/* Buttons */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 0.5rem;
  padding: 0.875rem 1.75rem;
  font-family: inherit;
  font-size: 1rem;
  font-weight: 600;
  border-radius: 10px;
  border: 2px solid transparent;
  cursor: pointer;
  transition: all var(--transition);
  white-space: nowrap;
}

.btn-primary {
  background: var(--teal);
  color: var(--white);
  border-color: var(--teal);
}

.btn-primary:hover {
  background: var(--teal-dark);
  border-color: var(--teal-dark);
  transform: translateY(-2px);
  box-shadow: 0 6px 20px rgba(13, 148, 136, 0.35);
}

.btn-secondary {
  background: transparent;
  color: var(--navy);
  border-color: var(--gray-300);
}

.btn-secondary:hover {
  border-color: var(--navy);
  background: var(--gray-50);
}

.btn-sm {
  padding: 0.55rem 1.1rem;
  font-size: 0.875rem;
  border-radius: 8px;
}

.btn-outline-teal {
  background: transparent;
  color: var(--teal);
  border-color: var(--teal);
}

.btn-outline-teal:hover {
  background: var(--teal);
  color: var(--white);
}

/* Navigation */
.header {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 1000;
  background: rgba(255, 255, 255, 0.92);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  border-bottom: 1px solid transparent;
  transition: border-color var(--transition), box-shadow var(--transition);
}

.header.scrolled {
  border-bottom-color: var(--gray-200);
  box-shadow: var(--shadow-sm);
}

.nav {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: var(--header-height);
  gap: 1.5rem;
}

.logo {
  font-size: 1.25rem;
  font-weight: 800;
  color: var(--navy);
  letter-spacing: -0.02em;
  white-space: nowrap;
}

.logo span {
  color: var(--teal);
}

.nav-links {
  display: flex;
  align-items: center;
  gap: 0.25rem;
  list-style: none;
}

.nav-links a {
  padding: 0.5rem 0.875rem;
  font-size: 0.9rem;
  font-weight: 500;
  color: var(--gray-600);
  border-radius: 8px;
  transition: color var(--transition), background var(--transition);
}

.nav-links a:hover {
  color: var(--navy);
  background: var(--gray-100);
}

.nav-cta {
  display: inline-flex;
  align-items: center;
  padding: 0.6rem 1.25rem;
  font-size: 0.9rem;
  font-weight: 600;
  color: var(--white);
  background: var(--teal);
  border-radius: 8px;
  transition: background var(--transition), transform var(--transition);
  white-space: nowrap;
}

.nav-cta:hover {
  background: var(--teal-dark);
  transform: translateY(-1px);
}

.nav-cta-wrap {
  display: flex;
  align-items: center;
  gap: 0.5rem;
}

.nav-login {
  display: inline-flex;
  align-items: center;
  padding: 0.6rem 1.25rem;
  font-size: 0.9rem;
  font-weight: 600;
  color: var(--navy);
  border: 2px solid var(--gray-200);
  border-radius: 8px;
  transition: border-color var(--transition), background var(--transition);
  white-space: nowrap;
}

.nav-login:hover {
  border-color: var(--navy);
  background: var(--gray-50);
}

.nav-links .nav-login-mobile {
  border: 2px solid var(--gray-200);
  border-radius: 8px;
  text-align: center;
  font-weight: 600;
  color: var(--navy);
}

.nav-links .nav-login-mobile:hover {
  border-color: var(--navy);
  background: var(--gray-50);
}

.nav-toggle {
  display: none;
  flex-direction: column;
  justify-content: center;
  gap: 5px;
  width: 40px;
  height: 40px;
  background: none;
  border: none;
  cursor: pointer;
  padding: 8px;
  border-radius: 8px;
}

.nav-toggle span {
  display: block;
  width: 100%;
  height: 2px;
  background: var(--navy);
  border-radius: 2px;
  transition: transform var(--transition), opacity var(--transition);
}

.nav-toggle.active span:nth-child(1) {
  transform: translateY(7px) rotate(45deg);
}

.nav-toggle.active span:nth-child(2) {
  opacity: 0;
}

.nav-toggle.active span:nth-child(3) {
  transform: translateY(-7px) rotate(-45deg);
}

/* Feature cards */
.feature-card {
  padding: 2rem;
  background: var(--gray-50);
  border-radius: var(--radius-lg);
  border: 1px solid var(--gray-200);
  transition: transform var(--transition), box-shadow var(--transition);
}

.feature-card:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-md);
}

.feature-icon {
  width: 52px;
  height: 52px;
  background: linear-gradient(135deg, var(--teal), var(--emerald));
  border-radius: 14px;
  display: flex;
  align-items: center;
  justify-content: center;
  margin-bottom: 1.25rem;
}

