/* =========================================================
  SANTÉ Healthcare - History / Timeline
  - White base + Deep Blue accent
  - Responsive (PC/Mobile)
  - Accessible tabs + focus styles
  ========================================================= */
:root{
  --bg:#ffffff;
  --text:#0B1B2B;
  --blue:#1E5BFF;
  --gray:#6B7280;
  --line:#E5E7EB;
  --card:#ffffff;
  --radius-lg:24px;
  --radius-md:18px;
  --shadow: 0 10px 30px rgba(11,27,43,0.08);
  --container: 1240px;
  --section-pad: 64px;
  --timeline-line-w: 2px;
  --timeline-gap: 26px;
  --transition: 220ms cubic-bezier(.2,.8,.2,1);
}
*{ 
  box-sizing:border-box; 
}
body{
  font-family: ui-sans-serif, system-ui, -apple-system, "Segoe UI", Roboto, "Apple SD Gothic Neo",
    "Noto Sans KR", "Malgun Gothic", Arial, sans-serif;
  line-height: 1.55;
  letter-spacing: -0.2px;
}
/* ---------- Layout ---------- */
.history-container,
.history-container *{
  font-family: 'Pretendard', -apple-system, BlinkMacSystemFont, system-ui, Roboto, "Helvetica Neue", "Segoe UI", "Apple SD Gothic Neo", "Noto Sans KR", "Malgun Gothic", "Apple Color Emoji", "Segoe UI Emoji", "Segoe UI Symbol", sans-serif !important;
}
.history-container{
  background: var(--bg);
  color: var(--text);
  padding: var(--section-pad) 0;
}
.hht-container{
  width: min(var(--container), calc(100% - 40px));
  margin: 0 auto;
}
/* ---------- Timeline Header (tabs) ---------- */
.timeline-head{
  display: flex;
  align-items: flex-end;
  justify-content: space-between;
  gap: 18px;
  margin-bottom: 50px;
}
.timeline-title-wrap{
  display: grid;
  gap: 8px;
}
.section-eyebrow{
  font-size: 17px;
  font-weight: 600;
  letter-spacing: 0.16em;
  text-transform: uppercase;
  color: var(--gray);
  display: inline-flex;
  align-items: center;
  gap: 10px;
}
.section-eyebrow::before{
  content:"";
  width: 14px;
  height: 2px;
  background: var(--blue);
  border-radius: 999px;
  opacity: .9;
}
.section-title{
  margin: 0;
  font-size: 35px;
  font-weight: 700;
  letter-spacing: -0.4px;
}
.tabs{
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  justify-content: flex-end;
}
.tab-btn{
  appearance: none;
  border: 1px solid var(--line);
  background: #fff;
  color: var(--text);
  padding: 10px 14px;
  cursor: pointer;
  transition: background var(--transition), border-color var(--transition), color var(--transition), transform var(--transition);
  font-size: 14px;
  line-height: 1;
  user-select: none;
}
.tab-btn:hover{
  border-color: rgba(30,91,255,0.45);
  transform: translateY(-1px);
}
.tab-btn[aria-selected="true"]{
  background: var(--blue);
  border-color: var(--blue);
  color: #fff;
}
.tab-btn:focus-visible{
  outline: 3px solid rgba(30,91,255,.35);
  outline-offset: 2px;
}
/* ---------- Timeline (PC: center line + alternating cards) ---------- */
.timeline{
  position: relative;
  display: grid;
  gap: 18px;
}
.timeline::before{
  content:"";
  position: absolute;
  top: 0;
  bottom: 0;
  left: 50%;
  width: var(--timeline-line-w);
  transform: translateX(-50%);
  background: linear-gradient(to bottom,
    rgba(30,91,255,.2),
    rgba(30,91,255,.5),
    rgba(30,91,255,.5),
    rgba(30,91,255,.2)
  );
  border-radius: 999px;
  pointer-events: none;
  box-shadow: 0 0 8px rgba(30,91,255,.3);
}
/* 선 안에서 흐르는 그라데이션 효과 */
.timeline::after{
  content:"";
  position: absolute;
  top: 0;
  bottom: 0;
  left: 50%;
  width: var(--timeline-line-w);
  transform: translateX(-50%);
  background: linear-gradient(to bottom,
    rgba(30,91,255,0) 0%,
    rgba(138,180,255,.9) 15%,
    rgba(255,255,255,.95) 20%,
    rgba(138,180,255,.9) 25%,
    rgba(30,91,255,0) 40%,
    rgba(30,91,255,0) 100%
  );
  background-size: 100% 300%;
  background-position: 0% 0%;
  border-radius: 999px;
  pointer-events: none;
  animation: gradientFlow 3s ease-in-out infinite;
  box-shadow: 0 0 15px rgba(30,91,255,.5);
}
@keyframes gradientFlow {
  0% {
    background-position: 0% 0%;
