How can I change my post font size and line spacing?

I am using the Indore theme for my blog at

How can I increase the font size and line spacing of my posts (the current view is too small and compact). Any help on this will be greatly appreciated.

Thanks.

Here is the stylesheet code:

/*
Theme name: Indore
Theme URI:https://preuro.eu/indore-theme/
Description: A two-columned wordpress theme with customizable header. Fixed-width, two columns and two dynamic sidebars, widget ready theme.
Tags: light, white, fixed-width, three-columns, sticky-post, custom-header
Author: Stratus
Author URI:https://preuro.eu/
Version: 1.0.1

*/
a img {border: none;}

img {border: none;}

ol, ul {
list-style: none;
}

body {
font-size: 12px;
font-family: ‘Arial’, Verdana, Sans-Serif;
background-image: url(images/bg.jpg);
color: #666666;
margin: 0;
padding: 0;
text-align:center;

}

.right {
text-align:right;
}
.alignleft{
float:left;
margin-right:5px;
}
.alignright{
float:right;
margin-left:5px;
}
.center, .aligncenter{
margin:auto;
text-align:center;
}
.clear {
clear:both;
}
/* Main style of links */
a:link,a:visited{
color:#5C6FA3;
text-decoration:none;
}
a:hover, a:active{
color: #990000;

}
/* Top and bottom areas */

.menu {
text-transform:uppercase;
width:850px;
height:15px;
padding:10px;
text-align: center;

}

.menu li {
float:left;

}

.menu li.last {
background:none;

}

.menu a {
color:#000;
font-weight:bold;
padding:0 14px;
display:block;
line-height:2.2;
text-align: center;
}

.menu a:hover {
color:#fff;
text-decoration:none;
background-color:#990000;
}

#top{

height:0px;
width:100%;
}
#bottom{
height:52px;
width:100%;
}
/* The width and style of the actual blog area */
#page {
background: #f9f9f9;

width: 850px;
margin:0 auto;
padding:0 4px 0 2px;
}
/* Headers used within the blogposts (h1-h3 are used elsewhere on the pages and should not be used in posts)*/
h4,h5,h6{
font-size:12px;
font-family: Arial, Helvetica, sans-serif
}
h4 {font-size: 12px;}
/* Deal with the header */
#header{
margin:0px;
padding:0px;
width:100%;
text-align:right;
}
#header h1{
margin: 10px 20px 20px 0;
font-size:30px;
text-transform:uppercase;
font-family: Arial, Helvetica, sans-serif;
}
#header h1 a:link, #header h1 a:visited {
color: #fff;
text-decoration:none;
}
#header h1 a:hover, #header h1 a:active {
color: #990000;
font-weight:bold;

}
#header .description{
color: #cccccc;
font-weight:bold;
font-style: normal;
font-family: Arial, Helvetica, sans-serif;
padding: 0 20px 0 0;
}
#header_left{
float:left;
width:500px;
height:45px;
border:0px;
text-align:left;
padding-left:10px;
}
html>body #header_left{
}
#header-right{
float:right;
width:325px;
margin:0px;
padding:0px;
}
#header-right p{
text-align:justify;
margin:0px;
padding:0 10px 0 0;
}
fieldset{
border:0px;
margin:0px;
padding:10px 0 0px 0;
}
#search{border:none;}
.search{border:0px;}
#srcinput {
font-size:12px;
width:145px;
margin: 1px 0px;
border: 1px;
background:#eeeeee;
padding: 2px;
border-color:#f2f2f2;
border-style:solid;
}
#srcbutton{
font-size:12px;
margin: auto 0px;
border-width:1px;
background: #f2f2f2;
padding: 1px 2px;
border:solid 1px #CCCCCC;
}

.srcform{
border:no;}
.srcinput {
font-size:9px;
width:140px;
margin: 1px 0px;
border: 1px;
background:#eeeeee;
padding: 2px;
border-color:#eeeeee;
border-style:solid;
}
.srcbutton{
font-size:9px;
margin: auto 0px;
border:1px solid #FFFFFF;
background: #f2f2f2;
padding: 1px 2px;

