Media Query not working...

Question

My media query for screen size of a minimum of 480 px is not working.  The Global CSS takes over.  I can't find the reason why.
It seems the brackets are in place correctly.  Can anyone see where the problem might be?  All the other queries work.
thanks
____________________  sorry, it is a long CSS file
@charset "UTF-8";
/* Simple fluid media
   Note: Fluid media requires that you remove the media's height and width attributes from the HTML
   http://www.alistapart.com/articles/fluid-images/
img, object, embed, video {
/* IE 6 does not support max-width so default to width 100% */
.ie6 img {
    width:100%;
    Dreamweaver Fluid Grid Properties
    dw-num-cols-mobile:        5;
    dw-num-cols-tablet:        9;
    dw-num-cols-desktop:    13;
    dw-gutter-percentage:    20;
    Inspiration from "Responsive Web Design" by Ethan Marcotte
    http://www.alistapart.com/articles/responsive-web-design
    and Golden Grid System by Joni Korpi
    http://goldengridsystem.com/
.fluid {
    position: relative;
.fluidList {
    list-style: none;
    list-style-image: none;
    margin-bottom: 0;
    margin-left: 0;
    margin-right: 0;
    padding-bottom: 0;
    padding-left: 0;
    padding-right: 0;
/* Mobile Layout: 480px and below. */
.gridContainer {
    margin-left: auto;
    margin-right: auto;
    width: 100%;
    padding-left: 0;
    padding-right: 0;
    clear: none;
    float: none;
#top {
    float: left;
    text-align: left;
.tagline {
    width: 100%;
    clear: both;
    margin-left: 0;
    /* [disabled]margin-top: 50px; */
    /* [disabled]top: 50px; */
    position: static;
    display: block;
    float: left;
    text-align: left;
    font-family: Impact, Haettenschweiler, "Franklin Gothic Bold", "Arial Black", sans-serif;
    font-style: italic;
#mainNav {
    width: 100%;
    float: left;
    display: block;
    background-color: #30434D;
#navMenu {
    clear: none;
    margin-left: 0;
    position: static;
    background-color: #30434D;
    font-style: normal;
    font-weight: 400;
    font-family: questrial;
    font-size: 18px;
#menuChoices {
.menuItem {
    color: #FFFFFF;
    font-family: questrial;
    font-size: 24px;
    font-weight: 400;
    padding-top: 0px;
    padding-bottom: 0px;
    width: 100%;
    clear: both;
    margin-left: 0;
    display: block;
    font-style: normal;
    height: 40px;
    line-height: 40px;
    float: left;
#SEHCMbutton a:link {
    background-color: #FC6719;
    color: #FFFFFF;
    font-family: questrial;
    font-style: normal;
    font-weight: 400;
    text-align: center;
    text-decoration: none;
#SEHCMbutton {
    float: left;
    background-color: #FC6719;
    color: #FFFFFF;
    font-family: questrial;
    font-style: normal;
    font-weight: 400;
    font-size: 18px;
    line-height: 30px;
    text-align: center;
    margin-bottom: 30px;
    display: block;
    width: 95%;
#SEHCMbutton a:visited {
    background-color: #FC6719;
    color: #FFFFFF;
    font-family: questrial;
    font-style: normal;
    font-weight: 400;
    text-align: center;
    text-decoration: none;
#SCVHpdfList {
    float: none;
.fluid.SCVHsubMenuItems a:link {
    color: #303E48;
    background-color: #CED1D3;
    display: block;
    height: 30px;
    line-height: 30px;
    text-decoration: none;
    font-family: source-sans-pro;
    font-style: normal;
    font-weight: 400;
.fluid.SCVHsubMenuItems a:hover {
    color: #FFFFFF;
    background-color: #303E48;
    display: block;
    height: 30px;
    line-height: 30px;
    text-decoration: none;
    -webkit-box-sizing: border-box;
    -moz-box-sizing: border-box;
    box-sizing: border-box;
#div2 {
    display: block;
    clear: both;
    position: relative;
    float: left;
    width: 100%;
    background-color: #FC6719;
#SubHead {
    clear: both;
    float: left;
    position: relative;
    width: 100%;
    background-repeat: repeat-x;
    background-color: #FC6719;
    text-align: center;
#mainSubHead {
    text-align: center;
    width: 100%;
    clear: none;
    margin-left: 0;
    position: static;
    color: #FFFFFF;
    font-style: normal;
    font-weight: 400;
    font-family: questrial;
    font-size: 25px;
#div3 {
width: 100%;
#div4 {
clear: both;
margin-left: 0;
width: 100%;
#mainContent {
    color: #303E48;
    font-family: source-sans-pro;
    font-style: normal;
    font-weight: 200;
    font-size: 15px;
    text-align: left;
    width: 65%;
    float: left;
    clear: both;
    padding-left: 25px;
    padding-right: 0px;
    padding-bottom: 0px;
    margin-bottom: 25px;
    margin-top: 0px;
    padding-top: 25px;
.content {
.contentStyle {
    padding-left: 30px;
    width: 85%;
    padding-right: 20px;
    margin-left: 0;
#mainAside {
    clear: none;
    position: static;
    height: auto;
    margin-left: auto;
    float: none;
    margin-right: auto;
#mainFooter {
    float: left;
    clear: both;
    background-color: #06A7E2;
    display: block;
    position: relative;
    width: 100%;
#footerLogo {
    padding-top: 15px;
    margin-left: auto;
    margin-right: auto;
    text-align: center;
#footerInfo {
    float: none;
    clear: none;
    color: #FFFFFF;
    font-style: normal;
    font-weight: 200;
