html - 可扩展站点，菜单背景消失

Question

我是该网站的新手，我在创建可扩展网站时遇到了问题。将屏幕缩小到 650px 以下时会出现问题。出于某种原因，我的菜单背景正在消失。我已经多次检查代码，但找不到我的错误。 请帮忙!

这是我页面的链接:http://mnice.mydevryportfolio.com/portfolio/

这是我目前使用的 Media CSS 代码:

            /************************************************************************************
    smaller than 980
    *************************************************************************************/
    @media screen and (max-width: 980px) {

/* pagewrap */
#pagewrap {
    width: 95%;
}

/* content */
#content {
    width: 60%;
    padding: 3% 4%;
}

/* sidebar */
#sidebar {
    width: 30%;
}
#sidebar .widget {
    padding: 8% 7%;
    margin-bottom: 10px;
}

/* embedded videos */
.video embed,
.video object,
.video iframe {
    width: 100%;
    height: auto;
    min-height: 300px;
}

    }

            /************************************************************************************
    smaller than 650
    *************************************************************************************/
    @media screen and (max-width: 650px) {

/* header */
#header {
    height: auto;
}

/* search form */
#searchform {
    position: absolute;
    top: 5px;
    right: 0;
    z-index: 100;
    height: 40px;
}
#searchform #s {
    width: 70px;
}
#searchform #s:focus {
    width: 150px;
}

/* main nav */
#main-nav {
    position: static;
}

/* site logo */
#site-logo {
    margin: 15px 100px 5px 0;
    position: static;
}

/* site description */
#site-description {
    margin: 0 0 15px;
    position: static;
}

/* content */
#content {
    width: auto;
    float: none;
    margin: 100px 0;
}

/* sidebar */
#sidebar {
    width: 100%;
    margin: 0;
    float: none;
}
#sidebar .widget {
    padding: 3% 4%;
    margin: 0 0 10px;
}

/* embedded videos */
.video embed,
.video object,
.video iframe {
    min-height: 250px;
}

    }

    /************************************************************************
    smaller than 560
    **************************************************************************/
    @media screen and (max-width: 480px) {

/* disable webkit text size adjust (for iPhone) */
html {
    -webkit-text-size-adjust: none;
}

/* main nav */
#main-nav a {
    font-size: 90%;
    padding: 10px 8px;
}

    }

然后是主 CSS 样式页面:

    /************************************************************************
     RESET
     ****************************************************************************/
     html, body, address, blockquote, div, dl, form, h1, h2, h3, h4, h5, h6, ol, p, pre, table, ul,
     dd, dt, li, tbody, td, tfoot, th, thead, tr, button, del, ins, map, object,
     a, abbr, acronym, b, bdo, big, br, cite, code, dfn, em, i, img, kbd, q, samp, small, span,
     strong, sub, sup, tt, var, legend, fieldset {
margin: 0;
padding: 0;
     }

     img, fieldset {
border: 0;
     }

     /* set image max width to 100% */
     img {
max-width: 100%;
height: auto;
width: auto\9; /* ie8 */
     }

     /* set html5 elements to block */
     article, aside, details, figcaption, figure, footer, header, hgroup, menu, nav, section { 
         display: block;
     }

     /************************************************************************************
     GENERAL STYLING
     *************************************************************************************/
     body {
 background: url(images/background.png);
 font: .81em/150% Arial, Helvetica, sans-serif;
 color: #000;
     }
     a {
 color: #026acb;
 text-decoration: none;
 outline: none;
     }
     a:hover {
text-decoration: underline;
     }
     p {
margin: 0 0 1.2em;
padding: 0;
     }

     /* list */
     ul, ol {
margin: 1em 0 1.4em 24px;
padding: 0;
line-height: 140%;
     }
     li {
margin: 0 0 .5em 0;
padding: 0;
     }

     /* headings */
     h1, h2, h3, h4, h5, h6 {
line-height: 1.4em;
margin: 20px 0 .4em;
color: #000;
     }
     h1 {
font-size: 2em;
     }
     h2 {
font-size: 1.6em;
     }
     h3 {
font-size: 1.4em;
     }
     h4 {
font-size: 1.2em;
     }
     h5 {
font-size: 1.1em;
     }
     h6 {
font-size: 1em;
     }

     /* reset webkit search input styles */
     input[type=search] {
-webkit-appearance: none;
outline: none;
     }
     input[type="search"]::-webkit-search-decoration, 
     input[type="search"]::-webkit-search-cancel-button {
display: none;
     }

     /************************************************************************************
     STRUCTURE
     *************************************************************************************/
     #pagewrap {
width: 980px;
margin: 0 auto;
     }

     /************************************************************************************
     HEADER
     *************************************************************************************/
     #header {
position: relative;
height: 180px;
     }

     /* site logo */
     #site-logo {
position: absolute;
top: 0px;
     }
     #site-logo a {
font: bold 30px/100% Arial, Helvetica, sans-serif;
color: #fff;
text-decoration: none;
     }

     /* site description */
     #site-description {
font: italic 100%/130% "Times New Roman", Times, serif;
color: #fff;
position: absolute;
top: 95px;
     }

