/* ==========================================================================
   [Intro Stage] 인트로 전용 스타일 모듈
   ========================================================================== */

.intro-container {
  width: 100%;
  display: flex;
  flex-direction: column;
  align-items: center;
  text-align: center;
  gap: 2rem;
}

.badge-row {
  margin-top: 0.5rem;
}

.milestone-badge {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  padding: 0.5rem 1.4rem;
  border-radius: 50px;
  background: rgba(255, 255, 255, 0.88);
  backdrop-filter: blur(12px);
  border: 1px solid rgba(255, 182, 193, 0.6);
  font-family: var(--font-display);
  font-size: 0.88rem;
  font-weight: 800;
  letter-spacing: 0.12em;
  color: #ff4d6d;
  box-shadow: 0 6px 20px rgba(255, 117, 140, 0.2);
}

.sparkle {
  animation: twinkle 2s infinite ease-in-out;
}

@keyframes twinkle {
  0%, 100% { transform: scale(1) rotate(0deg); opacity: 0.85; }
  50% { transform: scale(1.3) rotate(15deg); opacity: 1; }
}

.title-row {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 0.6rem;
}

.pre-title {
  font-family: var(--font-serif);
  font-size: clamp(1.1rem, 2vw, 1.4rem);
  font-weight: 700;
  color: #64748b;
  letter-spacing: -0.02em;
}

.hero-title {
  font-size: clamp(2.2rem, 5.2vw, 3.8rem);
  font-weight: 800;
  letter-spacing: -0.03em;
  color: #1e293b;
  line-height: 1.25;
}

.gradient-text {
  background: linear-gradient(135deg, #ff4365 0%, #ff758c 45%, #a855f7 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  display: inline-block;
}

.sub-description {
  font-size: clamp(0.95rem, 1.8vw, 1.12rem);
  color: var(--text-muted);
  line-height: 1.8;
  max-width: 680px;
  word-break: keep-all;
  margin-top: 0.5rem;
}

.course-card {
  width: 100%;
  max-width: 980px;
  padding: 1.8rem 2rem;
  text-align: left;
}

.card-header {
  margin-bottom: 1.4rem;
  text-align: center;
}

.card-tag {
  font-family: var(--font-display);
  font-size: 0.72rem;
  font-weight: 800;
  letter-spacing: 0.15em;
  color: #ff5277;
  display: block;
  margin-bottom: 0.3rem;
}

.card-title {
  font-size: 1.25rem;
  font-weight: 700;
  color: var(--text-main);
}

.timeline-grid {
  display: grid;
  grid-template-columns: repeat(5, 1fr);
  gap: 0.85rem;
}

.timeline-item {
  background: rgba(255, 255, 255, 0.75);
  border: 1px solid rgba(255, 255, 255, 0.95);
  border-radius: 14px;
  padding: 1.1rem 0.9rem;
  display: flex;
  flex-direction: column;
  gap: 0.45rem;
  transition: all 0.25s ease;
  position: relative;
}

.timeline-item:hover {
  transform: translateY(-3px);
  background: #ffffff;
  box-shadow: 0 10px 22px rgba(255, 117, 140, 0.15);
}

.step-num {
  font-family: var(--font-display);
  font-size: 0.72rem;
  font-weight: 800;
  letter-spacing: 0.06em;
  color: #ff5277;
  background: #ffe4e6;
  padding: 0.2rem 0.5rem;
  border-radius: 6px;
  align-self: flex-start;
}

.step-info strong {
  display: block;
  font-size: 0.92rem;
  font-weight: 700;
  color: var(--text-main);
  margin-top: 0.2rem;
  margin-bottom: 0.2rem;
  line-height: 1.35;
}

.step-info p {
  font-size: 0.78rem;
  color: var(--text-muted);
  line-height: 1.4;
  word-break: keep-all;
}

.action-row {
  margin-top: 0.5rem;
}

.start-btn {
  display: inline-flex;
  align-items: center;
  gap: 0.75rem;
  padding: 1.15rem 2.8rem;
  border-radius: 50px;
  border: none;
  font-family: var(--font-base);
  font-size: 1.15rem;
  font-weight: 800;
  color: #ffffff;
  background: linear-gradient(135deg, #ff4b6e 0%, #ff758c 50%, #f43f5e 100%);
  box-shadow: 0 12px 28px -4px rgba(255, 75, 110, 0.45);
  cursor: pointer;
  transition: all 0.3s cubic-bezier(0.34, 1.56, 0.64, 1);
  position: relative;
  overflow: hidden;
}

.start-btn::before {
  content: '';
  position: absolute;
  top: 0;
  left: -100%;
  width: 60%;
  height: 100%;
  background: linear-gradient(90deg, transparent, rgba(255, 255, 255, 0.35), transparent);
  transform: skewX(-20deg);
  transition: 0.75s ease;
}

.start-btn:hover {
  transform: translateY(-3px) scale(1.03);
  box-shadow: 0 18px 36px -4px rgba(255, 75, 110, 0.6);
}

.start-btn:hover::before {
  left: 140%;
}

.start-btn:active {
  transform: translateY(1px) scale(0.98);
}

.btn-arrow {
  font-size: 1.25rem;
  transition: transform 0.25s ease;
}

.start-btn:hover .btn-arrow {
  transform: translateX(5px);
}

.pulse-glow {
  animation: glowPulse 3s infinite ease-in-out;
}

@keyframes glowPulse {
  0%, 100% { box-shadow: 0 12px 28px -4px rgba(255, 75, 110, 0.45); }
  50% { box-shadow: 0 16px 36px 4px rgba(255, 75, 110, 0.7); }
}

@media (max-width: 1024px) {
  .timeline-grid {
    grid-template-columns: repeat(3, 1fr);
  }
}

@media (max-width: 768px) {
  .timeline-grid {
    grid-template-columns: 1fr;
  }
  .course-card {
    padding: 1.25rem;
  }
  .start-btn {
    width: 100%;
    justify-content: center;
    padding: 1rem 1.5rem;
    font-size: 1.05rem;
  }
}