:root{
  --bg0: #070812;
  --bg1: #0b0d1a;
  --panel: rgba(255,255,255,.06);
  --panel-2: rgba(255,255,255,.08);
  --border: rgba(255,255,255,.10);
  --border-2: rgba(255,255,255,.14);
  --text: rgba(255,255,255,.92);
  --muted: rgba(255,255,255,.68);
  --muted-2: rgba(255,255,255,.52);
  --accent: #7c5cff;
  --focus: rgba(124,92,255,.70);
  --shadow: 0 18px 55px rgba(0,0,0,.40);
  --shadow-soft: 0 10px 30px rgba(0,0,0,.25);
  --radius: 16px;
  --radius-sm: 12px;
}

*{ box-sizing:border-box; }
html, body{ min-height:100%; }
body{
  margin:0;
  font-family: Inter, system-ui, -apple-system, Segoe UI, Roboto, Arial, sans-serif;
  color: var(--text);
  background: radial-gradient(1200px 700px at 20% 0%, rgba(124,92,255,.22), transparent 60%),
              radial-gradient(900px 600px at 85% 10%, rgba(0, 184, 255, .12), transparent 55%),
              linear-gradient(180deg, var(--bg0), var(--bg1));
  overflow-x:hidden;
}

.bg{
  position: fixed;
  inset: 0;
  pointer-events: none;
  opacity: .16;
  background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='180' height='180'%3E%3Cfilter id='n'%3E%3CfeTurbulence type='fractalNoise' baseFrequency='.8' numOctaves='3' stitchTiles='stitch'/%3E%3C/filter%3E%3Crect width='180' height='180' filter='url(%23n)' opacity='.25'/%3E%3C/svg%3E");
  mix-blend-mode: overlay;
}

#loader{
  position: fixed;
  inset: 0;
  display:flex;
  align-items:center;
  justify-content:center;
  z-index: 1000;
  background: radial-gradient(900px 700px at 30% 0%, rgba(124,92,255,.22), transparent 60%),
              linear-gradient(180deg, var(--bg0), var(--bg1));
  transition: opacity .6s ease;
}
.loader-content{
  display:flex;
  flex-direction:column;
  align-items:center;
  gap: 14px;
  text-align:center;
}
#loadingLogo{
  width: 84px;
  height: auto;
  filter: drop-shadow(0 18px 38px rgba(0,0,0,.45));
  animation: floaty 1.2s ease-in-out infinite;
}
.loader-sub{
  font-size: 13px;
  color: var(--muted);
  letter-spacing: .2px;
}
@keyframes floaty{
  0%,100%{ transform: translateY(0); }
  50%{ transform: translateY(-10px); }
}
body.loaded #loader{
  opacity: 0;
  pointer-events:none;
}

.shell{
  width: 100%;
  min-height: 100%;
}
.topbar{
  position: sticky;
  top: 0;
  z-index: 50;
  display:flex;
  align-items:center;
  justify-content:space-between;
  gap: 14px;
  padding: 18px;
  border-bottom: 1px solid rgba(255,255,255,.06);
  background: linear-gradient(180deg, rgba(10,11,20,.70), rgba(10,11,20,.45));
  backdrop-filter: blur(14px) saturate(130%);
  -webkit-backdrop-filter: blur(14px) saturate(130%);
}
.topbar-left,
.topbar-right{
  display:flex;
  align-items:center;
  gap: 12px;
  min-width: 0;
}
.brand,
.nav-pill{
  display:flex;
  align-items:center;
  text-decoration:none;
  color: var(--text);
  border: 1px solid rgba(255,255,255,.08);
  background: rgba(255,255,255,.04);
  transition: transform .2s ease, background .2s ease, border-color .2s ease;
}
.brand{
  padding: 10px 12px;
  border-radius: 14px;
}
.brand:hover,
.nav-pill:hover{
  transform: translateY(-1px);
  background: rgba(255,255,255,.06);
  border-color: rgba(255,255,255,.12);
}
.brand-logo{
  width: 24px;
  height: 24px;
}
.nav-pill{
  min-height: 42px;
  padding: 0 14px;
  border-radius: 14px;
  font-size: 13px;
  font-weight: 800;
}
.page-title{
  display:flex;
  flex-direction:column;
  gap: 2px;
  min-width: 0;
}
.kicker{
  font-size: 11px;
  color: var(--muted-2);
  letter-spacing: .35px;
  text-transform: uppercase;
}
.headline{
  font-size: 15px;
  font-weight: 800;
  letter-spacing: .2px;
}

