:root{
  --bg:#121212;
  --panel:#1e1e1e;
  --border:#333;
  --accent:#555;
  --text:#e0e0e0;
  --code-text:#4ade80;
  --box-bg:#1a1a1a;
  --muted:#888;
}
*{box-sizing:border-box}
body{
  margin:0;
  font-family:-apple-system,BlinkMacSystemFont,"Segoe UI",Roboto,sans-serif;
  background:var(--bg);
  color:var(--text);
  height:100vh;
  overflow:hidden;
  display:grid;
  grid-template-rows:auto 1fr;
  padding:16px;
  gap:16px;
}
header{
  display:flex;
  justify-content:space-between;
  align-items:center;
  padding:0 10px;
}
.logo{
  font-weight:800;
  letter-spacing:-1px;
  font-size:20px;
}
.step-pill{
  font-size:12px;
  color:var(--muted);
  background:var(--panel);
  padding:6px 12px;
  border-radius:20px;
  border:1px solid var(--border);
}
.grid-container{
  display:grid;
  grid-template-columns:300px 1fr 1fr;
  gap:16px;
  height:calc(100vh - 80px);
}
.card{
  position:relative;
  background:var(--panel);
  border:1px solid var(--border);
  border-radius:16px;
  overflow:hidden;
  display:flex;
  flex-direction:column;
  box-shadow:0 10px 15px -3px rgba(0,0,0,.5);
}
.card-header{
  padding:12px 16px;
  border-bottom:1px solid var(--border);
  font-size:12px;
  font-weight:600;
  color:var(--muted);
  text-transform:uppercase;
  letter-spacing:.05em;
}
.side{
  padding:20px;
  display:flex;
  flex-direction:column;
  justify-content:space-between;
}
.side h3{
  margin:0;
  font-size:20px;
}
.side p#desc{
  color:var(--muted);
  font-size:14px;
  margin:10px 0;
}

textarea,iframe{
  width:100%;
  height:100%;
  border:none;
  background:transparent;
  color:var(--code-text);
  font-family:"Fira Code",monospace;
  padding:20px;
  outline:none;
  resize:none;
  font-size:14px;
  font-weight:600;
}

iframe{background:#fff}

button{
  background:var(--accent);
  color:#fff;
  border:none;
  padding:16px;
  border-radius:12px;
  font-weight:600;
  cursor:pointer;
  transition:.2s;
}
button:hover:not(:disabled){filter:brightness(1.15)}
button:disabled{
  opacity:.4;
  cursor:not-allowed;
}

code{
  background:var(--box-bg);
  padding:2px 4px;
  border-radius:4px;
  color:#ff6b6b;
  font-weight:bold;
}

.task-box{
  background:var(--box-bg);
  padding:16px;
  border-radius:8px;
  border:1px solid var(--border);
  margin-top:10px;
  font-size:14px;
  line-height:1.5;
}
.task-label{
  color:var(--text);
  font-size:11px;
  font-weight:bold;
  margin-bottom:5px;
}

.learn-label{
  color:var(--code-text);
  font-size:11px;
  font-weight:bold;
  margin-bottom:5px;
}
#learn-text{
  font-size:13px;
  color:var(--text);
}

.tab-container{
  display:flex;
  gap:8px;
  margin-bottom:12px;
  margin-top:10px;
}
.tab-btn{
  flex:1;
  padding:8px;
  font-size:12px;
  background:var(--box-bg);
  color:var(--muted);
  border:1px solid var(--border);
  border-radius:6px;
  cursor:pointer;
  transition:.2s;
}
.tab-btn.active{
  background:var(--accent);
  color:#fff;
  border-color:var(--accent);
}
.no-copy{
  -webkit-user-select:none;
  -ms-user-select:none;
  user-select:none;
}
.modal-overlay{
  position:fixed;
  inset:0;
  background:rgba(0,0,0,.8);
  backdrop-filter:blur(5px);
  display:flex;
  justify-content:center;
  align-items:center;
  z-index:1000;
  opacity:0;
  pointer-events:none;
  transition:opacity .3s ease;
}
.modal-overlay.show{
  opacity:1;
  pointer-events:auto;
}
.modal-content{
  background:var(--panel);
  border:1px solid var(--border);
  padding:32px;
  border-radius:20px;
  text-align:center;
  max-width:400px;
  box-shadow:0 20px 25px -5px rgba(0,0,0,.5);
  transform:scale(.9);
  transition:transform .3s ease;
}
.modal-overlay.show .modal-content{
  transform:scale(1);
}
.modal-title{
  margin:0 0 10px 0;
  color:var(--text);
}
.modal-desc{
  color:var(--muted);
  font-size:14px;
  line-height:1.5;
  margin-bottom:24px;
}
.complete-msg{
  text-align:center;
  grid-column:span 3;
  margin-top:20vh;
}