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maintain the height of the content floating right same as the sibling div floating left, responsive

I have the below structure:
<div class="wrapper1">
<div class="left">some img here with 100% width and some text which dispaly on hovering over the image</div>
<div class="right">some content here</div>
</div>
<div class="items">
<ul><li></li></ul>
</div>
The above layout is used for a responsive site. so on resizing the window or on page load on different devices the content in the right div should always remain of the same height as that of the left div.
Also, I have to append a link "more >>" responsively where the last character of the content in the right div ends.
I have used overflow hidden property for the right div and I am trying to give some height to the right div based on the window width using media queries. Have tried different things but since the text amount changes responsively it is becoming difficult to append more link to the last character.
Also, i tried using jquery/jscript to detect the height of the left div on page load so as to set the height of the right div same as that using .outerheight() property but on initial load of the page I am not able to get the height in pixels since the width of the image inside the left div is set to 100%.
Also, there are 2 main issues here,
1)I set the height of the left div same as that of the right div responsively. Here the extra content to be displayes in the right div should always be hidden.
2) append more link just where last last charcter of the last visible line of the content on the left div is responsively.
Could anyone please suggest some solution.

With flexbox the columns share the same height automatically, without any javascript.
.wrapper {
display: flex;
}
.left {
background: yellow;
flex: 1;
}
.right {
background: red;
flex: 1;
}
<div class="wrapper">
<div class="left">some img here with 100% width and some text which dispaly on hovering over the image</div>
<div class="right">some content here</div>
</div>

I believe all your problem will be solved if and only if you use bootstrap css rules the grid system and furthermore make a class with specific height and assign it to the div . And more advice get familiar with media query in css3
Create a div with relative position for appending links and make it in the bottom of the container div

Am I stuck with forcing fixed image size for image tags?

I have a website that contains a side bar and sometimes an image of a very large size (about 800 pixels wide) but I scripted the code so that if a screen resolution is too small, the image shrinks and scales into the small space perfectly according to multiple browsers I tested the site on. I tested the site with the demo version of sortsite by powermapper at:
http://try.powermapper.com/Demo/
It then goes on to complain that "Omitting IMG WIDTH or HEIGHT attributes means page text jumps about as images load. Usability.gov 14:3"
I understand that and I try to include those attributes, the image does not scale correctly.
This is the CSS I use on the image itself to scale it if I had a monitor with a max screen width of 800 pixels:
#media screen and (max-width: 600px){#X IMG{width: 100%}}
I specify 600px because I reserved 200 pixels for the sidebar.
I don't think javascript will be an answer because during the page load, the image placeholder will jump to the new size, and if I placed the code near the beginning, it will delay the the rest of the page from loading somewhat.
I was also thinking using div tags and setting the background to the image, but the problem there is that users won't be able to save it and the rest of the images on my site are part of a CSS sprite sheet.
I also am looking for a solution that will work with as many web browsers as possible even if javascript is disabled.
Any ideas for an answer?

This rule, while correct, went out the window when responsive design came into being:
Omitting IMG WIDTH or HEIGHT attributes means page text jumps about
as images load. Usability.gov 14:3
If you're always going to be using a given aspect ratio, then you can set up your code as below. If you set your width and height attributes on your img tag and you set max-width: 100% (or similar) in your CSS, as people often do when developing responsive sites, then your text will still jump around when the image loads, because it's initial height will be what you specify in your markup, and then when the image loads, the browser will maintain the aspect ratio required for max-width: 100% to work and end up shrinking the height - so that doesn't really help you adhere to your usability rule either.
.img {
background-size: cover;
background: center no-repeat;
}
.ar {
height:0;
padding: 0 0 56.25% /* 16:9 aspect ratio */
}
<div class="img" style="background-image: url(https://placekitten.com/g/500/500);">
<div class="ar"></div>
</div>

Try setting the width and height and then just adjusting width and height with your media queries (rather than max-width and percent width). You shouldn't encounter any scaling problems then.