    font-family: source-sans-pro;
    margin-left: auto;
    margin-right: auto;
    padding-top: 15px;
    text-align: center;
    font-size: 12px;
#asideBrochure {
    width: 100%;
    margin-left: 0;
    clear: both;
    text-align: center;
#asideVideo {
    width: 100%;
    margin-left: 0;
    text-align: center;
.lightLinks {
    color: #FFFFFF;
    font-style: normal;
    font-weight: 400;
    font-family: questrial;
    font-size: 18px;
    text-align: center;
    text-decoration: none;
.lightLinks a:link{
    color: #FFFFFF;
    font-style: normal;
    font-weight: 400;
    font-family: questrial;
    font-size: 18px;
    text-decoration: none;
.lightLinks a:hover{
    color: #3192D8;
    font-style: normal;
    font-weight: 400;
    font-family: questrial;
    font-size: 18px;
    text-decoration: none;
    text-align: center;
#thermalDiffLabel {
#thermDiffLabel {
    color: #30434D;
    font-style: normal;
    font-weight: 400;
    font-family: source-sans-pro;
    padding-top: 10px;
    padding-bottom: 0px;
    font-size: 16px;
#thermDiffPict {
#atuLabel {
    color: #30434D;
    font-style: normal;
    font-weight: 400;
    font-family: source-sans-pro;
    font-size: 16px;
    padding-top: 10px;
#atuPict {
#digitalLabel {
    color: #30434D;
    font-style: normal;
    font-weight: 400;
    font-family: source-sans-pro;
    font-size: 16px;
    padding-top: 10px;
#digitalPict {
#navChoices {
#navList {
    float: left;
    clear: both;
#PAnav {
    background-color: #30434D;
    width: 100%;
    display: block;
    clear: none;
#PAchoices {
#PAList {
    float: left;
    background-color: #30434D;
    color: #FFFFFF;
    font-style: normal;
    font-weight: 400;
    font-family: questrial;
    font-size: 18px;
    text-align: center;
    position: relative;
    width: 100%;
.PAmenuItem {
    display: block;
    height: 35px;
    line-height: 35px;
    letter-spacing: 0.3px;
.PAmenuItem a:link {
    display: block;
    height: 35px;
    line-height: 35px;
    color: #FFFFFF;
    text-decoration: none;
.PAmenuItem a:visited {
    display: block;
    height: 35px;
    line-height: 35px;
    color: #FFFFFF;
    text-decoration: none;
.PAmenuItem a:hover {
    display: block;
    height: 35px;
    line-height: 35px;
    color: #FFFFFF;
    text-decoration: none;
    background-color: #06A7E2;
.PAmenuItem a:active {
    display: block;
    height: 35px;
    line-height: 35px;
    color: #FFFFFF;
    text-decoration: none;
    background-color: #06A7E2;
.SubPageContentArea {
    color: #FFFFFF;
    font-family: source-sans-pro;
    font-style: normal;
    font-weight: 200;
    font-size: 14px;
    text-align: left;
    letter-spacing: 0.06em;
#topContent {
    width: 100%;
    color: #30434D;
    font-style: normal;
    font-weight: 200;
    font-family: source-sans-pro;
    font-size: 14px;
#pageContent {
    width: 100%;
    display: block;
    clear: both;
#asideNavArea {
    color: #FCFDFF;
    width: 30%;
    float: left;
    clear: right;
    padding-left: 15px;
    margin-left: 5px;
    margin-top: 25px;
    margin-bottom: 15px;
    background-color: #CED1D3;
#bottomContentArea {
    background-image: url(/images/grayTexture2.png);
    background-repeat: repeat;
    width: 100%;
    display: block;
    clear: both;
.bottomContent {
    color: #FFFFFF;
    font-family: source-sans-pro;
    font-style: normal;
    font-weight: 200;
    font-size: medium;
    padding-left: 15px;
    display: block;
#aboutPict {
#sectionPict {
    width: 100%;
#sideNavHolder {
    width: 200px;
    height: 300px;
    background-color: #B6C4CE;
    -webkit-box-shadow: 3px 3px 5px #303E48;
    box-shadow: 3px 3px 5px #303E48;
#bottomContentText {
#sectionPict img {
    width: 100%;
#greenMemLog img {
#indexContentArea {
    float: left;
    width: 100%;
    display: block;
#asideArea {
    width: 100%;
    float: left;
    background-color: #CED1D3;
    height: 200px;
    clear: both;
#mainAnim {
    width: 100%;
    display: block;
    float: left;
    clear: both;
    height: 200px;
    margin-bottom: 15px;
#slideShow {
    width: 100%;
#bottomContent {
    clear: none;
    background-image: url(images/grayTexture2.png);
    background-repeat: repeat;
    display: block;
    width: 100%;
    padding-top: 25px;
    padding-bottom: 25px;
    float: left;
#sectionPhoto {
#sectionPhoto img {
    width: 100%;
    display: block;
    clear: both;
#bottomContent2 {
    width: 250px;
    display: block;
    float: left;
    clear: left;
    margin-left: auto;
    margin-right: auto;
#bottomContent1 {
    width: 90%;
    clear: none;
#sectionVideo {
    width: 95%;
    float: left;
    margin-left: 15px;
    text-align: left;
    margin-top: 15px;
    display: block;
#sectionVideo img  {
    display: block;
    float: left;
    width: 100%;
#Thermalnav  {
    width: 0px;
.Thermalmenuitem {
    display: block;
    background-color: #06A7E2;
    color: #FFFFFF;
    font-family: questrial;
    font-style: normal;
    font-weight: 400;
    text-decoration: none;
    height: 30px;
    padding-left: 15px;
    border-color: #FFFFFF;
    border-bottom-width: thin;
    border-bottom-style: dotted;
.Thermalmenuitem a:hover {
    display: block;
