@import url('https://fonts.googleapis.com/css2?family=Muli&display=swap');

* {
  box-sizing: border-box;
}

:root{
 --line-border-fill: #3498db;
 --line-border-empty: #e0e0e0;
}
body{
  font-family:'Muli', sans-serif;
  margin: 0;
  display: flex;
  align-items: center;
  justify-content: center;
  min-height: 100vh;
  overflow: hidden;
  background-color: #f6f7fb;
}

.container{
  text-align: center;
}

.progress-container{
  position: relative;
  display: flex;
  align-items: center;
  justify-content: space-between;
  max-width: 100%;
  width: 320px;
  margin-bottom: 30px;
}

.progress-container::before{
  content: '';
  position: absolute;
  background-color: var(--line-border-empty);
  top: 50%;
  left: 0;
  height: 4px;
  width: 100%;
  z-index: -1;
  transform: translateY(-50%);
}

.progress{
  position: absolute;
  background-color: var(--line-border-fill);
  top: 50%;
  left: 0;
  height: 4px;
  width: 0%;
  z-index: -1;
  transform: translateY(-50%);
  transition: .4s ease;
}

.circle{
  background-color: #fff;
  display: flex;
  justify-content: center;
  align-items: center;
  border-radius: 50%;
  color: #999;
  width: 30px;
  border: 3px solid var(--line-border-empty);
  transition: .4s ease;
}

.circle.active{
  border-color: var(--line-border-fill);
}

.btn{
  background-color: var(--line-border-fill);
  color: #fff;
  border: 0;
  cursor: pointer;
  font-family: inherit;
  padding: 8px 30px;
  margin: 5px;
  font-size: 14px;
  border-radius: 5px;
}

.btn:active{
  transform: scale(0.98);
}
.btn:focus{
  outline: 0;
}
.btn:disabled{
  background-color: var(--line-border-empty);
  cursor: not-allowed;
}