#media screen and (max-width: 600px){#X IMG{width: 100%}}
This means that IMG will have full width of it's first parent. That parent might not be X element. Are you sure you want that?
Example:
<div id='X'>
<div><div><div><div>
<img src=''>
</div></div></div></div>
</div>
If you are trying to fix x:y img ratio that put height:auto; after width:100%;
Calculate width or height and always use auto for other property to preserve image scaling.

Set the scrollable height of an entire page regardless of content?

Is there a way using css and html to control the maximum scrollable height of a page, regardless of the content which is present on the page?
For a concrete, hypothetical example: say the <body> is incredibly simple - a <div> which is 5000px tall. How would you set the scrollable height to be only 2000px?
Thus it would appear that the 2000th pixel is the last pixel on the page. The browser's scroll bar would appear to be at the bottom, not just "stuck" halfway down the page. Am I missing something simple to achieve this behavior? I would prefer pure css/html because it seems like it should be doable, but I would accept js.

You can do something like this
HTML
<div class="outer">
<div class="inner">
<!--your content here-->
</div>
</div>
CSS
.outer {
height:2000px;
overflow:auto;
}
.inner {
height:5000px;
overflow:hidden;
}

You should set the body height to a specific number and set overflow to hidden.
body{
height:2000px;
overflow:hidden;
}
Made an example here

Use max-height or height css properties and overflow:hidden on your container element. It will hide everything that is greater than the height you specify, therefore limiting the scrollbar height.
I should also mention that you can use overflow-y:hidden will achieve the same thing, but will only affect top and bottom edges of an element. See more details here.

make the whole page scroll beneath a certain height at the top without any scroll bar

html:
<div class="div_fixed"></div>
<div class="other_content">
content goes here
</div>
css:
.div_fixed{
position:fixed;
height:40px;
}
.other_content{
height:200px;
}
The div_fixed will remain fixed at the top position of the page.
But as the page scrolls up, the content of the div other_content will vanish just at the lower edge of the div div_fixed .
In the case of scrolling down the invisible content of other_content will begin to be visible from the lower edge of the div_fixed
How to achieve that ?
EDIT: no scroll bar should appear for any div

Use overflow: hidden to get rid of scrollbars

Is this what you're looking for? http://jsfiddle.net/BCRPa/

I've taken your HTML/CSS and added a bit on a jsFiddle - I think in order to achieve the effect you're looking for, you just need to make your content actually tall enough to be scrollable. At 200px high and one line of text, nothing is going to scroll.
So I made your other_content div taller, and then added a top: 0 to your .div_fixed selector, to keep it stuck to the top of the screen, and a margin-top: 40px to the .other_content div in order to have it start below the floating div.
If you want it to be a navbar-type thing, you can of course add a width: 100% to the .div_fixed.
All of this should transfer into a container div (with position: relative) fairly easily as well if you want, although you may have to re-position the fixed div.

jquery mobile, images have a small black border around them

I'm using jquery mobile, and I have a image that I would like to fit the screen from right to left, with no gaps. However, if I just put the image without doing anything to it like <img src="image.png />", it turns out with a small black border around it. This stays despite me setting width=100% in the css. How can I remove this border?
Adding some code:
<div data-role="content" style="background-color: #000000">
<div id="slogandiv">
<img src="slogan.jpg" id="slogan" width="100%" height="45%"/>
</div>

I just did this. It is because that the data-role = "content" has a automated padding of 15px.
I went into the .css file and removed this. search for ui-content. remember in the ui-content, listview, that it has -15 so change this to 0 aswell.

A CSS directive of width: 100% for your image simply means that the browser should display the image at its actual size (if it can), it won't stretch it to some other size. This may explain why you have a slight border around it, as the image doesn't quite scale to the full width of the viewport. You could try tinkering with the img tag's margin and padding settings, but I suspect the approach that will work best for you is to display the image a different way.
Have you tried manipulating the CSS of the containing element? Say you have a paragraph class called .container. You could do something like this:
.container {
background: url('image.png') no-repeat;
background-size: contain;
width: 480px;
height: 240px
}
… this will use your image as before, but this time the background-size attribute of contain will force it to fill the dimensions of the parent element (the height and width of which we have defined above).
background-size is new in CSS3 and therefore not uniformly-supported, but it's in WebKit and several other browsers. Read more: A List Apart: Supersize that Background, Please!