H1,H2 headings are to big

I have big H1, H2, H3, H4, H5, H6 Headers.
How can I reduce that with CSS or there's another way.
I know i'm a beginner and seems stupid question.

html,body,div,ul,ol,li,dl,dt,dd,h1,h2,h3,h4,h5,h6,pre,form,p,blockquote,fieldset,input,hr {margin:0; padding:0;}
h1,h2,h3,h4,h5,h6,pre,code,address,caption,cite,code,em,strong,th {font-size:1em; font-weight:normal; font-style:normal;}
fieldset,img,hr {border:none;}
caption,th {text-align:left;}
table {border-collapse:collapse; border-spacing:0;}
td {vertical-align:top;}
.html{
 background-color: #D4D4D4;
 
}
ol, ul{
 margin-left: 20px;
}
.header{
 background: #1e5799; /* Old browsers */
}
.content{
 margin:auto;
 width: 1000px;
 /*background: white;*/
 background-color: #D4D4D4;
 padding: 25px 10px 20px 20px;
 font: 67.5% 'Lucida Sans Unicode', 'Bitstream Vera Sans', 'Trebuchet Unicode MS', 'Lucida Grande', Verdana, Helvetica, sans-serif;
 border-left:thin gray solid;
 border-right:thin gray solid;
 border-bottomolid gray 1px;
 min-height: 500px;}
.footer
{
 margin:auto;
 margin-top: 50px;
}
.snelmenu{
 background:white;
 border: thin gray dashed;
 margin: 5px;
 padding: 10px;
 width: 250px;
 float: right;}
.tip{
 background:#66CCFF;
 padding:10px;
 border: thin gray dashed;
 font-size: 12px;}
 
.opgelet{
 background:#FF6666;
 padding:10px;
 border: thin gray dashed;
 font-size: 12px;}
.aandacht{
 background:#FF00FF;
 padding:10px;
 border: thin gray dashed;
 font-size: 12px;}
h1,h2,h3,h4,h5,h6 { clear:both; margin:0 0 10px; }
h1,h2 { line-height: 1.25em; }
h3,h4,h5 { line-height: 1.5em; }
h1 { font-size: 2.25em; }
h2 { font-size: 1.8em; }
h3 { font-size: 1.45em; }
h4 { font-size: 1.2em; }
h5 { font-size: 1em; }
h6 { font-size: .8em; line-height:2em;}
p {
   font-size:12px;
   font-family:Arial, Helvetica, sans-serif;
   font-weight:normal;
   font-style:normal;
   line-height:18px;
   color:black;}

My code of style.css
html body div div ul dl dt dd h1 h2 h3 h4 h5 h6 pre form p blockquote fieldset input hr {margin: 0; padding: 0;}
h1, h2, h3, h4, h5, h6, pre, code, address, caption, cite, code, em, strong, th {font-size: 1em; font-weight: normal; font-style: normal;}
fieldset, img, hr {border: none;}
caption, th {text-align: left;}
table {border-collapse: collapse; border spacing: 0;}
eg {vertical-align: top;}
.html {
background-color: # D4D4D4;
}
ol, ul {
margin-left: 20px;
}
.header {
background: # 1e5799; / * Old browsers * /
}
.content {
margin: auto;
width: 1000px;
/ * background: white; * /
background-color: # D4D4D4;
padding: 25px 10px 20px 20px;
font: 67.5% 'Lucida Sans Unicode', 'Bitstream Vera Sans', 'Trebuchet Unicode MS', 'Lucida Grande', Verdana, Helvetica, sans-serif;
border-left: thin gray solid;
border-right: thin gray solid;
border-bottom: solid gray 1px;
min-height: 500px;}
.footer
{
margin: auto;
margin-top: 50px;
}
.menu {
background: white;
border: thin gray dashed;
margin: 5px;
padding: 10px;
width: 250px;
float: right;}
.tip{
background: # 66CCFF;
padding: 10px;
border: thin gray dashed;
font size: 12px;}
.observed {
background: # FF6666;
padding: 10px;
border: thin gray dashed;
font size: 12px;}
.attention{
background: # FF00FF;
padding: 10px;
border: thin gray dashed;
font size: 12px;}
h1, h2, h3, h4, h5, h6 {clear: both; margin: 0 0 10px; }
h1, h2 {line-height: 1.25em; }
h3, h4, h5 {line-height: 1.5m; }
h1 {font-size: 2.25em; }
h2 {font-size: 1.8em; }
h3 {font-size: 1.45em; }
h4 {font-size: 1.2em; }
h5 {font-size: 1em; }
h6 {font-size: .8em; line-height: 2em;}
p {
   font size: 12px;
   font-family: Arial, Helvetica, sans-serif;
   font-weight: normal;
   font-style: normal;
   line-height: 18px;
   color: black;}

I'm still having trouble with the big ones of the h1, h2, h3, h4, h5, h6 headers
What am I doing wrong in this code?
I do not know if I can show my website to show what's wrong.
But the H1 and H2 headers seem to me to be huge
Does anyone at the top of the code see something wrong or so?
Please help.

Attached Files

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