.slider {
  margin: 0 auto;
  width: 100%;
  height: 400px;
  overflow: hidden;
}

.slides {
  width: 400%;
  height: 400px;
  display: flex;
}

.slides input {
  display: none;
}

.slide {
  width: 25%;
  position: relative;
  /* transition: 1s; */
}

.slide img {
  width: 100%;
  height: 400px;
}

.manual-navigation {
  position: absolute;
  width: 100%;
  margin-top: -40px;
  display: flex;
  justify-content: center;
}

.manual-btn {
  border: 2px solid #fff;
  padding: 5px;
  border-radius: 10px;
  cursor: pointer;
  transform: 1s;
}

.manual-btn:not(:last-child) {
  margin-right: 40px;
}

.manual-btn:hover {
  background-color: white;
}

#radio1:checked~.first {
  margin-left: 0;
}

#radio2:checked~.first {
  margin-left: -25%;
}

#radio3:checked~.first {
  margin-left: -50%;
}

.navigation-auto div {
  border: 2px solid #20a6ff;
  padding: 5px;
  border-radius: 10px;
  cursor: pointer;
  transition: 1s;
}

.navigation-auto {
  position: absolute;
  width: 100%;
  margin-top: 360px;
  display: flex;
  justify-content: center;
}

.navigation-auto div:not(:last-child) {
  margin-right: 40px;
}

#radio1:checked~.navigation-auto .auto-btn1 {
  background-color: #fff;
}

#radio2:checked~.navigation-auto .auto-btn2 {
  background-color: #fff;
}

#radio3:checked~.navigation-auto .auto-btn3 {
  background-color: #fff;
}

@media(max-width: 600px) {

  .slider,
  .slides,
  .slides img {
    height: 300px;
  }

  .navigation-auto {
    margin-top: 260px;
  }
}