    background-color: #FC6719;
    color: #FFFFFF;
    font-family: questrial;
    font-style: normal;
    font-weight: 400;
    text-decoration: none;
    height: 30px;
    padding-left: 15px;
.Thermalmenuitem a:link {
    display: block;
    color: #FFFFFF;
    font-family: questrial;
    font-style: normal;
    font-weight: 400;
    text-decoration: none;
    height: 30px;
    padding-left: 15px;
.Thermalmenuitem a:visited {
    display: block;
    color: #FFFFFF;
    font-family: questrial;
    font-style: normal;
    font-weight: 400;
    text-decoration: none;
    height: 30px;
    padding-left: 15px;
.Thermalmenuitem a:active {
    display: block;
    color: #FFFFFF;
    font-family: questrial;
    font-style: normal;
    font-weight: 400;
    text-decoration: none;
    height: 30px;
    padding-left: 15px;
    background-color: #303E48;
#ThermalList {
#thermalLinks {
    margin-top: 15px;
    display: block;
    width: 400px;
    margin-left: auto;
    margin-right: auto;
#ThermalLinks {
    display: block;
    margin-top: 20px;
    clear: both;
    text-align: center;
    margin-bottom: 20px;
    float: left;
    width: 100%;
#SquareIcon {
    clear: both;
    width: 125px;
    float: left;
#LinearIcon {
    width: 140px;
    clear: none;
    float: left;
    margin-left: 20px;
#mainParagraph {
    color: #303E48;
    font-family: source-sans-pro;
    font-style: normal;
    font-weight: 200;
    text-align: left;
    float: left;
    clear: both;
    width: 98%;
    margin-top: 15px;
    margin-bottom: 20px;
#leftSpacer {
    width: 10%;
    height: 500px;
    display: block;
    float: left;
#ThermalVideo {
    float: left;
    width: 100%;
    border: thin solid #000000;
#ThermalChoose {
    text-align: left;
    background-color: #FC6719;
    color: #FDFDFD;
    display: block;
    height: 35px;
    line-height: 35px;
    font-family: questrial;
    font-style: normal;
    font-weight: 400;
    width: 100%;
    float: left;
    padding-left: 10px;
#SquareDiffuserSection {
    width: 100%;
    background-color: #06A7E2;
    color: #FFFFFF;
    font-family: questrial;
    font-style: normal;
    font-weight: 400;
    font-size: 22px;
    text-align: left;
    display: block;
    height: 35px;
    float: left;
#SquareDiffText {
    float: left;
    width: 90%;
    margin-left: 15px;
    margin-top: 20px;
    color: #303E48;
    font-family: source-sans-pro;
    font-style: normal;
    font-weight: 200;
    margin-bottom: 25px;
    text-align: left;
#squareDiffuserPicts {
    width: 100%;
    clear: both;
#SCVH {
    float: none;
    width: 150px;
    margin-left: auto;
    margin-right: auto;
    clear: none;
    display: block;
.Labels   {
    color: #06A7E2;
    font-family: questrial;
    font-style: normal;
    font-weight: 400;
    text-align: center;
    vertical-align: bottom;
#SCAH   {
    float: none;
    clear: none;
    display: block;
    width: 150px;
    margin-left: auto;
    margin-right: auto;
#brochureThumb   {
    visibility: hidden;
#SquareDiffSectTitle   {
    color: #FFFFFF;
    font-family: questrial;
    font-style: normal;
    font-weight: 400;
    padding-left: 15px;
#SquarePict   {
    clear: left;
    width: 250px;
    margin-left: auto;
    margin-right: auto;
    margin-bottom: 10px;
#brochureLink   {
    visibility: hidden;
#bottomContent3   {
    float: left;
    width: 90%;
.zeroMargin_mobile   {
margin-left: 0;
.hide_mobile   {
display: none;
#SCAHbutton {
    float: left;
    width: 100%;
    clear: both;
    margin-bottom: 10px;
#SCVHbutton {
    float: left;
    clear: both;
    width: 100%;
    margin-bottom: 10px;
#SCbutton {
    float: left;
    clear: both;
    width: 100%;
    margin-bottom: 10px;
#SCVHbuttText {
    color: #303E48;
    font-family: source-sans-pro;
    font-style: normal;
    font-weight: 200;
    width: 90%;
    clear: left;
    float: left;
    margin-left: 10px;
    text-align: center;
#SCbuttText {
    position: relative;
    color: #303E48;
    font-family: source-sans-pro;
    font-style: normal;
    font-weight: 200;
    width: 90%;
    float: left;
    clear: left;
    margin-left: 15px;
    text-align: center;
#SC {
    width: 150px;
    margin-left: auto;
    margin-right: auto;
    float: none;
    clear: none;
    display: block;
#SCAHbuttText {
    width: 90%;
    float: left;
    clear: left;
    margin-left: 15px;
    color: #303E48;
    font-family: source-sans-pro;
    font-style: normal;
    font-weight: 200;
    text-align: center;
#sqDiffPict {
    width: 150px;
    margin-top: 20px;
#LAD {
    width: 150px;
    margin-left: auto;
    margin-right: auto;
    float: none;
    display: block;
#LADbuttonText {
    float: left;
    clear: left;
    width: 90%;
    text-align: center;
#VAC {
    width: 150px;
    margin-left: auto;
    margin-right: auto;
    float: none;
    display: block;
#VACbuttonText {
    float: left;
    clear: left;
    width: 95%;
    text-align: center;
#VACH {
    width: 150px;
    margin-left: auto;
    margin-right: auto;
    float: none;
    display: block;
#VACHbuttonText {
    float: left;
    clear: left;
    width: 95%;
    text-align: center;
#LADbutton   {
    width: 100%;
#VACbutton {
    width: 100%;
    float: left;
    clear: left;
