A good starting point for your CSS

kl-default.css

/*======================================*
 *====== Default CSS | Author: KL ======*
 *======================================*/
*,
*:before,
*:after {
  -webkit-box-sizing: border-box;
  -moz-box-sizing: border-box;
  box-sizing: border-box;
  text-rendering: optimizeLegibility;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  font-kerning: auto;
}
html {
  -webkit-text-size-adjust: 100%;
  background-color:#ffffff;
}
body {
  margin: 0;
  padding: 0;
  position: relative;
  font-size: 1.8em;
  line-height: 1.4;
  font-weight: 400;
  font-family: 'Open Sans', 'Source Sans Pro', Roboto, 'HelveticaNeue-Light', 'Helvetica Neue Light', 'Helvetica Neue', 'Myriad Pro', 'Segoe UI', Myriad, Helvetica, 'Lucida Grande', 'DejaVu Sans Condensed', 'Liberation Sans', 'Nimbus Sans L', Tahoma, Geneva, Arial, sans-serif;
  -webkit-text-size-adjust: 100%;
}
.clear {
  display: block;
  clear: both;
}
.clearfix:after {
  content: "";
  display: block;
  clear: both;
}
.noclear {
  clear: none;
}
/*------------------*
 *--- Typography ---*
 *------------------*/
h1,h2,h3,h4,h5,h6 {
  font-family: 'Open Sans', 'Source Sans Pro', Roboto, 'HelveticaNeue-Light', 'Helvetica Neue Light', 'Helvetica Neue', 'Myriad Pro', 'Segoe UI', Myriad, Helvetica, 'Lucida Grande', 'DejaVu Sans Condensed', 'Liberation Sans', 'Nimbus Sans L', Tahoma, Geneva, Arial, sans-serif;
  font-weight: 600;
  clear: none;
}
.serif {
  font-family: 'Merriweather', 'PT Serif', Cambria, 'Hoefler Text', Utopia, 'Liberation Serif', 'Nimbus Roman No9 L Regular', Times, 'Times New Roman', serif;
}
.sans-serif {
  font-family: 'Open Sans', 'Source Sans Pro', Roboto, 'HelveticaNeue-Light', 'Helvetica Neue Light', 'Helvetica Neue', 'Myriad Pro', 'Segoe UI', Myriad, Helvetica, 'Lucida Grande', 'DejaVu Sans Condensed', 'Liberation Sans', 'Nimbus Sans L', Tahoma, Geneva, Arial, sans-serif;
}
.cursive {
  font-family: 'Playball', 'Brush Script MT', cursive;
}
.center {
  text-align: center;
}
.caps {
  text-transform: uppercase;
}
a,
a:focus,
a:visited {
  color: #44aee3;
  outline: none;
}
a:hover {
  color: #000000;
  text-decoration: none;
}
q:before {content: '\201c'}
q:after  {content: '\201d'}
q q:before {content: '\2018'}
q q:after  {content: '\2019'}
hr {
  margin-top: 20px;
  margin-bottom: 20px;
  border: 0;
  border-top: 1px solid #b2b2b2;
  background: none;
  float: none !important;
  clear: both !important;
}
/*---------------------*
 *------ Buttons ------*
 *---------------------*/
[data-button],
[data-button]:visited,
.button,
.button:visited,
.gform_button,
.gform_button:visited,
input[type=submit] {
  box-sizing: border-box;
  -moz-box-sizing: border-box;
  text-rendering: optimizeLegibility;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  display: inline-block;
  width: auto;
  margin: .5em auto;
  padding: .4em 1.5em .5em 1.5em;
  -webkit-appearance: none;
  appearance: none;
  outline: none;
  cursor: pointer;
  background: #44aee3;
  font-weight: 600;
  font-kerning: auto;
  text-decoration: none !important;
  text-align: center;
  font-size: 1em;
  line-height: 1;
  color: #ffffff;
  text-transform: none;
  border: none;
  border-top: 1px solid transparent;
  border-left: 1px solid transparent;
  box-shadow: 1px 1px 1px rgba(0, 0, 0, 0.5);
  -moz-box-shadow: 1px 1px 1px rgba(0, 0, 0, 0.5);
  -webkit-box-shadow: 1px 1px 1px rgba(0, 0, 0, 0.5);
  border-radius: 0;
  text-shadow: none;
  -webkit-user-select: none;
  -moz-user-select: none;
  -ms-user-select: none;
  -o-user-select: none;
  user-select: none;
  transition: all 0.3s ease-in-out;
  -moz-transition: all 0.3s ease-in-out;
  -webkit-transition: all 0.3s ease-in-out;
}
[data-button]:hover,
[data-button]:focus,
.button:hover,
.gform_button:hover,
input[type=submit]:hover {
  background: #2e7ba1;
  box-shadow: 0px 0px 0px rgba(0, 0, 0, 0.5);
  -moz-box-shadow: 0px 0px 0px rgba(0, 0, 0, 0.5);
  -webkit-box-shadow: 0px 0px 0px rgba(0, 0, 0, 0.5);
