Input field placeholder not visible on Ios safari

Here is my code for input field and placeholder. Don't know why its not working on ios safari but the same is working on other devices.

            .form input {
        margin-top: 30px;
        border: 1px solid #d8d8d8;
        border-radius: 5px;
        background-color: transparent;
        outline: none;
        width: 50%;
        /* padding: 18px 15px;
        font-size: 14px; */
        line-height: 40px;
        height: 50px;
        padding: 0 15px;
        font-family: "Campan";
        color: #3d8559;
        position: relative;
        }
        .form input::placeholder {
        font-size: 14px;
        transition: 400ms;
        position: absolute;
        top: 32%;
        left: 10px;
        color: #8e8e8e;
        }

I have also tried the code below but not working

::-webkit-input-placeholder {
        color: #000;
        opacity: 1;
        }
        ::-moz-placeholder {
        /* Firefox 19+ */
        color: #777;
        }
        :-ms-input-placeholder {
        color: #777;
        }
        :-moz-placeholder {
        /* Firefox 18- */
        color: #777;
        }