.feature-icon svg {
  width: 26px;
  height: 26px;
  stroke: var(--white);
  fill: none;
  stroke-width: 2;
  stroke-linecap: round;
  stroke-linejoin: round;
}

.feature-card h3 {
  font-size: 1.125rem;
  font-weight: 700;
  color: var(--navy);
  margin-bottom: 0.625rem;
}

.feature-card p {
  font-size: 0.95rem;
  color: var(--gray-500);
  line-height: 1.65;
}

/* Course cards */
.course-card {
  background: var(--white);
  border-radius: var(--radius-lg);
  border: 1px solid var(--gray-200);
  overflow: hidden;
  display: flex;
  flex-direction: column;
  transition: transform var(--transition), box-shadow var(--transition);
}

.course-card:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-lg);
}

.course-card-top {
  padding: 1.75rem 1.75rem 1.25rem;
  border-bottom: 1px solid var(--gray-100);
}

.course-code {
  display: inline-block;
  font-size: 0.75rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.06em;
  color: var(--teal);
  background: rgba(13, 148, 136, 0.1);
  padding: 0.3rem 0.7rem;
  border-radius: 6px;
  margin-bottom: 0.75rem;
}

.course-card h3 {
  font-size: 1.25rem;
  font-weight: 700;
  color: var(--navy);
  margin-bottom: 0.25rem;
}

.course-card .course-desc {
  font-size: 0.875rem;
  color: var(--gray-500);
  margin-bottom: 1rem;
}

.course-topics {
  list-style: none;
}

.course-topics li {
  font-size: 0.85rem;
  color: var(--gray-600);
  padding: 0.35rem 0 0.35rem 1.25rem;
  position: relative;
}

.course-topics li::before {
  content: '';
  position: absolute;
  left: 0;
  top: 50%;
  transform: translateY(-50%);
  width: 6px;
  height: 6px;
  background: var(--teal);
  border-radius: 50%;
}

.course-card-actions {
  padding: 1.25rem 1.75rem 1.75rem;
  display: flex;
  gap: 0.75rem;
  margin-top: auto;
}

.course-card-actions .btn {
  flex: 1;
}

/* FAQ */
.faq-list {
  max-width: 720px;
  margin: 0 auto;
}

.faq-item {
  border: 1px solid var(--gray-200);
  border-radius: var(--radius);
  margin-bottom: 0.75rem;
  overflow: hidden;
  transition: border-color var(--transition);
}

.faq-item.active {
  border-color: var(--teal);
}

.faq-question {
  width: 100%;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
  padding: 1.25rem 1.5rem;
  background: var(--white);
  border: none;
  cursor: pointer;
  font-family: inherit;
  font-size: 1rem;
  font-weight: 600;
  color: var(--navy);
  text-align: left;
  transition: background var(--transition);
}

.faq-question:hover {
  background: var(--gray-50);
}

.faq-icon {
  width: 28px;
  height: 28px;
  border-radius: 50%;
  background: var(--gray-100);
  display: flex;
  align-items: center;
  justify-content: center;
  flex-shrink: 0;
  transition: transform var(--transition), background var(--transition);
}

.faq-item.active .faq-icon {
  transform: rotate(180deg);
  background: rgba(13, 148, 136, 0.15);
}

.faq-icon svg {
  width: 14px;
  height: 14px;
  stroke: var(--navy);
  fill: none;
  stroke-width: 2.5;
}

.faq-answer {
  max-height: 0;
  overflow: hidden;
  transition: max-height 0.35s ease;
}

.faq-item.active .faq-answer {
  max-height: 300px;
}

.faq-answer-inner {
  padding: 0 1.5rem 1.25rem;
  font-size: 0.95rem;
  color: var(--gray-500);
  line-height: 1.7;
}

/* WhatsApp float */
.whatsapp-float {
  position: fixed;
  bottom: 1.5rem;
  right: 1.5rem;
  z-index: 999;
  width: 60px;
  height: 60px;
  background: var(--whatsapp);
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  box-shadow: 0 4px 20px rgba(37, 211, 102, 0.45);
  transition: transform var(--transition), box-shadow var(--transition);
}

.whatsapp-float:hover {
  transform: scale(1.08);
  box-shadow: 0 6px 28px rgba(37, 211, 102, 0.55);
}

.whatsapp-float svg {
  width: 32px;
  height: 32px;
  fill: var(--white);
}

.whatsapp-float::after {
  content: '';
  position: absolute;
  inset: -4px;
  border-radius: 50%;
  border: 2px solid var(--whatsapp);
  animation: pulse-ring 2s ease-out infinite;
}

@keyframes pulse-ring {
  0% { transform: scale(1); opacity: 0.6; }
  100% { transform: scale(1.3); opacity: 0; }
}