#VACHbutton {
    float: left;
    clear: left;
    width: 100%;
#LinearDiffusers {
    color: #FC6719;
    font-family: questrial;
    font-style: normal;
    font-weight: 400;
    font-size: 22px;
    margin-bottom: 12px;
    padding-left: 15px;
#LinearDiffPict {
    margin-left: 5px;
    float: right;
    width: 45%;
#SquareDiffPict {
    float: right;
    color: #06A7E2;
    width: 40%;
#SquareDiffPict img {
    width: 170px;
#LinearDiffPict img {
    width: 175px;
#PHseries {
    width: 200px;
    float: left;
    clear: none;
    margin-bottom: 15px;
    margin-top: 20px;
    margin-left: auto;
    margin-right: auto;
#AirTerminalPicts {
    float: left;
    clear: both;
    background-color: #E6EBEE;
    display: block;
    width: 100%;
#PTseries {
    width: 200px;
    float: left;
    clear: left;
    margin-right: auto;
    margin-bottom: 25px;
    margin-top: 20px;
    margin-left: auto;
#ATUpicts {
    text-align: center;
    padding-left: 10px;
    margin-bottom: 20px;
#PHbuttonText {
    color: #303E48;
    font-family: source-sans-pro;
    font-style: normal;
    font-weight: 200;
    text-align: left;
    padding-left: 12px;
#PTbuttonText {
    color: #303E48;
    font-family: source-sans-pro;
    font-style: normal;
    font-weight: 200;
    padding-left: 12px;
    text-align: left;
#ModelPhSeries {
    padding-left: 5%;
    color: #FC6719;
    font-family: questrial;
    font-style: normal;
    font-weight: 400;
    font-size: 22px;
#ATUVideo {
    width: 95%;
    margin-bottom: 20px;
    float: left;
    display: block;
    clear: both;
#mainParagraphATU {
    float: none;
    width: 95%;
    padding-bottom: 15px;
    color: #303E48;
    font-family: source-sans-pro;
    font-style: normal;
    font-weight: 200;
#ATUsectionVideo {
    margin-top: 35px;
    margin-left: 10px;
    width: 100%;
    float: left;
#mainParagraphPH {
    color: #303E48;
    font-family: source-sans-pro;
    font-style: normal;
    font-weight: 200;
    margin-bottom: 15px;
#PHatuSeries {
    float: right;
#ATUSectTitle {
    padding-left: 10px;
    width: 95%;
    color: #FFFFFF;
    font-family: questrial;
    font-style: normal;
    font-weight: 400;
    font-size: 22px;
    line-height: 30px;
#ATUplace {
    width: 100%;
#ATUSection {
    float: left;
    width: 100%;
    background-color: #06A7E2;
#PHDuct {
    margin-top: 35px;
    float: left;
    display: block;
    width: 100%;
#PHductSection {
    float: left;
    background-color: #E6EBEE;
    clear: left;
    width: 100%;
#PHductCaption {
    float: left;
    clear: left;
    color: #FFFFFF;
    font-family: source-sans-pro;
    font-style: normal;
    font-weight: 400;
    font-size: 22px;
    width: 100%;
    background-color: #303E48;
    line-height: 50px;
#PHaccessText {
    margin-top: 20px;
    float: left;
    width: 100%;
#PHdownloadTitle {
    background-color: #FC6719;
    color: #FFFFFF;
    font-family: questrial;
    font-style: normal;
    font-weight: 400;
    line-height: 35px;
    font-size: 18px;
#PHpdfList {
    color: #303E48;
    font-family: source-sans-pro;
    font-style: normal;
    font-weight: 400;
    line-height: 50px;
#PHdownloads {
    float: left;
    clear: right;
    width: 100%;
    margin-top: 35px;
    margin-bottom: 20px;
#Ductpict {
    float: left;
    display: block;
    width: 100%;
.PHdata a:active {
    color: #06A7E2;
    text-decoration: none;
#PHaccessories {
    float: left;
.PHdata a:visited {
    color: #303E48;
    text-decoration: none;
.PHdata a:hover {
    color: #06A7E2;
    text-decoration: none;
.PHdata a:link {
    color: #303E48;
    text-decoration: none;
.PHdata {
    border-bottom: 6px solid #E6EBEE;
    background-color: #FFFFFF;
#PHimage {
    width: 150px;
#PTseries2 {
    float: right;
#Ductpict2 {
    width: 510px;
    float: left;
#PHductCaption2 {
    width: 510px;
    float: left;
    background-color: #303E48;
    height: 40px;
    color: #FFFFFF;
    font-family: questrial;
    font-style: normal;
    font-weight: 400;
    line-height: 40px;
    font-size: 22px;
#DigitalContent {
    text-align: left;
    margin-top: 20px;
    background-color: #E6EBEE;
    float: left;
    width: 90%;
#digiPicts {
    background-color: #E6EBEE;
    display: block;
    clear: left;
    width: 300px;
#SEHCMbutton a:hover {
    background-color: #06A7E2;
    color: #FFFFFF;
    font-family: questrial;
    font-style: normal;
    font-weight: 400;
    text-align: center;
    display: block;
#EdgeSVCH {
    float: left;
    margin-left: 10px;
#SCVHanim   {
    float: left;
    margin-top: 35px;
    width: 95%;
    margin-bottom: 10px;
#SVCHanimPict {
    float: left;
    width: 100%;
#SCVHhowToButt {
    float: left;
.fluid.SCVHsubMenuItems {
    color: #303E48;
    background-color: #CED1D3;
    display: block;
    width: 100%;
    text-align: center;
    height: 30px;
    line-height: 30px;
    font-family: source-sans-pro;
    font-style: normal;
    font-weight: 200;
#SCVHsub {
    margin-bottom: 10px;
.fluid.SCVHsubMenuItems2  {
    background-color: #CED1D3;
    color: #303E48;
    font-family: source-sans-pro;
    font-style: normal;
    font-weight: 400;
    text-align: center;
    height: 30px;
    display: block;