}

#header-right #search{margin-top:13px;}
/* Using header right as a dynamic sidebar requires these as well */
#header-right h2{

font-size:5px;
}
/* Deal with left, right and bottom sidebars */
#sidebar-right{
background-color:#999999;
float: left;
margin:10px 0px 0px 2px;
width:240px;
padding:0px 7px 2px 7px;
font-size:11px;
font-weight:400;
border-bottom:thick #CCCCCC;
/* text-transform:uppercase; */
}
#sidebar-left{
font:Arial, Helvetica, sans-serif;
color:#CCCCCC;
font-size:14px;
text-transform:lowercase;
font-weight:bolder;
float:left;
margin:10px 2px 0px 0;
width:210px;
padding:2px 7px 2px 15px;
}
#sidebar-bottom {
background-color:#999999;
border-top: 1px solid #999999;
padding-top: 3px;
margin:5px auto;
}
#sidebar-bottom .widget_bottom {
background-color: #CCCCCC;
float:left;
list-style-type:none;
text-align:center;
margin:0 10px;
display:inline;
width:191px;
}
#sidebar-right a:link,
#sidebar-left a:link,
#sidebar-bottom a:link,
#sidebar-right a:visited,
#sidebar-left a:visited,
#sidebar-bottom a:visited{
color:#fff;
font-size:12px;
font-weight:bolder;
text-transform:uppercase;
}
#sidebar-right a:hover,
#sidebar-left a:hover,
#sidebar-bottom a:hover,
#sidebar-right a:active,
#sidebar-left a:active,
#sidebar-bottom a:active{
color:#fff;
text-decoration: none;
}
#sidebar-right ul,
#sidebar-left ul{
list-style-type: none;
margin:0;
padding:0;
text-align:left;
}
#sidebar-bottom ul{
background-color:#999999;
list-style-type: none;
margin:0;
padding:0;
text-align:left;
}
#sidebar-right li li,
#sidebar-left li li,
#sidebar-bottom li li {
background-color:#999999;
margin:1px 0;
padding:4px 1px 3px 5px;
}
#sidebar-right li li:hover,
#sidebar-left li li:hover,
#sidebar-bottom li li:hover {
color:#fff;
font-weight:700;
background:#990000;
}
#sidebar-right .current_page_item,
#sidebar-left .current_page_item,
#sidebar-bottom .current_page_item,
#sidebar-right .current-cat,
#sidebar-left .current-cat,
#sidebar-bottom .current-cat{
background-color:#999999;
}
#sidebar-right h2,
#sidebar-left h2,
#sidebar-bottom h2{
text-align:left;
padding:0 0 4px 4px;
color:#676767;
font-size:15px;
text-transform: uppercase;
font-family: Arial, Georgia, Serif;
font-weight:bold;
border-bottom:#CCCCCC solid 1px;
}
#sidebar-right p,#sidebar-left p{
font-size:12px; text-align:center;
font-weight:bold;
}
/* Show calendar in bottom sidebar */
#calendar-bottom table{
margin:auto;
width:90%;
}
#calendar-bottom a:link,
#calendar-bottom a:visited {
font-weight:bold;
color:#5C6FA3;
}
#calendar-bottom a:hover,
#calendar-bottom a:active{
color:#283d5a;
text-decoration:none;
}
#calendar-bottom #today {
background:#F3F0F6;
}

.divider{
height:5px;
padding:0;
margin:0;
}
.border_hr_thin{
height:13px;
width:100%;
margin:auto;
}
/* Deal with content (all styles used in index.php) */
#content {
text-align:left;
width:570px;
padding:5px 10px;
float:left;
margin-top:5px;
min-height:570px;

border-left:1px solid #e1e0e0;
}
html>body #content{width:570px;}
#content h1{
margin: 10px 0 10px 0;
font-family: Arial, Helvetica, sans-serif;
text-transform:uppercase;
text-shadow:#999999;
font-size:20px;
}
#content h2{
margin: 10px 0 10px 0;
font-family: Arial, Helvetica, sans-serif;
text-transform:uppercase;
text-shadow:#999999;
font-size:15px;
}
#content h2.postheader{ margin: 10px 0 1px 0;}
#content h4.{margin: 14px 0 1px 0;
text-transform: uppercase; }
#content h2 a:link, #content h2 a:visited {
color: #336699;
text-decoration:none;
}
#content h2 a:hover, {
color: #fff;
background-color:#990000;
padding:3px 10px 3px 10px;
}
#content .post-info{
font-size:10px;
font-variant: normal;
}
#content .widgettitle{
font-size:10px;
font-weight:bold;
margin: 5px 0 2px 0;
}
#content blockquote{
padding:10px;
margin:10px 20px;
color: #6C5B7E;
border:#666666 solid 1px;
}
#content q {
quotes: ‘”‘ ‘”‘ “‘” “‘”;
color: #6C5B7E;
}
#content cite { color: #6C5B7E;}
#content .css{ color:#3A80FF;}
#content .php{ color:#3E6E3E;}
#content .entry {
text-align:justify;
margin: 5px 7px;
}
#content .entry ul, #content .entry ol{
margin: 3px;
padding:0 0 0 25px;
}
#content .postmetadata{font-size: 10px;}
#content .post{
margin: 0 0 20px 0;
padding: 1px 10px 0 10px;
}
#content .sticky {
border-bottom: #666666 solid 3px;}
#content .wp-caption, .caption{
border:thin solid #676767;
background-color: #F3F0F6;
padding: 5px 2px;
-moz-border-radius: 3px;
-khtml-border-radius: 3px;
-webkit-border-radius: 3px;
border-radius: 3px;
}
#content .wp-caption{ text-align:center;}
#content img,
#content a img {border: none; padding:5px;}

