* {
  box-sizing: border-box;
}

html {
  background-color: rgba(0, 0, 0, 0.24);
}

#app {
  max-width: 1000px;
  height: 100%;
  margin: 0 auto;
  text-align: center;
  box-shadow: rgba(0, 0, 0, 0.24) 0px 3px 8px;
  background-color: rgba(255, 255, 255, 0.76);
}
#app.narrow {
  max-width: 400px;
}
#app.fit {
  height: auto;
  margin-top: 150px;
  padding: 50px;
}

html, body {
  margin: 0;
  padding: 0;
  height: 100%;
}

header {
  box-shadow: inset 0 -8px 16px -16px #000;
  background-color: rgb(230, 230, 230);
  height: 80px;
  margin-bottom: 20px;
  position: relative;
}

div.container {
  display: flex;
  justify-content: center;
}
div.container > * {
  flex: 0 1 auto;
}
div.container.vcentered {
  align-items: center;
}
div.container.card {
  height: 100%;
}

button.giant {
  width: 300px;
  height: 300px;
  display: block;
  font-size: xx-large;
}

header .corner {
  position: absolute;
  top: 4px;
  right: 4px;
}