*{
  box-sizing:border-box;
  margin:0;
  padding:0;
}

body{
  font-family:Arial, sans-serif;
  background:#f4f7fb;
  color:#172033;
  min-height:100vh;
}

header{
  background:#075e3f;
  color:white;
  padding:16px 5%;
  display:flex;
  align-items:center;
  justify-content:space-between;
  gap:20px;
  box-shadow:0 3px 15px rgba(0,0,0,.15);
}

.logo{
  font-size:22px;
  font-weight:bold;
  white-space:nowrap;
}

nav{
  display:flex;
  flex-wrap:wrap;
  justify-content:center;
  gap:8px;
}

nav a{
  color:white;
  text-decoration:none;
  padding:9px 11px;
  border-radius:7px;
  font-size:14px;
}

nav a:hover{
  background:rgba(255,255,255,.15);
}

.menu-btn{
  display:none;
  border:0;
  background:white;
  color:#075e3f;
  font-size:22px;
  padding:5px 10px;
  border-radius:6px;
}

.hero{
  max-width:1150px;
  margin:auto;
  padding:70px 20px;
  text-align:center;
}

.hero h1{
  font-size:42px;
  margin-bottom:15px;
}

.hero>p{
  font-size:18px;
  color:#667085;
  margin-bottom:40px;
}

.cards{
  display:grid;
  grid-template-columns:repeat(3,1fr);
  gap:20px;
}

.card{
  background:white;
  padding:30px 20px;
  border-radius:15px;
  text-decoration:none;
  color:#172033;
  box-shadow:0 5px 20px rgba(0,0,0,.07);
  transition:.2s;
}

.card:hover{
  transform:translateY(-5px);
  box-shadow:0 10px 25px rgba(0,0,0,.12);
}

.card span{
  font-size:38px;
}

.card h2{
  margin:12px 0 8px;
}

.card p{
  color:#667085;
}

.calculator-page{
  max-width:800px;
  margin:auto;
  padding:50px 20px;
}

.calculator-page>h1{
  text-align:center;
  margin-bottom:10px;
  font-size:35px;
}

.calculator-page>p{
  text-align:center;
  color:#667085;
  margin-bottom:30px;
}

.calculator{
  background:white;
  padding:30px;
  border-radius:18px;
  box-shadow:0 5px 25px rgba(0,0,0,.08);
}

.calculator label{
  display:block;
  margin:16px 0 7px;
  font-weight:bold;
}

.calculator input,
.calculator select{
  width:100%;
  padding:13px;
  border:1px solid #d6dbe3;
  border-radius:8px;
  font-size:16px;
  outline:none;
}

.calculator input:focus,
.calculator select:focus{
  border-color:#075e3f;
}

.calculator button{
  width:100%;
  margin-top:25px;
  padding:14px;
  border:0;
  border-radius:8px;
  background:#075e3f;
  color:white;
  font-size:17px;
  font-weight:bold;
  cursor:pointer;
}

.calculator button:hover{
  background:#064b33;
}

.result{
  background:#edf8f2;
  border-left:5px solid #075e3f;
  margin-top:25px;
  padding:20px;
  border-radius:8px;
}

.result p{
  margin:10px 0;
}

.result strong{
  color:#075e3f;
}

footer{
  background:#10251e;
  color:white;
  text-align:center;
  padding:22px;
  margin-top:30px;
}

@media(max-width:900px){

  header{
    flex-wrap:wrap;
  }

  .menu-btn{
    display:block;
  }

  nav{
    display:none;
    width:100%;
    flex-direction:column;
  }

  nav.show{
    display:flex;
  }

  nav a{
    text-align:center;
    width:100%;
  }

  .cards{
    grid-template-columns:repeat(2,1fr);
  }
}

@media(max-width:600px){

  .logo{
    font-size:17px;
  }

  .hero{
    padding:45px 15px;
  }

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

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

  .calculator-page{
    padding:35px 15px;
  }

  .calculator-page>h1{
    font-size:28px;
  }

  .calculator{
    padding:20px;
  }
}