Please Help me fixing the Slider Length for mobile display

Slider height in mobiles? https://www.themesandco.com/snippet/reduce-height-slider/
Take a look there to understand what you have to do with media queries.

So you resolved those other problems with mobile?

Description: Unable to locate the server named “themesandco.com” — the server does not have a DNS entry. Perhaps there is a misspelling in the server name, or the server no longer exists. Double-check the name and try again.

I Actually Have played with media queries. the snippet which is available in themesandco by the way. But my slider height issue remains the same in terms of mobile display. Need help.

You have this in your child theme style.css:

@media (max-width: 979px){
    .widget-front .round-div {
        border-color: #252423;
    }
}

so looks like you know how to play with them.
You have also this:

#customizr-slider.carousel .item {
height:         345px;
min-height:     345px;
line-height:    345px;
}

This is for all screen widths. What you have to do is to chose proper values of those 3 properties for different viewports:

@media (max-width: 979px){
#customizr-slider.carousel .item {
height:         205px; //change these values !!!
min-height:     205px;
line-height:    205px;
}
}

And so on…
And try to reach that url.

for the slider I have inserted your code for diff view ports. But result is the same.

@media (max-width: 1200px){
#customizr-slider.carousel .item {
height: 200px;
min-height: 200px;
line-height: 200px;
}
}
@media (max-width: 979px){
#customizr-slider.carousel .item {
height: 180px;
min-height: 180px;
line-height: 180px;
}
}
@media (max-width: 767px){
#customizr-slider.carousel .item {
height: 130px;
min-height: 130px;
line-height: 130px;
}
}

@media (max-width: 480px){
#customizr-slider.carousel .item {
height:         90px;
min-height:     90px;
line-height:    90px;
}
}

Of course is the same, you have to put it after this other rule:

#customizr-slider.carousel .item {
height: 345px;
min-height: 345px;
line-height: 345px;
}

You put your media queries before that, ..wrong.
So, put media queries at the bottom of your style.css, would be better.

Yaaaaay! Its sorted.