style.css

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

:root {
  --text-color: white;
  --bg-url: url(./assets/bg-mobile.jpg);
  --stroke-color: rgba(255, 255, 255, 0.5);
  --surface-color: rgba(255, 255, 255, 0.1);
  --surface-color-hover: rgba(255, 255, 255, 0.05);
  --highlight-color: rgba(255, 255, 255, 0.2);
  --switch-bg-url: url(./assets/moon-stars.svg);
}

.light {
  --text-color: black;
  --bg-url: url(./assets/bg-mobile-light.jpg);
  --stroke-color: rgba(0, 0, 0, 0.5);
  --surface-color: rgba(0, 0, 0, 0.07);
  --surface-color-hover: rgba(0, 0, 0, 0.02);
  --highlight-color: rgba(0, 0, 0, 0.1);
  --switch-bg-url: url(./assets/sun.svg);
}

body {
  background-image: var(--bg-url);
  background-repeat: no-repeat;
  background-position: top center;
  background-size: cover;
  /*pode agrupar o background em uma unica propriedade e a sequencia é background:color image repeat position/size
  */
  height: 100vh;
}

body * {
  /* esse "*" serve para aplicar para todos os elementos dentro do body*/
  font-family: "Inter", sans-serif;
  color: var(--text-color);
}

#container {
  width: 100%;
  max-width: 588px;
  margin: 50px auto 0px;
  padding: 0px 24px;
}

#profile {
  text-align: center;
  padding: 24px;
}

#profile img {
  width: 112px;
  margin: auto;
}

#profile p {
  font-weight: 500;
  line-height: 24px;
  margin-top: 8px;
  /* por padão a font-size é de 16px nos navegadores*/
}

#switch {
  position: relative;
  width: 64px;
  margin: 4px auto; /* esse é um alinhamento de display block*/
}

#switch button {
  width: 32px;
  height: 32px;
  background: white var(--switch-bg-url) no-repeat center;
  border: 0;
  border-radius: 50%;
  position: absolute;
  z-index: 1; /* meio q muda o andar */
  left: 0;
  transform: translateY(-50%); /* isso é para alinhar */
  top: 50%;
  animation: slide-back 0.4s;
}

.light #switch button {
  animation: slide-in 0.4s forwards; /*forwards serve para mantar as propriedades do slide-in*/
}

#switch button.houver {
  outline: 8px solid var(--highlight-color);
}

#switch span {
  display: block;
  width: 64px;
  height: 24px;
  background: var(--surface-color);
  border: 1px solid var(--stroke-color);
  backdrop-filter: blur(4px);
  -webkit-backdrop-filter: blur(4px);
  border-radius: 9999px;
}

ul {
  list-style: none;

  display: flex;
  flex-direction: column;
  gap: 16px;
  padding: 24px 0;
}

ul li a {
  display: flex; /* esse é um alinhamento de display flex*/
  justify-content: center; /*alinha no eixo vestical */
  align-items: center; /* alinha no eixo horizontal */

  padding: 16px 24px;

  background: var(--surface-color);
  border: 1px solid var(--stroke-color);
  border-radius: 8px; /*para arredondar a borda*/

  backdrop-filter: blur(4px);
  -webkit-backdrop-filter: blur(4px);

  text-decoration: none; /* para tirar aquela linha padão de link */
  font-weight: 500;

  transition: background 0.5s;
}

/*pseudo-selector*/
ul li a:hover {
  /*quando passo o mouse por cima */
  background: var(--surface-color-hover);
  border: 1.5px solid var(--text-color);
}

#socialLInks {
  display: flex;
  justify-content: center;
  gap: 8px;
  padding: 24px 0;
  font-size: 24px;
}

#socialLInks a {
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 16px;
  border-radius: 50%;
  transition: 0.5s;
}

#socialLInks a:hover {
  background: var(--highlight-color);
  border-radius: 50%;
}

@media (min-width: 700px) {
  :root {
    --bg-url: url(./assets/bg-desktop.jpg);
  }
  .light {
    --bg-url: url(./assets/bg-desktop-light.jpg);
  }
}

@keyframes slide-in {
  from {
    left: 0;
  }
  to {
    left: 50%;
  }
}

@keyframes slide-back {
  from {
    left: 50%;
  }
  to {
    left: 0;
  }
}