.fluid.SCVHsubMenuItems2 a:link  {
    color: #303E48;
    font-family: source-sans-pro;
    font-style: normal;
    font-weight: 400;
    text-decoration: none;
    line-height: 30px;
    display: block;
.fluid.SCVHsubMenuItems2 a:hover  {
    background-color: #303E48;
    font-family: source-sans-pro;
    font-style: normal;
    font-weight: 400;
    text-decoration: none;
    line-height: 30px;
    display: block;
    color: #FFFFFF;
.fluid.SCVHsubMenuItems2 a:visited  {
    background-color: #CED1D3;
    font-family: source-sans-pro;
    font-style: normal;
    font-weight: 400;
    text-decoration: none;
    line-height: 30px;
    display: block;
    color: #303E48;
.SCVHlist a:link {
    color: #303E48;
    text-decoration: none;
    display: block;
    background-color: #FFFFFF;
    height: 30px;
    line-height: 30px;
    font-family: source-sans-pro;
    font-style: normal;
    font-weight: 400;
    font-size: 16px;
    border-bottom: medium solid #E6EBEE;
.SCVHlist a:hover {
    color: #FFFFFF;
    background-color: #06A7E2;
    display: block;
.SCVHlist a:visited {
    color: #303E48;
    background-color: #FFFFFF;
    display: block;
#SCVHchartPict {
    float: left;
    text-align: center;
    width: 300px;
#SCVHdata {
    margin-top: 25px;
    text-align: left;
    width: 90%;
    float: left;
#SCVHbottomData {
    margin-top: 15px;
    width: 300px;
    float: left;
#SCVHchartPict img {
#SCVHchartGraphic {
    width: 100%;
#SCVHdimGraphic {
    width: 100%;
#SCVHdimenPict {
    margin-top: 20px;
    width: 300px;
#SCVHvideo {
    width: 95%;
#LADimages {
    float: right;
    width: 200px;
    margin-left: 20px;
#LAD3D {
    float: right;
#LADusePict {
    float: right;
    clear: right;
    margin-top: 50px;
#MidContent {
    float: left;
    text-align: left;
    margin-top: 20px;
#CoAnda {
    margin-top: 25px;
    border: thin solid #FFFFFF;
    float: left;
    width: 300px;
    padding-left: 15px;
#VACinduction {
    float: right;
    margin-left: 10px;
#PAproducts {
    width: 100%;
    clear: both;
    display: block;
    float: left;
#SlideShow {
    width: 100%;
    float: left;
    height: 400px;
    display: block;
#ProductWrapper {
    width: 300px;
    display: block;
    clear: both;
    float: left;
.fluid.PromoBlocks {
    width: 225px;
    display: block;
    clear: both;
#SQdiffPict {
    width: 100%;
#ATUpict {
    width: 100%;
#DigiDiffPict {
    width: 100%;
@media only screen and (min-width:480px){
#PAproducts {
    width: 100%;
    clear: both;
    display: block;
    float: left;
#mainAnim {
    width: 100%;
    display: block;
    float: left;
    clear: both;
    height: 270px;
    margin-bottom: 15px;
/* Tablet Layout: 481px to 768px. Inherits styles from: Mobile Layout. */
@media only screen and (min-width: 600px) {
.fluid.SCVHsubMenuItems2 a:link  {
    color: #303E48;
    font-family: source-sans-pro;
    font-style: normal;
    font-weight: 400;
    text-decoration: none;
    line-height: 30px;
    display: block;
.fluid.SCVHsubMenuItems2 a:hover  {
    background-color: #303E48;
    font-family: source-sans-pro;
    font-style: normal;
    font-weight: 400;
    text-decoration: none;
    line-height: 30px;
    display: block;
    color: #FFFFFF;
.fluid.SCVHsubMenuItems2  {
    background-color: #CED1D3;
    color: #303E48;
    font-family: source-sans-pro;
    font-style: normal;
    font-weight: 400;
    text-align: left;
    height: 30px;
    display: block;
    padding-left: 10px;
    font-size: 13px;
    width: 240px;
    float: left;
    clear: right;
#DigitalPicts {
    float: left;
    display: block;
#SEHCMbutton {
    float: left;
    margin-left: 15px;
    background-color: #FC6719;
    color: #FFFFFF;
    font-family: questrial;
    font-style: normal;
    font-weight: 400;
    font-size: 18px;
    line-height: 40px;
    text-align: center;
    display: block;
    width: 62%;
.gridContainer {
    width: 100%;
    padding-left: 0%;
     padding-right: 0%;
    clear: none;
    float: none;
    margin-left: auto;
#top {
    text-align: left;
    float: left;
.tagline {
width: 100%;
clear: both;
margin-left: 0;
#menuChoices {
#div2 {
    width: 100%;
    background-color: #FC6719;
    height: 380px;
#SubHead {
    position: static;
    height: 40px;
    width: 100%;
#mainSubHead {
    clear: both;
    margin-left: 0;
    position: static;
    height: 40px;
    width: 100%;
    line-height: 40px;
#div3 {
width: 100%;
#div4 {
clear: both;
margin-left: 0;
width: 100%;
#mainContent {
.content {
.contentStyle {
    width: 88.6792%;
    margin-left: 0;
#mainAside {
    margin-left: auto;
    position: static;
    height: auto;
    display: block;
    width: 700px;
    margin-right: auto;
#mainFooter {
#footerLogo {
    margin-left: 25px;
    text-align: left;
#footerInfo {
    margin-left: 25px;
    text-align: left;
    width: 400px;
#asideBrochure {
    clear: both;
    float: left;
#asideVideo {
    margin-left: 0;
    float: left;
    text-align: center;
.lightLinks {
    text-align: center;
    line-height: 16px;
#thermalDiffLabel {
#thermDiffLabel {
    width: 330px;
    padding-top: 10px;
    padding-right: 10px;
    padding-bottom: 10px;
    padding-left: 10px;
#thermDiffPict {
