* {
     padding: 0;
     margin: 0;
     box-sizing: border-box;
 }
 
 .titulo {
     display: flex;
     justify-content: center;
     margin-top: 10px;
     margin-bottom: 10px;
 }
 
 header {
     display: flex;
     justify-content: center;
     align-items: center;
     margin: 0 auto;
     font-size: 20px;
     width: 630px;
     border-radius: 10;
     height: 40px;
     gap: 180px;
     color: white;
     padding-top: 25px;
     padding-bottom: 25px;
     border-radius: 5px;
 }
 
 .memory-game {
     width: 500px;
     height: 500px;
     margin: auto;
     display: flex;
     flex-wrap: wrap;
     perspective: 1000px;
 }
 
 .memory-card {
     width: calc(25% - 10px);
     height: calc(25% - 10px);
     margin: 5px;
     position: relative;
     transform: scale(1);
     transform-style: preserve-3d;
     transition: transform 0.5s;
     box-shadow: 1px 1px 1px rgba(0, 0, 0, .3);
 }
 
 .memory-card:active {
     transform: scale(0.97);
     transition: transform 0.2s;
 }
 
 .memory-card.flip {
     transform: rotateY(180deg);
 }
 
 .front-face,
 .back-face {
     width: 100%;
     height: 100%;
     padding: 10px;
     position: absolute;
     border-radius: 5px;
     background: #5d5d5d;
     backface-visibility: hidden;
 }
 
 .back-face {
     font-size: 16;
 }
 
 .front-face {
     transform: rotateY(180deg);
 }
 
 footer {
     display: flex;
     flex-direction: column;
     width: 635px;
     height: 30px;
     margin: 0 auto;
     justify-content: center;
     align-items: center;
     margin-bottom: 10px;
     margin-top: 10px;
 }
 
 .Button1 {
     background-color: #5d5d5d;
     width: 500px;
     height: 30px;
     color: white;
 }
 
 #copyright {
     margin-top: 5px;
 }