make image slider full-width responsive

I'm trying to do a image slider full-width responsive with html and css only. But i got stuck at the moment to put slider full-width responsive. Help me pls.

HTML

        <ul class="slides">
            <input type="radio" name="radio-btn" id="img-1" checked />
            <li class="slide-container">
                <div class="slide">
                    <img id src="assets/images/Slide/bilhete.png" />
                </div>
                <div class="nav">
                    <label for="img-6" class="prev">&#x2039;</label>
                    <label for="img-2" class="next">&#x203a;</label>
                </div>
            </li>

            <input type="radio" name="radio-btn" id="img-2" />
            <li class="slide-container">
                <div class="slide">
                  <img src="assets/images/Slide/aplausos.png" />
                </div>
                <div class="nav">
                    <label for="img-1" class="prev">&#x2039;</label>
                    <label for="img-3" class="next">&#x203a;</label>
                </div>
            </li>

            <input type="radio" name="radio-btn" id="img-3" />
            <li class="slide-container">
                <div class="slide">
                  <img src="assets/images/Slide/Pa%C3%A7os.png" />
                </div>
                <div class="nav">
                    <label for="img-2" class="prev">&#x2039;</label>
                    <label for="img-4" class="next">&#x203a;</label>
                </div>
            </li>

            <input type="radio" name="radio-btn" id="img-4" />
            <li class="slide-container">
                <div class="slide">
                  <img src="assets/images/Slide/natal.png" />
                </div>
                <div class="nav">
                    <label for="img-3" class="prev">&#x2039;</label>
                    <label for="img-5" class="next">&#x203a;</label>
                </div>
            </li>

            <input type="radio" name="radio-btn" id="img-5" />
            <li class="slide-container">
                <div class="slide">
                  <img src="http://farm9.staticflickr.com/8055/8098750623_66292a35c0_z.jpg" />
                </div>
                <div class="nav">
                    <label for="img-4" class="prev">&#x2039;</label>
                    <label for="img-6" class="next">&#x203a;</label>
                </div>
            </li>

            <input type="radio" name="radio-btn" id="img-6" />
            <li class="slide-container">
                <div class="slide">
                  <img src="http://farm9.staticflickr.com/8195/8098750703_797e102da2_z.jpg" />
                </div>
                <div class="nav">
                    <label for="img-5" class="prev">&#x2039;</label>
                    <label for="img-1" class="next">&#x203a;</label>
                </div>
            </li>
        </ul>

CSS

.slides {

padding: 0;
width: 868px;
height: 637px;
display: block;
margin: auto;
position: relative;

}

.slides * {

user-select: none;
-ms-user-select: none;
-moz-user-select: none;
-khtml-user-select: none;
-webkit-user-select: none;

}

.slides input {

display: none; 

}

.slide-container {

display: block;

}

.slide {

top: 0;
opacity: 0;
width: 868px;
height: 637px;
cursor: pointer;
display: block;
position: absolute;

transition: all .7s ease-in-out;

}

.slides img {

width: 100%;
height: 100%;

}

.nav label {

height: 100%;
display: none;
position: absolute;


z-index: 9;
cursor: pointer;

transition: opacity .2s;

color: #FFF;
font-size: 50pt;
text-align: center;
padding: 16px;
line-height: 637px;

}

.slide:hover + .nav label {

opacity: 0.5; 

}

.nav .next {

right: 0; 

}

input:checked + .slide-container .slide {

opacity: 1;

transform: scale(1);

transition: opacity 1s ease-in-out;

}

input:checked + .slide-container .nav label {

display: block;

}

Any help is going to be appreciated.... I have to use css and html only.