.header {
  border-bottom: 0.1px solid rgba(102, 102, 102, 0.1);
  width: 70%;
  margin: 0 auto;
  padding: 20px 2cm 10px;
  /* box-shadow: 0 0 2px 0 #666; */
}

.header img {
  width: 200px;
}

.hidden {
  display: none;
}

.success {
  display: block;
  color: green !important;
  font-size: 20px;
}

.error {
  display: block;
  color: red;
  font-size: 20px;
}

.wrapper {
  --input-focus: #2d8cf0;
  --font-color: #323232;
  --font-color-sub: #666;
  --bg-color: #fff;
  --bg-color-alt: #666;
  --main-color: #323232;
  position: absolute;
  top: 50%;
  left: 50%;
  /* display: flex; */
  /* flex-direction: column; */
  /* align-items: center; */
}
/* switch card */
.switch {
  transform: translateY(-200px);
  position: relative;
  display: flex;
  flex-direction: column;
  justify-content: center;
  align-items: center;
  gap: 30px;
  width: 50px;
  height: 20px;
}

.card-side::before {
  position: absolute;
  content: "Log in";
  left: -70px;
  top: 0;
  width: 100px;
  text-decoration: underline;
  color: var(--font-color);
  font-weight: 600;
}

.card-side::after {
  position: absolute;
  content: "Sign up";
  left: 70px;
  top: 0;
  width: 100px;
  text-decoration: none;
  color: var(--font-color);
  font-weight: 600;
}

.toggle {
  opacity: 0;
  width: 0;
  height: 0;
}

.slider {
  box-sizing: border-box;
  border-radius: 5px;
  border: 2px solid var(--main-color);
  box-shadow: 4px 4px var(--main-color);
  position: absolute;
  cursor: pointer;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  background-color: var(--bg-colorcolor);
  transition: 0.3s;
}

.slider:before {
  box-sizing: border-box;
  position: absolute;
  content: "";
  height: 20px;
  width: 20px;
  border: 2px solid var(--main-color);
  border-radius: 5px;
  left: -2px;
  bottom: 2px;
  background-color: var(--bg-color);
  box-shadow: 0 3px 0 var(--main-color);
  transition: 0.3s;
}

.toggle:checked + .slider {
  background-color: var(--input-focus);
}

.toggle:checked + .slider:before {
  transform: translateX(30px);
}

.toggle:checked ~ .card-side:before {
  text-decoration: none;
}

.toggle:checked ~ .card-side:after {
  text-decoration: underline;
}

/* card */

.flip-card__inner {
  width: 500px;
  height: 350px;
  position: relative;
  background-color: transparent;
  perspective: 1000px;
  /* width: 100%;
      height: 100%; */
  text-align: center;
  transition: transform 0.8s;
  transform-style: preserve-3d;
}

.toggle:checked ~ .flip-card__inner {
  transform: rotateY(180deg);
}

.toggle:checked ~ .flip-card__front {
  box-shadow: none;
}

.flip-card__front,
.flip-card__back {
  width: 100%;
  padding: 20px;
  position: absolute;
  display: flex;
  flex-direction: column;
  justify-content: center;
  -webkit-backface-visibility: hidden;
  backface-visibility: hidden;
  background: lightgrey;
  gap: 20px;
  border-radius: 5px;
  border: 2px solid var(--main-color);
  box-shadow: 4px 4px var(--main-color);
}

.flip-card__back {
  width: 100%;
  transform: rotateY(180deg);
}

.flip-card__form {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 20px;
}

.title {
  margin: 20px 0 0 0;
  font-size: 25px;
  font-weight: 900;
  text-align: center;
  color: var(--main-color);
}

.flip-card__input {
  width: 80%;
  height: 40px;
  border-radius: 5px;
  border: 2px solid var(--main-color);
  background-color: var(--bg-color);
  box-shadow: 4px 4px var(--main-color);
  font-size: 15px;
  font-weight: 600;
  color: var(--font-color);
  padding: 5px 10px;
  outline: none;
}

.flip-card__input::placeholder {
  color: var(--font-color-sub);
  opacity: 0.8;
}

.flip-card__input:focus {
  border: 2px solid var(--input-focus);
}

.flip-card__btn:active,
.button-confirm:active {
  box-shadow: 0px 0px var(--main-color);
  transform: translate(3px, 3px);
}

.flip-card__btn {
  margin: 20px 0 20px 0;
  width: 200px;
  height: 40px;
  border-radius: 5px;
  border: 2px solid var(--main-color);
  background-color: var(--bg-color);
  box-shadow: 4px 4px var(--main-color);
  font-size: 17px;
  font-weight: 600;
  color: var(--font-color);
  cursor: pointer;
}

@media only screen and (max-width: 36em) {
  .header {
    width: 100%;
    margin: 20px auto 0 auto;
    padding: 10px 0;
    /* box-shadow: 0 0 2px 0 #666; */
  }

  .header img {
    width: 100px;
  }

  .wrapper {
    position: absolute;
    top: 50%;
    left: 45%;
    transform: translate(-50%, -50%);
    /* display: flex; */
    /* flex-direction: column; */
    /* align-items: center; */
  }

  .flip-card__inner {
    width: 300px;
    /* margin: 0 auto; */
  }

  .flip-card__back {
    width: 100%;
    margin-left: -40px;
  }
}