  border-top: 1px solid rgba(0, 0, 0, 0.25);
  border-left: 1px solid rgba(0, 0, 0, 0.25);
}
[data-button]:active,
.button:active,
.gform_button:active,
input[type=submit]:active {
  background: #2e7ba1;
  box-shadow: 0px 0px 0px rgba(0, 0, 0, 0.75);
  -moz-box-shadow: 0px 0px 0px rgba(0, 0, 0, 0.75);
  -webkit-box-shadow: 0px 0px 0px rgba(0, 0, 0, 0.75);
  border-top: 1px solid rgba(0, 0, 0, 0.5);
  border-left: 1px solid rgba(0, 0, 0, 0.5);
}
.button-large {
  font-size: 1.5em;
  text-transform: uppercase;
}
.button-wide {
  padding: .4em 1.6em .36em 1.6em;
}
/*--- Line Button Theme ---*/
[data-button="line"],
[data-button="line"]:hover,
[data-button="line"]:focus,
[data-button="line"]:active,
[data-button="line"]:visited {
  background: transparent;
  border: 1px solid rgba(255,255,255,0.75);
  color: #ffffff !important;
  border-radius: 0;
  box-shadow: none;
}
[data-button="line"]:hover,
[data-button="line"]:focus {
  box-shadow: inset 0 0 2px rgba(0, 0, 0, 0.5);
  text-shadow: 0 0 2px rgba(0, 0, 0, 0.5);
}
[data-button="line"]:active {
  box-shadow: inset 0 0 2px rgba(0, 0, 0, 1);
  text-shadow: 0 0 2px rgba(0, 0, 0, 1);
}
/*--------------------------*
 *--- Custom List Styles ---*
 *--------------------------*/
ul {
  margin: 0 0 1.5em 0;
  padding: 0 0 0 20px;
}
ul li {
  padding: 0.25em 0;
}
/* CheckList Defaults */
ul.checklist,
ul.checkbox {
  list-style: none;
  padding-left: 2.0em;
  font-weight: 400;
}
ul.checklist li,
ul.checkbox li {
  padding: 0;
  margin: 5px 0;
}
ul.checklist li:before,
ul.checkbox li:before {
  font-family: "FontAwesome";
  display :block;
  float: left;
  font-size: inherit;
  line-height: inherit;
  margin-left: -1.5em;
  color: #eccc2c;
}
ul.checklist.check-black li:before,
ul.checkbox.check-black li:before {
  color: #000000;
}
/* Check */
ul.checklist li:before {
  content: "\f00c";
}
/* CheckBox */
ul.checkbox li:before {
  content: "\f046";
}
/*--- Custom Icon lists ---*/
/* CheckList Defaults */
ul.icon-list {
  display: inline-block;
  list-style: none;
  padding-left: 50px;
  font-weight: 400;
}
ul.icon-list li {
  display: block;
  padding: 0;
  margin: 15px 0;
  line-height: 1.4em;
  vertical-align: middle;
}
ul.icon-list li span,
ul.icon-list li a {
  vertical-align: middle;
}
ul.icon-list li:after {
  content: "";
  display: block;
  clear: both;
}
ul.icon-list li:before {
  content: "\f00c";
  font-family: "FontAwesome";
  display: inline-block;
  float: left;
  line-height: inherit;
  margin-left: -41px;
  color: #eccc2c;
  width: 32px;
  height: 32px;
  font-size: 0.9em;
  line-height: 32px;
  font-weight: 400;
  color: #ffffff;
  background: #eccc2c;
  border-radius: 50%;
  text-align: center;
  vertical-align: middle;
}
ul.icon-list.icon-black li:before {
  background: #000000;
}
ul.icon-list li[data-icon="phone"]:before {
  content: "\f10b";
  font-size: 1.5em;
}
ul.icon-list li[data-icon="email"]:before {
  content: "\f0e0";
}
ul.icon-list li[data-icon="address"]:before {
  content: "\f041";
}
/*--- Leaf List ---*/
ul.icon-list[data-list="leaf"] {
  margin: 0 0 20px 0;
  padding-left: 2.5em;
}
ul.icon-list[data-list="leaf"] li:before {
  content: "\f06c";
  color: #44aee3;
  padding: 0;
  margin-left: -1.75em;
  font-size: 1em;
  line-height: 1em;
  width: 1em;
  height: 1em;
  line-height: inherit;
  background: none;
}
/*--- Auto Numbering Ordered lists ---*/
ol.circle-list {
  counter-reset: section;
  margin:0;
  padding:0;
  padding-left:3.2em;
  list-style:none;
}
ol.circle-list li {
  counter-increment: section;
  display:block;
  padding:15px 0;
  vertical-align:middle;
  line-height:1em;
}
ol.circle-list li:before {
  content: counter(section);
  display: inline-block;
  margin-right: 10px;
  margin-left: -1.75em;
  margin-left: calc(-1.6em - 10px);
  padding: 0;
  width: 1.6em;
  height: 1.6em;
  font-size: 1.5em;
  line-height: 1.6em;
  font-weight: 400;
  color: #ffffff;
  background: #eccc2c;
  border-radius: 50%;
  text-align: center;
  vertical-align: middle;
}