.content{
  width: min(1180px, calc(100% - 32px));
  margin: 0 auto;
  padding: 18px 0 36px;
}
.hero{
  display:grid;
  grid-template-columns: 1.3fr .7fr;
  gap: 16px;
  padding: 18px 0 10px;
  align-items: stretch;
}
.hero-title{
  font-size: clamp(22px, 2.4vw, 30px);
  font-weight: 850;
  letter-spacing: -.02em;
}
.hero-sub{
  margin-top: 8px;
  font-size: 14px;
  color: var(--muted);
  line-height: 1.45;
  max-width: 66ch;
}
.metric-card,
.filters,
.classes-shell{
  border-radius: var(--radius);
  border: 1px solid rgba(255,255,255,.12);
  background: linear-gradient(180deg, rgba(255,255,255,.08), rgba(255,255,255,.05));
  box-shadow: var(--shadow-soft);
}
.metric-card{
  padding: 16px;
  position: relative;
  overflow:hidden;
}
.metric-card::before{
  content:"";
  position:absolute;
  inset: -80px -60px auto auto;
  width: 220px;
  height: 220px;
  background: radial-gradient(circle, rgba(124,92,255,.35), transparent 65%);
  filter: blur(2px);
  pointer-events:none;
}
.metric-top{
  display:flex;
  align-items:center;
  justify-content:space-between;
  gap: 10px;
  position: relative;
}
.metric-label{
  font-size: 12px;
  font-weight: 800;
  letter-spacing: .3px;
  text-transform: uppercase;
  color: rgba(255,255,255,.78);
}
.metric-pill{
  font-size: 11px;
  font-weight: 800;
  padding: 6px 10px;
  border-radius: 999px;
  border: 1px solid rgba(255,255,255,.12);
  background: rgba(255,255,255,.06);
  color: rgba(255,255,255,.80);
}
.metric-value{
  position: relative;
  margin-top: 12px;
  font-size: 34px;
  font-weight: 900;
  letter-spacing: -.02em;
}
.metric-note{
  position: relative;
  margin-top: 6px;
  font-size: 12px;
  color: var(--muted-2);
}

.filters{
  margin-top: 8px;
  padding: 14px;
  display:grid;
  grid-template-columns: 1.5fr minmax(160px, .6fr) minmax(180px, .7fr);
  gap: 12px;
}
.search-box,
.select-box{
  display:grid;
  gap: 8px;
}
.search-box span,
.select-box span{
  color: var(--muted-2);
  font-size: 12px;
  font-weight: 800;
  letter-spacing: .12em;
  text-transform: uppercase;
}
input,
select{
  width: 100%;
  min-height: 44px;
  border-radius: 14px;
  border: 1px solid rgba(255,255,255,.10);
  background: rgba(0,0,0,.18);
  color: var(--text);
  padding: 0 12px;
  outline: none;
}
select option{
  color: #111827;
}
input:focus,
select:focus{
  border-color: rgba(124,92,255,.52);
  box-shadow: 0 0 0 4px rgba(124,92,255,.18);
}

