buttons.css

.container {
    display: flex;
    justify-content: center;
}

.main {
	  display: flex;
	  flex-direction: column;
	  justify-content: space-around;
	  width: 250px;
	  height: 100px;
	  background: coral;
	  border-color: steelblue;
	  border-width: thick;
	  border-style: groove;
}

.guess {
    color: white;
    font-size: xx-large;
    font-weight: bold;
    font-family: arial;
    text-align: center;
    text-shadow: 0px 1px 2px black;
}

.buttons {
    display: flex;
    justify-content: space-around;
}

.submit {
    display: inline-block;
    padding: 0.35em 1.2em;
    border: 0.1em solid #FFFFFF;
    margin: 0 0.3em 0.3em 0;
    border-radius: 0.12em;
    box-sizing: border-box;
    text-decoration: none;
    font-family: 'Roboto',sans-serif;
    color: white;
    text-align: center;
    transition: all 0.2s;
    background: transparent;
}

.submit:hover {
    color: black;
    background-color: white;
}