*{
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}
body{
  display: flex;
  justify-content: center;
  align-items: center;
  min-height: 100vh;
  background: #091921;
}
body.light{
  background: #d1dae3;
}
.clock{
  width: 400px;
  height: 397px;
  display: flex;
  justify-content: center;
  align-items: center;
  border: 4px solid #091921;
  background-size: cover;
  border-radius: 50%;
  background: #091921 url(./clock.png);
  box-shadow: 0 -15px 15px rgba(255, 255, 255, 0.05),
              inset 0 -15px 15px rgba(255, 255, 255, 0.05),
              0 15px 15px rgba(0,0,0,0.3),
              inset 0 15px 15px rgba(0,0,0,0.3);
  cursor: pointer;
}
body.light .clock{
  background: #d1dae3 url(./clock.png);
  background-size: cover;
  border: 4px solid #cad3dc;
  box-shadow: -8px -8px 15px rgba(255, 255, 255, 0.5),
              10px 10px 10px rgba(0, 0, 0, 0.5),
              inset -8px -8px 15px rgba(255,255,255,0.1),
              inset 10px 10px 10px rgba(0,0,0,0.1);
}
.clock::before{
  content: '';
  position: absolute;
  width: 15px;
  height: 15px;
  background: #fff;
  border-radius: 50%;
  z-index: 100000;
}
body.light .clock::before{
  background: #008eff;
}
.clock .hour, .clock .min, .clock .sec{
  position: absolute;
}
.clock .hour, .hr{
  width: 160px;
  height: 160px;
}
.clock .min{
  width: 190px;
  height: 190px;
}
.clock .sec{
  width: 230px;
  height: 230px;
}
.clock .millisec{
  width: 280px;
  height: 280px;
}
.hr, .min , .sec, .millisec{
  display: flex;
  justify-content: center;
  position: absolute;
  border-radius: 50%;
}
.hr:before{
  content: '';
  position: absolute;
  width: 8px;
  height: 80px;
  background: #ff105e;
  z-index: 10;
  border-radius: 6px 6px 0 0;
}
.mn:before{
  content: '';
  position: absolute;
  width: 4px;
  height: 90px;
  background: #fff;
  z-index: 11;
  border-radius: 6px 6px 0 0;
}
.sc:before{
  content: '';
  position: absolute;
  width: 2px;
  height: 150px;
  background: rgb(13, 54, 235);
  z-index: 12;
  border-radius: 6px 6px 0 0;
}
.toggleClass{
  position: absolute;
  top: 30px;
  right: 150px;
  width: 20px;
  height: 20px;
  font-size: 18px;
  border-radius: 50%;
  background: #d1dae3;
  color: #d1dae3;
  font-family: consolas, sans-serif;
  cursor: pointer;
  transition: 0.5s;
  display: flex;
  align-items: center;
}
.toggleClass:before{
  position: absolute;
  content: 'Light Mode';
  left: 25px;
  white-space: nowrap;
}
body.light .toggleClass{
  background: #091921;
  color: #091921;
}
body.light .toggleClass:before{
  content: 'Dark Mode';
  left: 25px;
  white-space: nowrap;
}
.backbtn {
  position: absolute;
  font-size: 2rem;
  left: 2rem;
  top: 2.5rem;
  margin-left: 6rem;
  cursor: pointer;
  color:#fff;
}
.backbtn a{
  text-decoration: none;
  color: #fff;
}