  }
  100% {
    background-position: 0% 100%;
  }
}
.timeline-item{
  display: grid;
  grid-template-columns: 1fr 58px 1fr;
  align-items: stretch;
  gap: var(--timeline-gap);
  position: relative;
  overflow: hidden;
  transition: opacity var(--transition), transform var(--transition), max-height 320ms ease;
  max-height: 420px;
  opacity: 1;
}
.timeline-item.is-hidden{
  opacity: 0;
  transform: translateY(6px);
  max-height: 0;
  margin: 0;
  pointer-events: none;
}
/* Timeline center marker */
.timeline-marker{
  position: relative;
  display: grid;
  place-items: start center;
}
.marker-dot{
  display: none; /* dot 제거 */
}
.marker-stem{
  display: none; /* 개별 stem도 제거 (중앙선만 사용) */
}
.timeline-card{
  background: var(--card);
  border: 1px solid rgba(229,231,235,0.95);
  box-shadow: var(--shadow);
  padding: 20px 22px;
  position: relative;
  overflow: hidden;
  opacity: 0;
  transform: translateY(14px);
  transition: opacity 520ms ease, transform 520ms ease;
}
.timeline-card.is-visible{
  opacity: 1;
  transform: translateY(0);
}
.timeline-card::before{
  content:"";
  position:absolute;
  left:0;
  top:0;
  width:100%;
  height: 3px;
  background: linear-gradient(90deg, rgba(30,91,255,.95), rgba(30,91,255,0));
  opacity: .9;
}
.card-year{
  font-size: 28px;
  font-weight: 800;
  letter-spacing: -0.8px;
  color: var(--blue);
  margin: 0 0 18px;
}
.card-title{
  margin: 0 0 10px;
  font-size: 16px;
  letter-spacing: -0.2px;
}
.card-bullets{
  margin: 0;
  padding-left: 18px;
  color: var(--gray);
  display: grid;
  gap: 6px;
  font-size: 14.5px;
}
/* left/right placement */
.timeline-item[data-side="left"] .timeline-card-wrap{ grid-column: 1; }
.timeline-item[data-side="left"] .timeline-spacer{ grid-column: 3; }
.timeline-item[data-side="right"] .timeline-card-wrap{ grid-column: 3; }
.timeline-item[data-side="right"] .timeline-spacer{ grid-column: 1; }
.timeline-spacer{ /* empty cell */ }
/* ---------- CTA Section ---------- */
.cta{
  margin-top: 40px;
  border-top: 1px solid var(--line);
  background:
    radial-gradient(70% 140% at 20% 0%, rgba(30,91,255,.08), rgba(30,91,255,0) 55%),
    linear-gradient(180deg, rgba(255,255,255,1), rgba(255,255,255,1));
}
.cta-inner{
  padding: 56px 0;
  display: grid;
  grid-template-columns: 1.2fr 0.8fr;
  gap: 18px;
  align-items: center;
}
.cta-title{
  margin: 0 0 10px;
  font-size: clamp(22px, 2.2vw, 30px);
  letter-spacing: -0.5px;
}
.cta-desc{
  margin: 0;
  color: var(--gray);
  max-width: 60ch;
  font-size: 15px;
}
.cta-actions{
  display: flex;
  justify-content: flex-end;
  gap: 10px;
  flex-wrap: wrap;
}
.cta-btn{
  text-decoration: none;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 10px;
  padding: 12px 16px;
  border-radius: 999px;
  border: 1px solid var(--line);
  background: #fff;
  color: var(--text);
  transition: background var(--transition), border-color var(--transition), color var(--transition), transform var(--transition);
  font-size: 14.5px;
  line-height: 1;
  min-width: 140px;
}
.cta-btn:hover{
  border-color: rgba(30,91,255,0.45);
  transform: translateY(-1px);
}
.cta-btn.primary{
  background: var(--blue);
  border-color: var(--blue);
  color: #fff;
}
.cta-btn.primary:hover{
  transform: translateY(-1px);
  filter: saturate(1.02);
}
.cta-btn:focus-visible{
  outline: 3px solid rgba(30,91,255,.35);
  outline-offset: 2px;
}
/* ---------- Credits ---------- */
.hht-credits {
  text-align: center;
  margin-top: 60px;
  padding: 20px 0;
  border-top: 1px solid var(--line);
  opacity: 0.7;
  transition: opacity 0.3s ease;
}
.hht-credits:hover {
  opacity: 1;
}
.hht-credits-text {
  margin: 0;
  color: var(--gray);
  font-size: 0.85em;
}
.hht-credits-text a {
  color: var(--gray);
  text-decoration: none;
  font-weight: 500;
  transition: color 0.3s ease;
}
.hht-credits-text a:hover {
  color: var(--text);
  text-decoration: underline;
}
/* ---------- Helpers ---------- */
.sr-only{