#atuLabel {
    padding-top: 10px;
    padding-right: 10px;
    padding-bottom: 10px;
    padding-left: 10px;
    width: 330px;
#atuPict {
#digitalLabel {
    width: 330px;
    padding-top: 10px;
    padding-right: 10px;
    padding-bottom: 10px;
    padding-left: 10px;
#digitalPict {
.mainSubHead {
    color: #FFFFFF;
    background-color: #F60;
    display: block;
    font-family: questrial;
    font-size: 30px;
    margin: auto;
    height: 80px;
    line-height: 40px;
    font-style: normal;
    font-weight: 400;
#navList {
#PAnav {
#PAchoices {
#PAList {
    position: relative;
    margin-left: auto;
    margin-right: auto;
.PAmenuItem {
    float: left;
    position: relative;
    display: block;
    width: 115px;
    clear: right;
    font-size: 13px;
    padding-left: 10px;
.SubPageContentArea {
    padding-bottom: 20px;
    text-align: left;
#topContent {
#pageContent {
    width: 100%;
#asideNavArea {
#bottomContentArea {
.bottomContent {
#aboutPict {
#sectionPict {
#sideNavHolder {
#bottomContentText {
#indexContentArea {
#asideArea {
    line-height: 30px;
    width: 150px;
    height: 700px;
    float: left;
    clear: none;
#mainAnim {
    height: 425px;
    width: 100%;
    float: left;
#bottomContent {
#sectionPhoto {
#bottomContent2 {
    float: left;
    clear: left;
    width: 250px;
    margin-left: auto;
    margin-right: auto;
#bottomContent1 {
    float: left;
    width: 575px;
    margin-left: 5px;
#sectionVideo {
    width: 580px;
    float: left;
    margin-left: 15px;
.mainParagraphs {
    color: #303E48;
    font-family: source-sans-pro;
    font-style: normal;
    font-weight: 200;
    font-size: 15px;
    text-align: left;
#ThermalList {
#thermalLinks {
#ThermalLinks {
    float: left;
    clear: both;
    width: 150px;
    margin-bottom: 10px;
#SquareIcon {
    width: 100px;
    margin-left: auto;
    margin-right: auto;
    margin-top: 15px;
    float: none;
#LinearIcon {
    float: none;
    width: 120px;
    margin-left: auto;
    margin-right: auto;
    margin-top: 15px;
    clear: left;
#mainParagraph {
    float: left;
    clear: both;
    width: 98%;
    margin-top: 0px;
#leftSpacer {
#ThermalVideo {
    width: 70%;
    margin-top: 20px;
    margin-left: 15px;
    border-width: thin;
#ThermalChoose {
    margin-top: 0px;
    text-align: center;
    line-height: 1.5em;
    height: 50px;
#SquareDiffuserSection {
    height: 35px;
#SquareDiffText {
    width: 575px;
    margin-top: 20px;
    margin-bottom: 25px;
    margin-left: 15px;
    padding-left: 8px;
    text-align: left;
#squareDiffuserPicts {
    width: 600px;
    margin-top: 15px;
    margin-left: 15px;
#SCVH {
    display: block;
    width: 150px;
    float: none;
    margin-left: 0px;
    margin-right: 0px;
#SCVHanim   {
    float: left;
    margin-top: 35px;
    width: 50%;
.fluid.SCVHsubMenuItems {
    color: #303E48;
    background-color: #CED1D3;
    display: block;
    height: 30px;
    line-height: 30px;
    width: 220px;
    font-size: 14px;
    text-align: left;
    padding-left: 10px;
    float: left;
    clear: right;
    -webkit-box-sizing: border-box;
    -moz-box-sizing: border-box;
    box-sizing: border-box;
#SCVHdimGraphic {
    width: 600px;
#SCVHdimenPict {
    margin-top: 20px;
#SCAH {
    display: block;
    width: 150px;
    margin-left: 0px;
    margin-right: 0px;
#SCbutton {
    float: left;
    width: 175px;
    clear: right;
    position: relative;
    margin-left: 25px;
#PHDuct {
    margin-top: 35px;
    float: left;
    display: block;
#PHductCaption2 {
    width: 510px;
    float: left;
    background-color: #303E48;
    height: 40px;
    color: #FFFFFF;
    font-family: questrial;
    font-style: normal;
    font-weight: 400;
    line-height: 40px;
    font-size: 22px;
#brochureThumb {
    visibility: visible;
#SquareDiffSectTitle {
    width: 500px;
    height: 35px;
    text-align: left;
    color: #FFFFFF;
    margin-left: 20px;
    line-height: 35px;
#SquarePict {
    width: 225px;
    margin-bottom: 10px;
    margin-left: auto;
    margin-right: auto;
    clear: left;
#LADbutton   {
    width: 175px;
    float: left;
#brochureLink {
    visibility: visible;
#bottomContent3 {
    width: 595px;
    float: left;
    clear: left;
    margin-left: 15px;
.hide_tablet {
display: none;
.zeroMargin_tablet {
margin-left: 0;
#SCVHbutton {
    float: left;
    width: 175px;
#SCVHbuttText {
    color: #303E48;
    font-family: source-sans-pro;
    font-style: normal;
    font-weight: 200;
    width: 90%;
    float: left;
    clear: right;
    text-align: left;
#SCAHbuttText {
    float: left;
    clear: right;
    width: 90%;
    color: #303E48;
    font-family: source-sans-pro;
    font-style: normal;
    font-weight: 200;
    position: relative;
    text-align: left;
#SCbuttText {
    position: relative;
    color: #303E48;
    font-family: source-sans-pro;
    font-style: normal;
    font-weight: 200;
    width: 90%;
    float: left;
    clear: none;
    display: block;
    text-align: left;
#SC {
    width: 150px;
    float: none;
    margin-left: 0px;
    margin-right: 0px;
#SCAHbutton {
    float: left;
    width: 175px;
    clear: right;
    position: relative;
    margin-left: 25px;
    margin-bottom: 20px;
#sqDiffPict {
