*{
  margin:0;
  padding:0;
  box-sizing:border-box;
  font-family:Arial,sans-serif;
}

body{
  background:#eef3ff;
  padding:20px;
}

.container{
  width:100%;
  max-width:1100px;
  margin:auto;
}

.header{
  text-align:center;
  margin-bottom:30px;
}

.header h1{
  font-size:42px;
  color:#111827;
  margin-bottom:10px;
}

.header p{
  color:#6b7280;
  font-size:18px;
}

.tabs{
  display:flex;
  justify-content:center;
  gap:15px;
  margin-bottom:25px;
  flex-wrap:wrap;
}

.tab-btn{
  border:none;
  background:black;
  padding:15px 28px;
  border-radius:14px;
  font-size:16px;
  font-weight:600;
  cursor:pointer;
  box-shadow:0 4px 15px rgba(0,0,0,0.08);
  transition:0.3s;
}

.tab-btn.active,
.tab-btn:hover{
  background:#wite;
  color:wite;
}

.tab-content{
  display:none;
}

.tab-content.active{
  display:block;
}

.card{
  background:white;
  padding:40px;
  border-radius:28px;
  box-shadow:0 10px 30px rgba(0,0,0,0.08);
}

.card h2{
  text-align:center;
  margin-bottom:35px;
  color:#111827;
}

.grid-2{
  display:grid;
  grid-template-columns:1fr 1fr;
  gap:25px;
}

.grid-4{
  display:grid;
  grid-template-columns:repeat(4,1fr);
  gap:20px;
  margin-top:20px;
}

.input-group{
  display:flex;
  flex-direction:column;
}

.input-group label{
  margin-bottom:10px;
  color:#374151;
  font-weight:600;
}

.input-group input{
  height:58px;
  border:2px solid #dbe4ee;
  border-radius:14px;
  padding:0 15px;
  font-size:17px;
  outline:none;
}

.checkbox-row,
.radio-row{
  display:flex;
  align-items:center;
  gap:15px;
  margin:25px 0;
  flex-wrap:wrap;
}

button{
  width:100%;
  height:58px;
  border:none;
  border-radius:16px;
  background:#2563eb;
  color:white;
  font-size:18px;
  font-weight:700;
  cursor:pointer;
  transition:0.3s;
}

button:hover{
  background:#1d4ed8;
}

.result-box{
  margin-top:30px;
  background:#f8fafc;
  border-left:5px solid #2563eb;
  padding:25px;
  border-radius:18px;
  display:none;
}

.result-title{
  font-size:28px;
  font-weight:700;
  margin-bottom:20px;
  color:#111827;
}

.result-item{
  margin-bottom:15px;
  line-height:1.8;
  color:#374151;
  font-size:18px;
}

.highlight{
  color:#2563eb;
  font-weight:700;
}

.error{
  color:red;
  font-weight:700;
}

/* TABLET */

@media(max-width:991px){

  .grid-4{
    grid-template-columns:1fr 1fr;
  }

  .card{
    padding:30px;
  }

}

/* MOBILE */

@media(max-width:600px){

  body{
    padding:15px;
  }

  .header h1{
    font-size:30px;
  }

  .tabs{
    flex-direction:column;
  }

  .tab-btn{
    width:100%;
  }

  .grid-2,
  .grid-4{
    grid-template-columns:1fr;
  }

  .card{
    padding:22px;
    border-radius:22px;
  }

  .result-title{
    font-size:24px;
  }

}