  position:absolute;
  width:1px;
  height:1px;
  padding:0;
  margin:-1px;
  overflow:hidden;
  clip: rect(0,0,0,0);
  white-space:nowrap;
  border:0;
}
/* ---------- Responsive ---------- */
@media (max-width: 960px){
  .history-container{
    padding: 40px 0;
  }
  .hht-container{
    width: min(var(--container), calc(100% - 32px));
  }
  .timeline-head{
    flex-direction: column;
    align-items: flex-start;
    gap: 20px;
    margin-bottom: 32px;
  }
  .timeline-title-wrap{
    gap: 6px;
  }
  .section-eyebrow{
    font-size: 11px;
    letter-spacing: 0.12em;
  }
  .section-eyebrow::before{
    width: 12px;
  }
  .section-title{
    font-size: 24px;
    letter-spacing: -0.6px;
  }
  .tabs{
    justify-content: flex-start;
    width: 100%;
    gap: 6px;
  }
  .tab-btn{
    font-size: 13px;
    padding: 8px 12px;
  }
  /* Mobile timeline: one column cards + left line */
  .timeline{
    gap: 24px;
  }
  .timeline::before{
    left: 11px;
    transform: none;
    width: 2px;
  }
  .timeline::after{
    left: 11px;
    transform: none;
    width: 2px;
  }
  .timeline-item{
    grid-template-columns: 22px 1fr;
    gap: 16px;
    max-height: 600px;
  }
  .timeline-marker{
    grid-column: 1;
    place-items: start center;
  }
  .marker-dot{
    display: none; /* 모바일에서도 dot 제거 */
  }
  .marker-stem{
    display: none; /* 모바일에서도 stem 제거 */
  }
  /* 모바일에서는 모든 카드를 오른쪽에 배치 */
  .timeline-item{
    align-items: start !important;
  }
  .timeline-marker{
    grid-column: 1 !important;
    place-items: start center !important;
    align-self: start !important;
  }
  .marker-dot{
    margin-top: 18px !important;
  }
  .marker-stem{
    top: 36px !important;
  }
  .timeline-card-wrap{
    grid-column: 2 !important;
    align-self: start !important;
  }
  .timeline-spacer{
    display:none !important;
  }
  /* 모든 data-side에 대해 동일한 스타일 강제 적용 */
  .timeline-item[data-side="left"],
  .timeline-item[data-side="right"]{
    align-items: start !important;
  }
  .timeline-item[data-side="left"] .timeline-marker,
  .timeline-item[data-side="right"] .timeline-marker{
    grid-column: 1 !important;
    place-items: start center !important;
    align-self: start !important;
  }
  .timeline-item[data-side="left"] .marker-dot,
  .timeline-item[data-side="right"] .marker-dot{
    display: none !important; /* dot 제거 */
  }
  .timeline-item[data-side="left"] .marker-stem,
  .timeline-item[data-side="right"] .marker-stem{
    display: none !important; /* stem 제거 */
  }
  .timeline-item[data-side="left"] .timeline-card-wrap,
  .timeline-item[data-side="right"] .timeline-card-wrap{
    grid-column: 2 !important;
    align-self: start !important;
  }
  .timeline-item[data-side="left"] .timeline-spacer,
  .timeline-item[data-side="right"] .timeline-spacer{
    display: none !important;
  }
  .timeline-card{
    padding: 16px;
    border-radius: 0;
  }
  .timeline-card::before{
    height: 2px;
  }
  .card-year{
    font-size: 20px;
    letter-spacing: -0.6px;
    margin: 0 0 12px;
  }
  .card-title{
    font-size: 15px;
    line-height: 1.4;
    margin: 0 0 10px;
  }
  .card-bullets{
    padding-left: 16px;
    gap: 5px;
    font-size: 13px;
    line-height: 1.5;
  }
  .cta{
    margin-top: 32px;
  }
  .cta-inner{
    grid-template-columns: 1fr;
    padding: 40px 0;
    gap: 24px;
  }
  .cta-title{
    font-size: 20px;
    margin: 0 0 8px;
  }
  .cta-desc{
    font-size: 14px;
    line-height: 1.6;
  }
  .cta-actions{
    justify-content: flex-start;
    margin-top: 0;
    gap: 8px;
  }
  .cta-btn{
    min-width: 0;
    font-size: 13px;
    padding: 10px 14px;
    flex: 1;
    max-width: 48%;
  }
  .hht-credits {
    margin-top: 32px;
    padding: 16px 0;
  }
  .hht-credits-text{
    font-size: 11px;
  }
}
@media (prefers-reduced-motion: reduce){
  *{
    scroll-behavior: auto !important;
  }
  .timeline-card,
  .timeline-item,
  .tab-btn,
  .cta-btn{
    transition: none !important;
  }
}