    width: 190px;
    margin-top: 20px;
#LinearDiffusers {
    color: #FC6719;
    font-family: questrial;
    font-style: normal;
    font-weight: 400;
    font-size: 22px;
    padding-left: 15px;
    margin-bottom: 12px;
    float: left;
    width: 100%;
#VACbutton {
    width: 175px;
    float: left;
    clear: right;
    margin-left: 25px;
#VACHbutton {
    float: left;
    width: 175px;
    clear: right;
    margin-left: 25px;
#VACbuttonText {
    float: left;
    clear: left;
    width: 90%;
    padding-left: 10px;
    text-align: left;
#LADbuttonText {
    float: left;
    clear: left;
    width: 90%;
    padding-left: 10px;
    text-align: left;
#VACHbuttonText {
    float: left;
    clear: left;
    width: 90%;
    padding-left: 10px;
    text-align: left;
#LAD {
    width: 150px;
    margin-left: 0px;
#VAC {
    width: 150px;
    margin-left: 0px;
#VACH {
    width: 150px;
    margin-left: 0px;
#linearPict {
    float: left;
    clear: right;
    margin-left: 0px;
#linearPict img {
    width: 150px;
    display: block;
#SquareDiffPict {
    color: #06A7E2;
    float: right;
    text-align: center;
    width: 25%;
#LinearDiffPict {
    margin-left: 5px;
    float: right;
    width: 25%;
#ATUsectionVideo {
    margin-top: 35px;
    width: 95%;
    float: left;
    margin-left: 40px;
#ATUVideo {
    width: 62%;
    margin-bottom: 20px;
    float: left;
    clear: right;
    margin-left: 15px;
#mainParagraphATU {
    float: left;
    width: 200px;
#PHseries {
    width: 200px;
    float: left;
    margin-left: 10%;
    clear: none;
    margin-bottom: 25px;
    margin-top: 20px;
#PHductCaption {
    float: left;
    clear: left;
    color: #FFFFFF;
    font-family: source-sans-pro;
    font-style: normal;
    font-weight: 400;
    font-size: 22px;
    width: 100%;
    background-color: #303E48;
    line-height: 50px;
#PHdownloads {
    float: left;
    clear: right;
    width: 250px;
    margin-left: 30px;
    margin-top: 35px;
#PHatuSeries {
    float: right;
#PHimage {
    width: 225px;
#PHaccessText {
    margin-top: 20px;
#ATUSectTitle {
    padding-left: 40px;
#PTseries2 {
    float: right;
#PTseries {
    width: 200px;
    float: left;
    clear: right;
    margin-right: auto;
    margin-bottom: 25px;
    margin-top: 20px;
    margin-left: 35px;
#digiPicts {
    float: right;
    background-color: #E6EBEE;
#DigitalContent {
    text-align: left;
    margin-top: 20px;
    background-color: #E6EBEE;
    margin-left: 30px;
#Ductpict {
    width: 511px;
    float: left;
    display: block;
    clear: right;
#Ductpict2 {
    width: 510px;
    float: left;
#DigitalPicts {
    float: right;
#SCVHsub {
    width: 100%;
    margin-bottom: 15px;
#EdgeSVCH {
    float: right;
    margin-left: 20px;
#SVCHanimPict {
    float: left;
    width: 100%;
#SCVHchartPict {
    float: right;
    margin-left: 20px;
    width: 350px;
#SCVHbottomData {
    margin-top: 15px;
    width: 600px;
    float: left;
    clear: both;
#SCVHvideo {
    width: 100%;
#CoAnda {
    margin-top: 25px;
    border: thin solid #FFFFFF;
    float: left;
    width: 500px;
    padding-left: 15px;
#SlideShow {
    width: 100%;
    height: 455px;
    float: left;
#ProductWrapper {
    width: 600px;
    margin-left: auto;
    margin-right: auto;
    display: block;
.fluid.PromoBlocks {
    width: 180px;
    float: left;
    margin-top: 20px;
    margin-left: 15px;
    clear: none;
    display: block;
#SQdiffPict {
    display: block;
#ATUpict {
    display: block;
#DigiDiffPict {
    width: 100%;
    display: block;
/* additional media query of min 600px*/
/* Desktop Layout: 769px to a max of 1232px.  Inherits styles from: Mobile Layout and Tablet Layout. */
@media only screen and (min-width:800px){
.gridContainer {
    width: 100%;
    max-width: 1920px;
    padding-left: 0;
    padding-right: 0;
    margin: auto;
    clear: none;
    float: none;
    margin-left: auto;
#top {
    float: left;
.tagline {
width: 79.3103%;
margin-left: 1.2987%;
clear: none;
#mainNav {
.menuItem {
    clear: none;
    background-size: auto 40px;
    padding-bottom: 0px;
    padding-right: 0px;
    padding-top: 0px;
#top img {
    text-align: left;
    background-repeat: no-repeat;
    float: left;
    margin-left: 10px;
#SEHCMbutton {
    float: left;
    margin-left: 35px;
    background-color: #FC6719;
    color: #FFFFFF;
    font-family: questrial;
    font-style: normal;
    font-weight: 400;
    font-size: 18px;
    height: 40px;
    line-height: 40px;
    text-align: center;
    display: block;
    width: 62%;
#div2 {
    text-align: center;
    width: 100%;
    background-color: #FC6719;
    background-repeat: repeat-x;
    clear: both;
#SlideShow {
    width: 100%;
    height: 555px;
    float: left;
#SubHead {
    position: static;
    margin-left: auto;
    height: 45px;
    width: 100%;
    top: 586px;
    left: 0px;
    background-color: #FC6719;
#mainSubHead {
    margin-left: 0;
    clear: both;
    position: static;
    height: 45px;
    width: 100%;
    #SCVHsub {
    width: 100%;
    margin-bottom: 15px;
.fluid.SCVHsubMenuItems {
    color: #303E48;
    background-color: #CED1D3;
    display: block;
    height: 30px;
    line-height: 30px;
    font-size: 15px;
