<button class="cp_button08">button</button>

.cp_button08 {
	display: inline-block;
	width: 160px;
	padding: 1em;
	line-height: 1.4;
	cursor: pointer;
	user-select: none;
	transition: background-color 0.2s, color 0.2s, width 0.2s cubic-bezier(0.175, 0.885, 0.32, 1.275), border-radius 0.2s;
	color: #7e57c2;
	border: 1px solid #7e57c2;
	border-radius: 0.2em;
	background: transparent;
}
.cp_button08:hover {
	width: 180px;
	color: #ffffff;
	border-radius: 0.5em;
	border: 1px solid #7e57c2;
	background-color: #7e57c2;
}
.cp_button08:active {
	border-color: #5e35b1;
	background-color: #5e35b1;
}
.cp_button08:focus {
	color: #7e57c2;
	border: 1px solid #7e57c2;
}
.cp_button08:focus:hover {
	color: #ffffff;
}