Check out example codes for "google sign in button". It will help you in understanding the concepts better.

Code Example 1

<div class='g-sign-in-button'>
    <div class=content-wrapper>
        <div class='logo-wrapper'>
            <img src='https://developers.google.com/identity/images/g-logo.png'>
        </div>
        <span class='text-container'>
      <span>Sign in with Google</span>
    </span>
    </div>
</div>

<style>
        *, *:before, *:after {
            box-sizing: border-box;
        }

        .g-sign-in-button {
            margin: 10px;
            display: inline-block;
            width: 240px;
            height: 50px;
            background-color: #4285f4;
            color: #fff;
            border-radius: 1px;
            box-shadow: 0 2px 4px 0 rgba(0, 0, 0, 0.25);
            transition: background-color .218s, border-color .218s, box-shadow .218s;
        }

        .g-sign-in-button:hover {
            cursor: pointer;
            -webkit-box-shadow: 0 0 3px 3px rgba(66, 133, 244, 0.3);
            box-shadow: 0 0 3px 3px rgba(66, 133, 244, 0.3);
        }

        .g-sign-in-button:active {
            background-color: #3367D6;
            transition: background-color 0.2s;
        }

        .g-sign-in-button .content-wrapper {
            height: 100%;
            width: 100%;
            border: 1px solid transparent;
        }

        .g-sign-in-button img {
            width: 18px;
            height: 18px;
        }

        .g-sign-in-button .logo-wrapper {
            padding: 15px;
            background: #fff;
            width: 48px;
            height: 100%;
            border-radius: 1px;
            display: inline-block;
        }

        .g-sign-in-button .text-container {
            font-family: Roboto,arial,sans-serif;
            font-weight: 500;
            letter-spacing: .21px;
            font-size: 16px;
            line-height: 48px;
            vertical-align: top;
            border: none;
            display: inline-block;
            text-align: center;
            width: 180px;
        }

</style>

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