#content .wp-smiley{border:0 !important;}
#content .wp-caption-text{
margin:2px;
padding:5px 3px 0px 3px;
}
#content .not-found{color:#676767;}
#content .search{margin-top:15px;}
#content .search fieldset{border:0;}
dl,dt,dd{margin:0 10px;}
dt{
font-weight:bold;
padding:6px 0 0 0;
}
.navigation .alignleft,
.navigation .alignright{
width:222px;
min-height:21px;
padding:10px 0 10px 0;
}
.navigation .alignright{
text-align:right;
}
/* Special styles used by image.php to show an image attachment */
.attachment{
text-align:center;
margin:0 auto;
}
.caption{
width:310px;
margin:15px auto;
}
.attachment p {
padding:0;
margin:7px auto 2px auto;
}
/* Special styles used by archives.php (archives page) */
.archive{
width:200px;
padding: 2px 20px;
}
/* Special styles used by links.php (links page) */
.archive{padding: 2px 20px;}
/* Special styles used by children.php */
#list-subpages{
margin:0 10px;
}
#list-subpages ul{
list-style-type:none;
margin:3px 15px;
padding:0px;
}
#list-subpages ul li {
margin:15px 0;
}
.page-link{
font-variant:small-caps;
font-size:14px;
font-family: Georgia, Serif;
}
#list-subpages p {
margin:4px 10px;
padding:0;
}
/* Styles needed to handle comments */
.xoxo,.children{
list-style-type:none;
margin:4px;
padding:0 0 0 10px;
}
.children{margin:1px 4px;}
#respond h3,#content h3 {

font-family: Arial, Helvetica, sans-serif;
font-size:13px;
margin: 10px 0 2px 0;
}
#commentform textarea{
width:99%;
background:#fff;
border: 1px;
background:#fff;
padding: 2px;
border-color:#cccccc;
border-style:solid;
}
#comments ul {
list-style-type:none;
list-style-position:inside;
margin:0;
padding:5px;
}
#comments li {border:1px solid #999999;}
#comments .children{padding:0 0 0 25px;}
#comments blockquote{
padding-left:10px;
margin:10px 60px;
}
#comments blockquote blockquote{margin:10px 20px;}
#comments blockquote p {
padding:0;
margin:0;
}
#comments #author-info img {
float:left;
margin-right:7px;
}
#comments #author-info {font-size:11px;}
#comments p,#comments .reply {
font-size:12px;
margin-left:42px;
}
#comments .reply {margin-bottom:10px;}
#comments .comment,
#comments .trackback,
#comments .pingback {
padding:5px;
margin:5px 0;
}
.thread-odd, .depth-1, .depth-4{background:#f2f2f2;}
.depth-2, .depth-5 {background:#fff;}
.thread-even, .depth-3, .depth-6{background:#cccccc;}
.children .alt, .children .odd {background:#E0DAE6;}
.children .even {background:#C6BDCE;}
/* Shows info about comment status */
#comments-status {
margin: 10px auto;
padding:15px 0 15px 0;
background-color:#f2f2f2;
text-align:right;
font-size:11px;
}
#comments-status a:link,#comments-status a:visited{font-weight:bold;}
#commentform #submit{
margin: 5px 0px;
border-width:1px;
background: #f2f2f2;
padding: 1px 4px;
border-color:#cccccc;
border-style:solid;
}

#author{
border: 1px solid #CCCCCC;}

#email{
border: 1px solid #CCCCCC;}

#url{
border: 1px solid #CCCCCC;}

#footer{
background-color:#f2f2f2;
text-align:right;
font-size:11px;
}
#theme-author{
padding:0;
margin:5px 0 0 0;
text-align:right;
}

.pre {
width:100;
}

a img {
border: none;
}

img{
padding:10px;
border:none;}