:root {
    --text-color: #2E2E2E;
    --card-front-color: #EED6C4;
    --card-back-color: #1a1a1a;
}


@import url('https://fonts.googleapis.com/css2?family=Libertinus+Serif:ital,wght@0,400;0,600;0,700;1,400;1,600;1,700&display=swap');

body {
  background-color: gainsboro
}

#container{
  display: flex;
  flex-wrap: wrap;
  justify-content: space-between;´
  padding: 4rem;
  gap: 3rem;
}

.cartao{
  margin: 1rem 1rem;
   background: url('img/bg-desktop.webp');
  height: 20rem;
  flex-grow: 1;
  flex-basis: calc(33% - 6rem);
}

.cartao__conteudo{
   background-color: var(--card-front-color);
  text-align: center;
  height: 100%;
  transform-style: preserve-3d;
  transition: transform 300ms ease-in-out;
}

.cartao__conteudo h3{
color: var(--text-color);
border: 1px solid var(--text-color);
text-align: left;
padding: 0.5rem;
position: absolute;
margin: 0.6rem;
border-radius: 0.6rem;
font-size: 1vw;
backface-visibility: hidden;
}

.cartao__conteudo p {
    margin-top: 1rem;
    padding: 2rem;
    margin-top: 4rem;
    font-size: 1.4vw;
}

.cartao__conteudo__pergunta p {
    color: var(--text-color);
    font-weight: 500;
    padding: 1rem;
    line-height: 1.5;
    text-align: center;
}

.cartao__conteudo__resposta p {
    color: var(--card-back-color);
    font-weight: 700;
}

.cartao.active .cartao__conteudo{
  transform: rotateY(180deg);
}

.cartao__conteudo__pergunta,
.cartao__conteudo__resposta{
  backface-visibility: hidden;
  position: absolute;
  height: 100%;
  width: 100%;
  box-sizing: border-box;
}

.cartao__conteudo__resposta{
  transform: rotateY(180deg);
  background-color: rgba(26, 26, 26, 0.2);
  border: 4px solid var(--card-back-color);
}

footer {
  background-color: black;
  color: white;
  position: fixed;
  bottom: 0;
  width: 100%;
  height: 2rem;
}

footer p{
  text-align: center;
  font-size: 0.6rem;
  margin-top: 0.5rem;
}

@media(max-width: 560px){

  body{
    background: url('img/bg-mobile.webp');
  }

  .cartao {
    flex: 1 0 calc(100% - 1rem);
  }

  .cartao__conteudo h3{
    font-size: 3vw;
  }

  .cartao__conteudo p{
    font-size: 3.8vw;
  }
}