How to customize Subsription Form in JetPack?

Something like this should do the trick:

.jetpack_subscription_widget {
  height: 80px;
}

.jetpack_subscription_widget #subscribe-email,
.jetpack_subscription_widget #subscribe-submit {
  margin: 0;
  padding; 0;
  float: left;
}

.jetpack_subscription_widget #subscribe-email {
  width: 73%;
}

.jetpack_subscription_widget #subscribe-submit {
  width: 27%;
}

.jetpack_subscription_widget #subscribe-email input,
.jetpack_subscription_widget #subscribe-submit input {
    width: 100%;
    height: 34px;
    padding: 6px 12px;
    font-size: 14px;
    line-height: 1.42857143;
    color: #555;
    background-color: #fff;
    background-image: none;
    border: 1px solid #ccc;
    border-top-left-radius:4px;
    border-bottom-left-radius:4px;
    border-top-right-radius:0;
    border-bottom-right-radius:0;
    -webkit-box-shadow: inset 0 1px 1px rgba(0,0,0,.075);
    box-shadow: inset 0 1px 1px rgba(0,0,0,.075);
    -webkit-transition: border-color ease-in-out .15s,-webkit-box-shadow ease-in-out .15s;
    -o-transition: border-color ease-in-out .15s,box-shadow ease-in-out .15s;
    transition: border-color ease-in-out .15s,box-shadow ease-in-out .15s;
}

.jetpack_subscription_widget #subscribe-email input:focus,
.jetpack_subscription_widget #subscribe-submit input:focus {
    border-color: #66afe9;
    outline: 0;
    -webkit-box-shadow: inset 0 1px 1px rgba(0,0,0,.075),0 0 8px rgba(102,175,233,.6);
    box-shadow: inset 0 1px 1px rgba(0,0,0,.075),0 0 8px rgba(102,175,233,.6);
}

.jetpack_subscription_widget #subscribe-email input::-moz-placeholder,
.jetpack_subscription_widget #subscribe-submit input::-moz-placeholder {
    color: #999;
    opacity: 1;
}

.jetpack_subscription_widget #subscribe-email input:-ms-input-placeholder,
.jetpack_subscription_widget #subscribe-submit input:-ms-input-placeholder {
    color: #999;
}

.jetpack_subscription_widget #subscribe-email input::-webkit-input-placeholder,
.jetpack_subscription_widget #subscribe-submit input::-webkit-input-placeholder {
    color: #999;
}

.jetpack_subscription_widget #subscribe-submit input[type="submit"] {
    background-color: #3ae87c;
    border-color: transparent;
    color: #fff;
    border-top-right-radius:4px;
    border-bottom-right-radius:4px;
    border-top-left-radius:0;
    border-bottom-left-radius:0;
}

#footer-sidebar2 .widget_search  {
  clear: both;
}

Thank you so much! It helped! ??

The only thing is that the hover color function disappeared, is there any solution?

This should help:

.jetpack_subscription_widget #subscribe-submit input[type="submit"]:hover {
      background-color: #74e8a0;
}

Thank you very much!

It’s perfect ??