* {
  margin: 0;
  padding: 0;
}
a {
  text-decoration: none;
}

body {
  background: grey url(./wall.jpg) no-repeat center center;
  background-size: cover;
}
main {
  text-align: center;
  display: flex;
  justify-content: center;
  align-items: center;
  height: 100vh;
}
kbd {
  border: 1px solid red;
  width: 4em;
  height: 4em;
  display: inline-block;
  text-transform: uppercase;
  position: relative;
}
kbd > button {
  position: absolute;
  right: 0;
  bottom: 0;
  display: none;
}
kbd:hover > button {
  display: inline-block;
}
#main {
  display: inline-block;
}
#main > div:nth-child(2) {
  margin-left: -18px;
}
#main > div:nth-child(3) {
  margin-left: -110px;
}
.key {
  width: 50px;
  height: 40px;
  background: linear-gradient(to bottom, #292929 0%, #111111 100%);
  border: 1px solid #373737;
  color: #c5c5c5;
  border-radius: 5px;
  box-shadow: 0 0 0 1px #1a1b1c, 0 0 0 2px #1f2020, 0 2px 0 2px #080808;
  font-size: 16px;
  font-family: Helvetica;
  position: relative;
}
.key img {
  width: 16px;
  height: 16px;
  position: absolute;
  left:4px;
  bottom:2px;
}
.key .text {
  position: absolute;
  left: 4px;
  top: 2px;
}
.row {
  margin: 20px;
}
.row .key {
  margin: 0 8px;
}
.wrapper {
  background: rgb(255, 255, 255, 0.3);
  border-radius: 10px;
}