startPage.css

------------------------------------------------------HTML
<div class="search">
    <input type="text" placeholder=" ">
    <div>
        <svg>
            <use xlink:href="#path">
        </svg>
    </div>
</div>
    
<svg xmlns="http://www.w3.org/2000/svg" style="display: none;">
    <symbol xmlns="http://www.w3.org/2000/svg" viewBox="0 0 160 28" id="path">
        <path d="M32.9418651,-20.6880772 C37.9418651,-20.6880772 40.9418651,-16.6880772 40.9418651,-12.6880772 C40.9418651,-8.68807717 37.9418651,-4.68807717 32.9418651,-4.68807717 C27.9418651,-4.68807717 24.9418651,-8.68807717 24.9418651,-12.6880772 C24.9418651,-16.6880772 27.9418651,-20.6880772 32.9418651,-20.6880772 L32.9418651,-29.870624 C32.9418651,-30.3676803 33.3448089,-30.770624 33.8418651,-30.770624 C34.08056,-30.770624 34.3094785,-30.6758029 34.4782612,-30.5070201 L141.371843,76.386562" transform="translate(83.156854, 22.171573) rotate(-225.000000) translate(-83.156854, -22.171573)"></path>
    </symbol>
</svg>
    
<!-- dribbble -->
<a class="dribbble" href="https://dribbble.com/shots/5547403-Search-input-animation" target="_blank"><img src="https://dribbble.com/assets/logo-small-2x-9fe74d2ad7b25fba0f50168523c15fda4c35534f9ea0b1011179275383035439.png" alt=""></a>



-------------------------------------------------------SCSS

$color: #fff;

.search {
    display: table;
    input {
        background: none;
        border: none;
        outline: none;
        width: 28px;
        min-width: 0;
        padding: 0;
        z-index: 1;
        position: relative;
        line-height: 18px;
        margin: 5px 0;
        font-size: 14px;
        -webkit-appearance: none;
        font-family: 'Mukta Malar';
        transition: all .6s ease;
        cursor: pointer;
        color: $color;
        & + div {
            position: relative;
            height: 28px;
            width: 100%;
            margin: -28px 0 0 0;
            svg {
                display: block;
                position: absolute;
                height: 28px;
                width: 160px;
                right: 0;
                top: 0;
                fill: none;
                stroke: $color;
                stroke-width: 1.5px;
                stroke-dashoffset: 212.908 + 59;
                stroke-dasharray: 59 212.908;
                transition: all .6s ease;
            }
        }
        &:not(:placeholder-shown),
        &:focus {
            width: 160px;
            padding: 0 4px;
            cursor: text;
            &+ div {
                svg {
                    stroke-dasharray: 150 212.908;
                    stroke-dashoffset: 300;
                }
            }
        }
    }
}

::selection {
    background: rgba(#fff, .2);
}
::-moz-selection {
    background: rgba(#fff, .2);
}