Please can someone critique my code, finished project trying to improve

/* ================================= 
  Base Element Styles
==================================== */

* {
    box-sizing: border-box;
}

body {
    font-family: 'Varela Round', sans-serif;
    line-height: 1.6;
    color: #3a3a3a;
}

p {
    font-size: .95em;
    margin-bottom: 1.8em;
}

h2,
h3,
a {
    color: #093a58;
}

h2,
h3 {
    margin-top: 0;
}

a {
    text-decoration: none;
}

img {
    max-width: 100%;
}

/* ================================= 
  Base Layout Styles
==================================== */

/* ---- Navigation ---- */

.main-nav {
  margin-top: 5px;
}
.name {
    font-size: 1.25em;
  margin:0;
}

.name a,
.main-nav a {
    text-align: center;
  display:block;
  padding: 10px 15px;

}

.main-nav a {
    font-size: .95em;
    color: #3acec2;
    text-transform: uppercase;
}

.main-nav a:hover {
    color: #093a58;
}

/* ---- Layout Containers ---- */
.main-header {
  padding-top: .5em;
  padding-bottom: .5em;
}

.banner {
    color: #fff;
    background: #3acec2;
  text-align:center;
  padding-top: 50px;
  margin-bottom:75px;
  padding-bottom: 25px;
}

.col {
  padding-right: 1em;
  padding-left: 1em;
}
.main-footer {
    background: #d9e4ea;
    padding: 2em 0;
    margin-top: 30px;
  text-align: center;
}

/* ---- Page Elements ---- */

.logo {
    width: 190px;
}

.headline {
  margin-bottom: 0;

}


/* ================================= 
  Media Queries
==================================== */

@media (min-width: 768px) {

.container {
  width: 90%;
  margin: 0 auto;
}

.name {
  float:left;
}

.main-nav {
  float: right;
}

.main-nav li {
  float:left
}

.tagline {
  font-size: 1.4em;
}

.feat-img {
        width: 450px;
    float: left;
    margin-right: 25px;
    margin-top: 5px;
    margin-bottom: 25px;
}

.secondary,
.primary {
  display:inline-block;
  margin-left: -4px;
  vertical-align: top;
}

.secondary {
  width: 40%;
}

.primary {
  width: 60%;
}


    /* ---- Float clearfix ---- */

    .clearfix::after {
        content: " ";
        display: table;
        clear: both;
    }

}

@media (min-width: 960px) {

.primary {
  width: 50%;
}

.secondary {
  width: 25%;
}

.tertiary{
  width: 25%;
}

.col {
  float:left;
}
.main-footer{
  clear: both;
}
}