html{
  overflow-y: scroll;
  scrollbar-gutter: stable;
}

body{
  margin:0;
  background:#f3f5f9;
  font-family:system-ui,-apple-system,BlinkMacSystemFont,"Segoe UI",Roboto;
}

.study-wrap{
  width:100%;
  max-width:1600px;
  margin:0 auto;
  padding:40px 30px;
}

.study-tabs-page{
  display:grid;
  grid-template-columns:320px 1fr;
  gap:40px;
  align-items:start;
}

.study-tabs{
  background:#fff;
  padding:20px;
  border-radius:14px;
  height:fit-content;
  position:sticky;
  top:20px;
}

.study-tabs__head{
  font-weight:800;
  margin-bottom:15px;
  position:relative;
  padding-left:18px;
}

.study-tabs__head:before{
  content:"";
  width:10px;
  height:10px;
  background:#3d6bff;
  border-radius:50%;
  position:absolute;
  left:0;
  top:6px;
}

.study-tab{
  width:100%;
  border:1px solid #e6e9ef;
  background:#fff;
  padding:14px;
  margin-bottom:10px;
  border-radius:10px;
  font-weight:600;
  text-align:left;
  cursor:pointer;
  transition:.2s;
}

.study-tab:hover{
  background:#f4f6fb;
}

.study-tab.is-active{
  background:#3d6bff;
  color:#fff;
  border-color:#3d6bff;
}

.study-pane{
  background:#fff;
  border-radius:14px;
  padding:40px;
  min-height:520px;
}

.study-panel{
  display:none;
}

.study-panel.is-active{
  display:block;
  animation:fadeIn .2s ease;
}

@keyframes fadeIn{
  from{opacity:.6}
  to{opacity:1}
}

.study-title{
  font-size:34px;
  font-weight:700;
  margin-bottom:10px;
}

.study-desc{
  color:#6b7a96;
  margin-bottom:25px;
}

.study-subtitle{
  text-align:center;
  font-weight:800;
  margin:20px 0;
}

.study-grid{
  display:grid;
  grid-template-columns:repeat(3,1fr);
  border:1px solid #e6e9ef;
  border-radius:10px;
  overflow:hidden;
}

.study-grid a{
  padding:18px;
  text-align:center;
  text-decoration:none;
  color:#2f5cff;
  font-weight:600;
  border-right:1px solid #e6e9ef;
  border-bottom:1px solid #e6e9ef;
}

.study-grid a:nth-child(3n){
  border-right:none;
}

.study-grid a:nth-last-child(-n+3){
  border-bottom:none;
}

.study-grid a:hover{
  background:#f4f7ff;
}

.study-divider{
  height:1px;
  background:#e6e9ef;
  margin:20px 0;
}

.study-files{
  display:flex;
  flex-direction:column;
  gap:10px;
}

.study-file{
  padding:12px 14px;
  border:1px solid #e6e9ef;
  border-radius:10px;
  background:#f8fafc;
  text-decoration:none;
  color:#000;
  font-weight:600;
  display:block;
}

.study-file:hover{
  background:#f1f4fb;
}

.study-cards{
  display:grid;
  grid-template-columns:repeat(2,1fr);
  gap:15px;
}

.study-card{
  border:1px solid #e6e9ef;
  border-radius:12px;
  padding:18px;
}

.study-card__title{
  font-weight:700;
  margin-bottom:12px;
}

.study-btn{
  background:#3d6bff;
  color:#fff;
  padding:10px 16px;
  border-radius:8px;
  text-decoration:none;
  font-weight:600;
  display:inline-block;
}

.study-btn:hover{
  opacity:.9;
}

@media(max-width:1000px){
  .study-tabs-page{
    grid-template-columns:1fr;
  }

  .study-tabs{
    position:relative;
    top:auto;
  }

  .study-pane{
    padding:25px;
  }

  .study-cards{
    grid-template-columns:1fr;
  }
}