<h1>セミフラットボタンの基本</h1>
<button class="buttonA">BUTTON</button>
<button class="buttonB">BUTTON</button>

<h1>スキューモーフィズムを意識した押してる感のあるボタン</h1>
<button class="buttonC">BUTTON</button>
<button class="buttonD">BUTTON</button>
<button class="buttonE">BUTTON</button>

<h1>もちろん角丸でもフラット</h1>
<button class="buttonF">BUTTON</button>
<button class="buttonG">BUTTON</button>

<h1>ほわっと浮く感じ</h1>
<button class="buttonH">BUTTON</button>
<button class="buttonI">BUTTON</button>
<button class="buttonJ">BUTTON</button>
body {
  background-color: rgba(106,135,194,.4);
}
h1 {
  margin: 20px 20px 10px;
  font-size: 85%;
}

button {
	margin: 0 20px 40px;
	padding: 1em 2em;
	border: none;
	display: inline-block;
  background-color: #5A7AB3;
  box-shadow: 0 6px #4063A4;
  font-size: 114%;
  line-height: 1;
  color: #fff;
  position: relative;
	cursor: pointer;
}

/* buttonA */
.buttonA {
  border-radius: 2px;
  box-shadow: 0 6px #4063A4;
}
.buttonA:active {
	box-shadow: 0 0 #4063A4;
	top: 6px;
}

/* buttonB */
.buttonB {
  border-radius: 2px;
  box-shadow: 0 6px #4063A4;
}
.buttonB:hover {
	box-shadow: 0 5px #4063A4;
	top: 1px;
}
.buttonB:active {
	box-shadow: 0 0 #4063A4;
	top: 6px;
}

/* buttonC */
.buttonC {
  border-radius: 2px;
  box-shadow: 0 6px #4063A4;
  top: 0;
  transition: .2s all;
}
.buttonC:hover {
  border-radius: 2px;
  box-shadow: 0 6px #4063A4;
  top: 0;
  transition: .2s all;
  opacity: .8;
}
.buttonC:active {
	box-shadow: 0 1px #4063A4;
	top: 5px;
}

/* buttonD */
.buttonD {
  border-radius: 2px;
  box-shadow: 0 6px #4063A4;
  top: 0;
  transition: .2s all;
}
.buttonD:hover {
	box-shadow: 0 5px #4063A4;
	top: 1px;
}
.buttonD:active {
	box-shadow: 0 0 #4063A4;
	top: 6px;
}

/* buttonE */
.buttonE {
  border-radius: 2px;
  box-shadow: 0 6px #4063A4;
  top: 0;
  transition: .2s box-shadow,.2s top,.4s background;
}
.buttonE:hover {
	box-shadow: 0 5px #4063A4;
	top: 1px;
}
.buttonE:active {
  background-color: #4163A7;
	box-shadow: 0 0 #4063A4;
	top: 6px;
}

/* buttonF */
.buttonF {
  border-radius: .5em;
  box-shadow: 0 6px #4063A4;
  top: 0;
  transition: .2s box-shadow,.2s top,.4s background;
}
.buttonF:hover {
	box-shadow: 0 5px #4063A4;
	top: 1px;
}
.buttonF:active {
  background-color: #4163A7;
	box-shadow: 0 0 #4063A4;
	top: 6px;
}

/* buttonG */
.buttonG {
  border-radius: 1.5em;
  box-shadow: 0 6px #4063A4;
  top: 0;
  transition: .2s box-shadow,.2s top,.4s background;
}
.buttonG:hover {
	box-shadow: 0 5px #4063A4;
	top: 1px;
}
.buttonG:active {
  background-color: #4163A7;
	box-shadow: 0 0 #4063A4;
	top: 6px;
}

/* buttonH */
.buttonH {
  border-radius: 3px;
	box-shadow: 0 1px 1px rgba(0,0,0,.5);
  top: 0;
  transition: .2s all;
}
.buttonH:hover {
  top: -2px;
	box-shadow: 0 2px 10px rgba(0,0,0,.5);
}
.buttonH:active {
	box-shadow: 0 1px 1px rgba(0,0,0,.5);
	top: 0;
}

/* buttonI */
.buttonI {
  border-radius: 3px;
	box-shadow: 0 1px #4063A4;
  top: 0;
  transition: .2s all;
}
.buttonI:hover {
  top: -3px;
	box-shadow: 5px 5px #4063A4;
}
.buttonI:active {
	box-shadow: 0 1px #4063A4;
	top: 0;
}

/* buttonJ */
.buttonJ {
  border-radius: 3px;
	box-shadow: 0 2px 10px rgba(0,0,0,.5);
  top: 0;
  transition: .2s all;
}
.buttonJ:hover {
  top: 0;
	box-shadow: 0 2px 2px rgba(0,0,0,.5);
}
.buttonJ:active {
	box-shadow: 0 1px 1px rgba(0,0,0,.5);
	top: 1px;
}
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