.classes-shell{
  margin-top: 14px;
  overflow: hidden;
}
.classes-head{
  display:flex;
  align-items:center;
  justify-content:space-between;
  gap: 12px;
  padding: 16px;
  border-bottom: 1px solid rgba(255,255,255,.08);
}
.classes-title{
  font-size: 16px;
  font-weight: 900;
}
.classes-sub{
  margin-top: 4px;
  font-size: 12px;
  color: var(--muted);
}
.clear-btn{
  appearance: none;
  border: 1px solid rgba(255,255,255,.12);
  background: rgba(255,255,255,.06);
  color: var(--text);
  border-radius: 14px;
  padding: 10px 12px;
  font-weight: 850;
  cursor: pointer;
  white-space: nowrap;
}
.clear-btn:hover{
  background: rgba(255,255,255,.09);
}
.class-tabs{
  display:flex;
  gap: 8px;
  overflow-x:auto;
  padding: 14px 16px;
  border-bottom: 1px solid rgba(255,255,255,.08);
}
.class-tab{
  appearance:none;
  border: 1px solid rgba(255,255,255,.10);
  background: rgba(255,255,255,.05);
  color: rgba(255,255,255,.82);
  border-radius: 14px;
  min-height: 38px;
  padding: 0 12px;
  font-size: 12px;
  font-weight: 900;
  white-space: nowrap;
  cursor: pointer;
  transition: transform .18s ease, background .18s ease, border-color .18s ease;
}
.class-tab:hover{
  transform: translateY(-1px);
  background: rgba(255,255,255,.08);
  border-color: rgba(255,255,255,.16);
}
.class-tab.active{
  background: linear-gradient(90deg, rgba(124,92,255,.95), rgba(124,92,255,.72));
  border-color: rgba(124,92,255,.34);
  color: #0b0b12;
}
.classes-grid{
  display:grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 14px;
  padding: 16px;
}
.class-card{
  border-radius: var(--radius);
  border: 1px solid rgba(255,255,255,.10);
  background: linear-gradient(180deg, rgba(255,255,255,.075), rgba(255,255,255,.045));
  box-shadow: var(--shadow-soft);
  padding: 16px;
  position: relative;
  overflow: hidden;
}
.class-card::before{
  content:"";
  position:absolute;
  inset: -120px -80px auto auto;
  width: 260px;
  height: 260px;
  background: radial-gradient(circle, rgba(124,92,255,.18), transparent 64%);
  pointer-events:none;
}
.class-card-head{
  position: relative;
  display:flex;
  align-items:flex-start;
  justify-content:space-between;
  gap: 12px;
}
.class-kicker{
  color: var(--muted-2);
  font-size: 11px;
  font-weight: 900;
  letter-spacing: .14em;
  text-transform: uppercase;
}
.class-title{
  margin: 4px 0 0;
  font-size: 22px;
  font-weight: 900;
  letter-spacing: -.02em;
}
.class-count{
  width: 48px;
  height: 48px;
  border-radius: 50%;
  display:grid;
  place-items:center;
  border: 1px solid rgba(255,255,255,.12);
  background: conic-gradient(from -90deg, rgba(124,92,255,.95), rgba(0,184,255,.70), rgba(255,255,255,.10));
  color: #fff;
  font-weight: 900;
  box-shadow: 0 14px 30px rgba(0,0,0,.26);
}
.class-stats{
  position: relative;
  display:grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 10px;
  margin-top: 14px;
}
.class-stats div,
.info-tile{
  border-radius: 14px;
  border: 1px solid rgba(255,255,255,.08);
  background: rgba(0,0,0,.16);
  padding: 12px;
}
.class-stats strong{
  display:block;
  font-size: 18px;
  font-weight: 900;
}
.class-stats span,
.info-tile span{
  display:block;
  margin-top: 3px;
  color: var(--muted-2);
  font-size: 11px;
  font-weight: 800;
  letter-spacing: .08em;
  text-transform: uppercase;
}
.subject-list{
  position: relative;
  display:grid;
  gap: 10px;
  margin-top: 14px;
}
.subject-details{
  border-radius: 15px;
  border: 1px solid rgba(255,255,255,.09);
  background: rgba(255,255,255,.04);
  overflow:hidden;
}
.subject-details summary{
  list-style:none;
  display:flex;
  align-items:center;
  justify-content:space-between;
  gap: 12px;
  padding: 12px;
  cursor:pointer;
}
.subject-details summary::-webkit-details-marker{ display:none; }
.subject-details summary:hover{
  background: rgba(255,255,255,.045);
}
.subject-main{
  display:flex;
  align-items:center;
  gap: 12px;
  min-width: 0;
}
.subject-icon{
  width: 42px;
  height: 42px;
  border-radius: 14px;
  display:grid;
  place-items:center;
  flex: 0 0 auto;
  border: 1px solid rgba(255,255,255,.10);
  background: rgba(124,92,255,.18);
  color: rgba(255,255,255,.92);
  font-weight: 900;
}
.subject-copy{
  min-width:0;
}
.subject-name{
  color: var(--text);
  font-size: 14px;
  font-weight: 900;
  line-height: 1.25;
  word-break: break-word;
}
.subject-meta{
  margin-top: 3px;
  color: var(--muted-2);
  font-size: 12px;
  font-weight: 700;
}
.subject-side{
  display:flex;
  align-items:center;
  gap: 10px;
  flex: 0 0 auto;
}
.chevron{
  color: var(--muted);
  font-size: 24px;
  line-height: 1;
  transition: transform .2s ease;
}
.subject-details[open] .chevron{
  transform: rotate(90deg);
}
.subject-panel{
  display:grid;
  gap: 14px;
  padding: 0 12px 12px;
}
.info-grid{
  display:grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 10px;
}
.info-tile strong{
  display:block;
  margin-top: 5px;
  color: var(--text);
  font-size: 13px;
  line-height: 1.35;
  word-break: break-word;
}
.roster-head{
  display:flex;
  align-items:center;
  justify-content:space-between;
  gap: 12px;
  color: var(--muted);
  font-size: 12px;
  font-weight: 800;
}
.student-chips{
  display:flex;
  flex-wrap:wrap;
  gap: 8px;
  max-height: 220px;
  overflow:auto;
  padding-right: 2px;
}
.student-chips span{
  display:inline-flex;
  align-items:center;
  border-radius: 999px;
  border: 1px solid rgba(255,255,255,.09);
  background: rgba(255,255,255,.055);
  color: rgba(255,255,255,.82);
  padding: 7px 9px;
  font-size: 12px;
  font-weight: 750;
}
.tag{
  display:inline-flex;
  align-items:center;
  padding: 6px 10px;
  border-radius: 999px;
  border: 1px solid rgba(255,255,255,.10);
  background: rgba(255,255,255,.05);
  color: rgba(255,255,255,.82);
  font-size: 12px;
  font-weight: 800;
}
.tag.ok{
  border-color: rgba(66, 211, 146, .28);
  background: rgba(66, 211, 146, .10);
  color: #b8f7dc;
}
.capacity{
  display:grid;
  gap: 8px;
  min-width: 128px;
}
.capacity-text{
  font-weight: 900;
}
.capacity-bar{
  height: 8px;
  border-radius: 999px;
  overflow: hidden;
  background: rgba(255,255,255,.10);
}
.capacity-fill{
  height: 100%;
  width: 0%;
  border-radius: inherit;
  background: linear-gradient(90deg, rgba(124,92,255,.95), rgba(0,184,255,.76));
}
.students{
  max-width: 390px;
  color: var(--muted);
  line-height: 1.45;
}
.empty-state{
  padding: 28px 16px;
  color: var(--muted);
  text-align: center;
}
.hidden{ display:none !important; }

