<div class="cp_iptxt">
  <label class="ef"><input type="text" placeholder="お名前"></label>
</div>
<div class="cp_iptxt">
  <label class="ef"><input type="text" placeholder="E-Mail"></label>
</div>

.cp_iptxt {
  position: relative;
  width: 100%;
  margin: 10px 0;
}
.cp_iptxt input[type='text'] {
  font: 15px/1.6 sans-serif;
  width: calc(100% - 20px);
  padding: 0.3em;
  color: #aaaaaa;
  border: 1px solid #ffffff;
  box-shadow: 1px 1px 2px 0 #707070 inset;
  border-radius: 4px;
  transition: 0.3s;
}
.cp_iptxt .ef input[type='text']:focus {
  outline: none;
  box-shadow: inset 1px 1px 2px 0 #c9c9c9;
}