.secciones{
    max-width: 800px;
    margin: auto;
    display: flex;
    justify-content:space-between;
    align-items: center;
}

.cuadros{
    display: flex;
    justify-content: center;
    align-items: flex-end;
    border: 0;
    width: 333.33px;
    padding: 30px;
    height: 500px;
    
    

}

.cuadros a{
    text-decoration: none;
    color: white;
    font-size: 12px;
    cursor: pointer;
    
}
.cuadro2 a{
    color:midnightblue;
}


.cuadro1{
    background-image: url(../imagenes/cerebro1.jpg);
    background-repeat: no-repeat;
    background-size: cover;
    background-position: center;
    
}

.cuadro2{
    
    background-image: url(../imagenes/etnicos copia.jpg);
    background-repeat: no-repeat;
    background-size: cover;
    background-position: center;
   
}

.cuadro3{
    
    background-image: url(../imagenes/Ilustracion-1.gif);
    background-repeat: no-repeat;
    background-size: cover;
    background-position: center;
}

.cuadro4{
    
    background-image: url(../imagenes/cartaalatierratext.jpg);
    background-repeat: no-repeat;
    background-size: cover;
    background-position: center;
}

.cuadros:hover{
   width: 1000px;
    color: white;
    transition: .9s ease;
    opacity: 1;
    
}

.cuadro1:hover{
    color: white;
    transition: .5s ease;
    opacity: 1;
    
    
}

.cuadro2:hover{
   
    color: white;
    transition: .5s ease;
    opacity: 1;
   
    
}

.cuadro3:hover{
   
    color: white;
    transition: .5s ease;
    opacity: 1;
    
}

.cuadro4:hover{
   
    color: white;
    transition: .5s ease;
    opacity: 1;
    
    
}


.nuestro{
    display: flex;
    justify-content: center;
    font-size: 25px;
    text-decoration-line:underline;
}

.cuadros h3 {
    font-size: 15px;
    opacity: 0;
    color: black;
     margin-top: 350px;
    font-size: 10px;
}

.cuadros h3:hover{
    opacity: 1;
    color: white;
    transition: .2s ease;
    max-height: 50px;
    text-align:left;
    margin-top: 170px;
    
}

.cuadro1 h3:hover{
    opacity: 1;
    color: white;
    transition: .8s ease;
    max-height: 90px;
    text-align:left;
    background-color: #17556D;
    font-size: 9px;
    padding: 30px;
    border-radius: 10px;
}

.cuadro2 h3:hover{
    opacity: 1;
    color: white;
    transition: ..8s ease;
    max-height: 90px;
    text-align:center;
    margin-top: 300px;
    background-color: black;
    font-size: 11px;
    padding: 30px;
    border-radius: 10px;
}

.cuadro3 h3:hover{
    opacity: 1;
    color: white;
    transition: ..8s ease;
    max-height: 90px;
    text-align:center;
    margin-top: 300px;
    background-color: darkgreen;
    font-size: 9px;
    padding: 30px;
    border-radius: 10px;
}

.cuadro4 h3:hover{
    opacity: 1;
    color: white;
    transition: ..8s ease;
    max-height: 90px;
    text-align:right;
    margin-top: 300px;
    background-color: black;
    font-size: 9px;
    padding: 30px;
    border-radius: 10px;
}

@media screen and (max-width: 800px) {
  .secciones{
    max-width: 500px;;
    margin: auto;
    display: flex;
    flex-direction: column;
    justify-content:center;
    align-items: center;
  }
      
  .cuadros{
    border: 0;
    width: 333.33px;
    padding: 30px;
    height: 300px;
  }

  .cuadros a{
    text-decoration: none;
  }

  .cuadros h2{
    display: flex;
    justify-content: center;
  }

  .cuadro1{
      background-image: url(../imagenes/cerebro1.jpg);
      background-repeat: no-repeat;
      background-size: cover;
      background-position: center;
      
  }

  .cuadro2{
      
      background-image: url(../imagenes/etnicos copia.jpg);
      background-repeat: no-repeat;
      background-size: cover;
      background-position: center;
     
  }

  .cuadro3{
      
      background-image: url(../imagenes/Ilustracion-1.gif);
      background-repeat: no-repeat;
      background-size: cover;
      background-position: center;
  }

  .cuadro4{
      
      background-image: url(../imagenes/cartaalatierratext.jpg);
      background-repeat: no-repeat;
      background-size: cover;
      background-position: center;
  }

  .cuadros:hover{
     width: 333px;
      color: white;
      transition: none;
      opacity: none;
      
      
  }

  .cuadro1:hover{
      color: white;
      transition: none;
      opacity: none;
      
      
  }

  .cuadro2:hover{
     
      color: white;
      transition: none;
      opacity: none;
     
      
  }

  .cuadro3:hover{
     
      color: white;
      transition: none;
      opacity: none;
      
  }

  .cuadro4:hover{
     
      color: white;
      transition: none;
      opacity: none;
      
      
  }
     .cuadros h3:hover{
      opacity: none;
      color: white;
      transition: none;
      
      
  }

  .cuadro1 h3:hover{
      opacity: 0;
      color: white;
      transition: none;
      max-height: none;
      text-align:left;
      margin-top:none;
      background-color: #17556D;
      font-size: 9px;
      padding: 10px;
      border-radius: 10px;
  }

  .cuadro2 h3:hover{
      opacity: 0;
      color: white;
      transition: none;
      max-height: none;
      text-align:center;
      margin-top: none;
      background-color: black;
      font-size: 11px;
      padding: 10px;
      border-radius: 10px;
  }

  .cuadro3 h3:hover{
      opacity: 0;
      color: white;
      transition: none;
      max-height: none;
      text-align:center;
      margin-top: none;
      background-color: darkgreen;
      font-size: 9px;
      padding: 10px;
      border-radius: 10px;
  }

  .cuadro4 h3:hover{
      opacity: 0;
      color: white;
      transition: none;
      max-height: none;
      text-align:right;
      margin-top: none;
      background-color: black;
      font-size: 9px;
      padding: -100px;
      border-radius: 10px;
  } 
    
}