     /* searchform */
     #searchform {
position: absolute;
right: 10px;
bottom: 6px;
z-index: 100;
width: 160px;
     }
     #searchform #s {
width: 140px;
float: right;
background: #fff;
border: none;
padding: 6px 10px;
/* border radius */
-webkit-border-radius: 5px;
-moz-border-radius: 5px;
border-radius: 5px;
/* box shadow */
-webkit-box-shadow: inset 0 1px 2px rgba(0,0,0,.2);
-moz-box-shadow: inset 0 1px 2px rgba(0,0,0,.2);
box-shadow: inset 0 1px 2px rgba(0,0,0,.2);
/* transition */
-webkit-transition: width .7s;
-moz-transition: width .7s;
transition: width .7s;
     }

              /************************************************************************************
     MAIN NAVIGATION
     *************************************************************************************/
     #main-nav {
width: 100%;
background: #ccc;
margin: 0;
padding: 0;
position: absolute;
left: 0;
bottom: 0;
z-index: 100;
/* gradient */
background: #6a6a6a url(images/nav-bar-bg.png) repeat-x;
background: -webkit-gradient(linear, left top, left bottom, from(#b9b9b9), to(#6a6a6a));
background: -moz-linear-gradient(top,  #b9b9b9,  #6a6a6a);
background: linear-gradient(-90deg, #b9b9b9, #6a6a6a);
/* rounded corner */
-webkit-border-radius: 8px;
-moz-border-radius: 8px;
border-radius: 8px;
/* box shadow */
-webkit-box-shadow: inset 0 1px 0 rgba(255,255,255,.3), 0 1px 1px rgba(0,0,0,.4);
-moz-box-shadow: inset 0 1px 0 rgba(255,255,255,.3), 0 1px 1px rgba(0,0,0,.4);
box-shadow: inset 0 1px 0 rgba(255,255,255,.3), 0 1px 1px rgba(0,0,0,.4);
     }
     #main-nav li {
margin: 0;
padding: 0;
list-style: none;
float: left;
position: relative;
     }
     #main-nav li:first-child {
margin-left: 10px;
     }
     #main-nav a {
line-height: 100%;
font-weight: bold;
color: #fff;
display: block;
padding: 14px 15px;
text-decoration: none;
text-shadow: 0 -1px 0 rgba(0,0,0,.5);
     }
     #main-nav a:hover {
color: #fff;
background: #474747;
/* gradient */
background: -webkit-gradient(linear, left top, left bottom, from(#282828), to(#4f4f4f));
background: -moz-linear-gradient(top,  #282828,  #4f4f4f);
background: linear-gradient(-90deg, #282828, #4f4f4f);
     }

     /************************************************************************************
     CONTENT
     *************************************************************************************/
     #content {
         background-image: url(images/containerbackground_blur.png);
margin: 30px 0 30px;
padding: 20px 35px;
width: 700px;
float: left;
/* rounded corner */
-webkit-border-radius: 8px;
-moz-border-radius: 8px;
border-radius: 8px;
/* box shadow */
-webkit-box-shadow: 0 1px 3px rgba(0,0,0,.4);
-moz-box-shadow: 0 1px 3px rgba(0,0,0,.4);
box-shadow: 0 1px 3px rgba(0,0,0,.4);
     }

     /* post */
     .post {
margin-bottom: 40px;
     }
     .post-title {
margin: 0 0 5px;
padding: 0;
font: bold 26px/120% Arial, Helvetica, sans-serif;
     }
     .post-title a {
text-decoration: none;
color: #000;
     }
     .post-meta {
margin: 0 0 10px;
font-size: 90%;
     }


     .main-image {
margin: 0 0 15px;
text-align: center;
     }

     /************************************************************************************
     SIDEBAR
     *************************************************************************************/
     #sidebar {
width: 200px;
float: right;
margin: 30px 0 30px;
     }
     .widget {
background: #fff;
margin: 0 0 30px;
padding: 10px 20px;
/* rounded corner */
-webkit-border-radius: 8px;
-moz-border-radius: 8px;
border-radius: 8px;
/* box shadow */
-webkit-box-shadow: 0 1px 3px rgba(0,0,0,.4);
-moz-box-shadow: 0 1px 3px rgba(0,0,0,.4);
box-shadow: 0 1px 3px rgba(0,0,0,.4);
     }
     .widgettitle {
margin: 0 0 5px;
padding: 0; 
     }
     .widget ul {
margin: 0;
padding: 0;
     }
     .widget li {
margin: 0;
padding: 6px 0;
list-style: none;
clear: both;
border-top: solid 1px #eee;
     }



     /************************************************************************************
     FOOTER
     *************************************************************************************/
     #footer {
clear: both;
color: #ccc;
font-size: 85%;
     }
     #footer a {
color: #fff;
     }

     /************************************************************************************
     CLEARFIX
     *************************************************************************************/
     .clearfix:after { visibility: hidden; display: block; font-size: 0; content: " "; clear: both; height: 0; }
     .clearfix { display: inline-block; }
     .clearfix { display: block; zoom: 1; }

如有任何帮助，我们将不胜感激!

Answer 1

media.css 第 63 行将 #main-nav 中的 position:static 替换为 bottom:auto;

#main-nav {
    bottom: auto;
}