.state-card{
  width: min(720px, calc(100% - 32px));
  border-radius: var(--radius);
  border: 1px solid rgba(255,255,255,.12);
  background: linear-gradient(180deg, rgba(255,255,255,.085), rgba(255,255,255,.05));
  box-shadow: var(--shadow-soft);
  padding: 18px;
  position: fixed;
  left: 50%;
  top: 50%;
  transform: translate(-50%, -50%);
  z-index: 9998;
  overflow: hidden;
  text-align: center;
}
.state-card::before{
  content:"";
  position:absolute;
  inset: -60px -80px auto auto;
  width: 260px;
  height: 260px;
  background: radial-gradient(circle, rgba(124,92,255,.28), transparent 62%);
  pointer-events:none;
}
.state-icon{
  width: 48px;
  height: 48px;
  margin: 0 auto 10px;
  border-radius: 16px;
  display: grid;
  place-items: center;
  border: 1px solid rgba(255,255,255,.12);
  background: rgba(255,255,255,.06);
  color: rgba(255,255,255,.86);
  box-shadow: 0 16px 36px rgba(0,0,0,.28);
}
.state-title{
  font-size: 16px;
  font-weight: 900;
  letter-spacing: -.01em;
  margin-bottom: 6px;
}
.state-sub{
  font-size: 13px;
  color: var(--muted);
  line-height: 1.45;
  max-width: 62ch;
  margin: 0 auto 14px;
}
.state-actions{
  display:flex;
  gap: 10px;
  justify-content:center;
  flex-wrap: wrap;
}
.state-btn{
  display:inline-flex;
  align-items:center;
  justify-content:center;
  padding: 10px 12px;
  border-radius: 14px;
  border: 1px solid rgba(255,255,255,.12);
  text-decoration:none;
  font-weight: 900;
  font-size: 13px;
  letter-spacing: .15px;
  cursor: pointer;
}
.state-btn.ghost{
  background: rgba(255,255,255,.06);
  color: rgba(255,255,255,.90);
}
.state-btn.primary{
  background: linear-gradient(90deg, rgba(124,92,255,.95), rgba(124,92,255,.78));
  border-color: rgba(124,92,255,.35);
  color: #0b0b12;
}
body.state-lock::after{
  content:"";
  position: fixed;
  inset: 0;
  background: rgba(0,0,0,.35);
  backdrop-filter: blur(8px);
  -webkit-backdrop-filter: blur(8px);
  z-index: 9997;
}
body.state-lock{
  overflow: hidden;
}

@media (max-width: 900px){
  .hero,
  .filters{
    grid-template-columns: 1fr;
  }
  .classes-grid{
    grid-template-columns: 1fr;
  }
}
@media (max-width: 560px){
  .topbar{
    align-items: flex-start;
    padding: 14px 12px;
  }
  .topbar-right{
    gap: 8px;
    flex-wrap: wrap;
    justify-content: flex-end;
  }
  .nav-pill{
    min-height: 38px;
    padding: 0 11px;
    font-size: 12px;
  }
  .content{
    width: min(100% - 24px, 1180px);
  }
  .classes-head{
    align-items:flex-start;
    flex-direction: column;
  }
  .classes-grid{
    padding: 12px;
  }
  .class-stats,
  .info-grid{
    grid-template-columns: 1fr;
  }
  .subject-details summary{
    align-items:flex-start;
  }
  .subject-side{
    flex-direction: column;
    align-items:flex-end;
    gap: 4px;
  }
  .student-chips{
    max-height: 260px;
  }
}

@media (prefers-reduced-motion: reduce){
  *{ transition:none !important; animation:none !important; scroll-behavior:auto !important; }
}