: 2rem;
  transition: transform var(--transition-normal), box-shadow var(--transition-normal), border-color var(--transition-normal);
  position: relative;
}

.card:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-lg);
  border-color: rgba(19, 119, 200, 0.3);
}

.card-dark {
  background-color: rgba(10, 37, 76, 0.75);
  border: 1px solid var(--color-dark-border);
  backdrop-filter: blur(10px);
}

.card-dark:hover {
  border-color: var(--color-light-blue);
  box-shadow: 0 16px 36px rgba(0, 0, 0, 0.35);
}

/* Badges */
.badge {
  display: inline-flex;
  align-items: center;
  gap: 0.4rem;
  padding: 0.3rem 0.75rem;
  font-size: 0.8rem;
  font-weight: 700;
  font-family: var(--font-mono);
  border-radius: var(--radius-sm);
  letter-spacing: 0.04em;
}

.badge-navy {
  background-color: rgba(5, 41, 94, 0.08);
  color: var(--color-primary-navy);
}

.badge-blue {
  background-color: rgba(19, 119, 200, 0.1);
  color: var(--color-electric-blue);
}

.badge-gold {
  background-color: rgba(197, 151, 77, 0.15);
  color: var(--color-dark-gold);
}

.badge-green {
  background-color: var(--color-success-bg);
  color: var(--color-success);
}

/* Form Styles */
.form-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 1.25rem;
}

.form-group {
  display: flex;
  flex-direction: column;
  gap: 0.45rem;
}

.form-group.col-full {
  grid-column: 1 / -1;
}

.form-label {
  font-size: 0.9rem;
  font-weight: 600;
  color: var(--color-primary-navy);
}

.section-dark .form-label {
  color: var(--color-white);
}

.form-label .required {
  color: var(--color-error);
}

.form-input,
.form-select,
.form-textarea {
  width: 100%;
  padding: 0.85rem 1rem;
  background-color: var(--color-white);
  border: 1.5px solid var(--color-border);
  border-radius: var(--radius-md);
  font-size: 0.95rem;
  color: var(--color-text-main);
  transition: border-color var(--transition-fast), box-shadow var(--transition-fast);
}

.section-dark .form-input,
.section-dark .form-select,
.section-dark .form-textarea {
  background-color: rgba(5, 41, 94, 0.6);
  border-color: rgba(141, 193, 223, 0.3);
  color: var(--color-white);
}

.form-input:focus,
.form-select:focus,
.form-textarea:focus {
  outline: none;
  border-color: var(--color-electric-blue);
  box-shadow: 0 0 0 3px rgba(19, 119, 200, 0.15);
}

.form-textarea {
  resize: vertical;
  min-height: 120px;
}

/* Anti-spam honeypot (invisible to humans) */
.sr-only-hp {
  position: absolute;
  width: 1px;
  height: 1px;
  padding: 0;
  margin: -1px;
  overflow: hidden;
  clip: rect(0, 0, 0, 0);
  white-space: nowrap;
  border-width: 0;
}

.form-feedback {
  padding: 1rem 1.25rem;
  border-radius: var(--radius-md);
  margin-top: 1rem;
  display: none;
  font-size: 0.925rem;
}

.form-feedback.success {
  display: block;
  background-color: var(--color-success-bg);
  border: 1px solid #A7F3D0;
  color: #065F46;
}

.form-feedback.error {
  display: block;
  background-color: var(--color-error-bg);
  border: 1px solid #FECACA;
  color: #991B1B;
}

/* Footer */
.site-footer {
  background: linear-gradient(180deg, #031836 0%, #020F24 100%);
  color: #94A3B8;
  border-top: 1px solid rgba(141, 193, 223, 0.15);
  padding-top: clamp(4rem, 6vw, 5.5rem);
  padding-bottom: 2.5rem;
}

.footer-top {
  display: grid;
  grid-template-columns: 1.5fr 1fr 1fr 1fr 1.2fr;
  gap: clamp(2rem, 4vw, 3.5rem);
  padding-bottom: 3.5rem;
  border-bottom: 1px solid rgba(255, 255, 255, 0.08);
}

.footer-brand {
  display: flex;
  flex-direction: column;
  gap: 1.2rem;
}

.footer-brand img {
  height: 44px;
  width: auto;
}

.footer-tagline {
  color: var(--color-light-blue);
  font-size: 0.95rem;
  font-weight: 500;
}

.footer-desc {
  font-size: 0.9rem;
  line-height: 1.6;
  color: #94A3B8;
}

.footer-col-title {
  color: var(--color-white);
  font-size: 0.95rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  margin-bottom: 1.25rem;
  font-family: var(--font-mono);
}

.footer-links {
  list-style: none;
  display: flex;
  flex-direction: column;
  gap: 0.75rem;
}

.footer-link {
  color: #CBD5E1;
  font-size: 0.9rem;
  text-decoration: none;
  transition: color var(--transition-fast);
}

.footer-link:hover {
  color: var(--color-light-gold);
}

.footer-contact-item {
  display: flex;
  align-items: flex-start;
  gap: 0.65rem;
  font-size: 0.875rem;
  color: #CBD5E1;
  margin-bottom: 0.75rem;
  line-height: 1.5;
}

.footer-contact-item svg {
  width: 18px;
  height: 18px;
  color: var(--color-light-gold);
  flex-shrink: 0;
  margin-top: 2px;
}

.footer-bottom {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding-top: 2rem;
  font-size: 0.85rem;
  color: #64748B;
  flex-wrap: wrap;
  gap: 1rem;
}

.footer-legal-badge {
  display: inline-flex;
  align-items: center;
  gap: 0.4rem;
  font-size: 0.8rem;
  color: var(--color-light-gold);
  background: rgba(197, 151, 77, 0.12);
  border: 1px solid rgba(197, 151, 77, 0.25);
  padding: 0.25rem 0.75rem;
  border-radius: var(--radius-sm);
}

/* Responsive Navigation Breakpoints */
@media (max-width: 1024px) {
  .nav-desktop,
  .nav-cta {
    display: none;
  }
  .mobile-toggle {
    display: block;
  }
  .footer-top {
    grid-template-columns: repeat(2, 1fr);
  }
}

@media (max-width: 640px) {
  .form-grid {
    grid-template-columns: 1fr;
  }
  .footer-top {
    grid-template-columns: 1fr;
  }
  .footer-bottom {
    flex-direction: column;
    align-items: flex-start;
  }
}