    text-align: left;
    padding-left: 15px;
    width: 250px;
    #SCVHlist a:link {
    color: #303E48;
    font-family: source-sans-pro;
    font-style: normal;
    font-weight: 400;
    font-size: 16px;
    text-decoration: none;
#SCVHpdfList {
    float: none;
    color: #303E48;
    font-family: source-sans-pro;
    font-style: normal;
    font-weight: 400;
#SCVHlist {
    height: 25px;
    color: #303E48;
    font-family: source-sans-pro;
    font-style: normal;
    font-weight: 400;
    font-size: 16px;
    background-color: #FFFFFF;
    border-bottom-style: solid;
    border-bottom-color: #E6EBEE;
#SCVHanim   {
    float: left;
    margin-top: 35px;
    width: 511px;
#SCVHdimGraphic {
    float: right;
#SCVHdimenPict {
    margin-top: 20px;
    width: 800px;
    float: right;
#div3 {
width: 100%;
#div4 {
margin-left: 1.2987%;
clear: none;
width: 29.8701%;
#mainContent {
.content {
.contentStyle {
    width: 55%;
    margin-left: 0;
    float: left;
#mainAside {
    position: relative;
    width: 325px;
    float: left;
    clear: right;
    display: block;
    margin-left: 30px;
#mainFooter {
#footerLogo {
    margin-left: 25px;
#footerInfo {
    line-height: 30px;
    display: block;
    height: 30px;
    float: none;
    clear: none;
    text-align: left;
    width: 400px;
#asideBrochure {
    width: 325px;
    margin-left: 0;
    clear: none;
    float: left;
#asideVideo {
    width: 325px;
    margin-left: 0;
    float: left;
.mainSubHead {
    color: #FFFFFF;
    background-color: #F60;
    display: block;
    font-family: questrial;
    font-size: 30px;
    margin: auto;
    height: 40px;
    line-height: 40px;
    font-style: normal;
    font-weight: 400;
.lightLinks {
#thermalDiffLabel {
#thermDiffLabel {
    width: 280px;
    padding-top: 10px;
    padding-right: 10px;
    padding-bottom: 10px;
    padding-left: 10px;
#thermDiffPict {
#atuLabel {
    padding-top: 10px;
    /* [disabled]padding-right: 10px; */
    padding-bottom: 10px;
    padding-left: 10px;
    width: 280px;
#atuPict {
#digitalLabel {
    padding-top: 10px;
    padding-right: 10px;
    padding-bottom: 10px;
    padding-left: 10px;
    width: 280px;
#digitalPict {
    padding-bottom: 2px;
#navChoices {
#navList {
#PAnav {
    background-color: #30434D;
    display: block;
#PAchoices {
#PAList {
    display: block;
    margin-left: auto;
    margin-right: auto;
    float: left;
.PAmenuItem {
    padding-left: 10px;
    width: 150px;
    font-size: 15px;
.mainSubHead {
    color: #FFFFFF;
    display: block;
    font-family: questrial;
    font-size: 30px;
    margin: auto;
    font-style: normal;
    font-weight: 400;
#AboutUsText {
    padding-left: 15px;
    width: 92%;
#pageContent {
#asideNavArea {
#bottomContentArea {
.bottomContent {
#aboutPict {
#sectionPict {
#sideNavHolder {
#bottomContentText {
#indexContentArea {
#asideArea {
    height: 725px;
    width: 275px;
    float: left;
    clear: right;
    padding-bottom: 25px;
#mainAnim {
    width: 100%;
    display: block;
    height: 555px;
    float: left;
#bottomContent {
#sectionPhoto {
#bottomContent1 {
    float: left;
    width: 800px;
    margin-left: 15px;
#bottomContent2 {
    clear: right;
    margin-left: 20px;
    float: left;
#sectionVideo {
    margin-left: 5%;
    width: 800px;
#ThermalList {
#thermalLinks {
#ThermalLinks {
    width: 200px;
    text-align: center;
#SquareIcon {
    margin-left: auto;
    margin-right: auto;
    width: 125px;
    display: block;
    float: none;
#LinearIcon {
    margin-left: auto;
    margin-right: auto;
    display: block;
    width: 145px;
    float: none;
    clear: both;
#mainParagraph {
    color: #303E48;
    font-family: source-sans-pro;
    font-style: normal;
    font-weight: 200;
    text-align: left;
    float: none;
    clear: both;
    width: 754px;
    margin-top: 10px;
    margin-bottom: 40px;
#leftSpacer {
#ThermalVideo {
    display: block;
    float: left;
    clear: right;
    margin-top: 20px;
    width: 534px;
    margin-left: 30px;
    margin-right: auto;
#ThermalChoose {
#SquareDiffuserSection {
    display: block;
    float: left;
    clear: both;
    width: 100%;
    padding-left: 5%;
    height: 35px;
#SquareDiffText {
    width: 750px;
    float: left;
    margin-left: 5%;
    margin-bottom: 30px;
    text-align: left;
#squareDiffuserPicts {
    margin-left: 5%;
    width: 800px;
    margin-bottom: 30px;
    clear:

Answer 1

Too much to check through but You are using the following conditionals:
1) Standard CSS.
This is the CSS that will load at any res. If you set a style here it will load in the two conditional's below as well.
2) @media screen and (min-width:990px)
     This is telling the browser to load these styles when the screen is over 990px's wide but you have not excluded anything using max-width so any styles from 1) will be carried over. You could try overwriting them with      !important but its messy and would make more sense to extract the styles from 1)
3) @media screen and (min-width:1100px)
     This is telling the browser to load these styles when the screen is over 1100px but like 2) you are not ignoring anything under this width so it will pick up your base styles as well as your conditional styles from 2)