Hello @soren

Please add these CSS Codes code in the theme.

Css Code to make slider height larger – you can adjust value as your requirement – only change first value not ‘0’

 .slide-text-only .main-slider{
     padding : 160px 0;
   }

Css Code to make logo larger – you can adjust height and width as your requirement

 .site-logo img {
    height: 130px;
    width: 300px;
  } 

Css Code to remove gray transparent box

.slide-text-only .main-slider .regular{
    background: none;
    max-width: fit-content;
  }
  .slide-text-only .main-slider .slick-prev {
    left: 20px;
  }
  .slide-text-only .main-slider .slick-next {
    right: 20px;
  }
  .slide-text-only .main-slider .regular .main-slider-contents{
    max-width: 600px;
  }

To add the above CSS please follow my instruction.
Go to Admin Panel > Appearance > Customize > Additional Css, paste all of the css here then published and refresh. You will see changes

Hope this helps you

Please help us by giving a review if you like our theme and support.
here is the link https://wordpress.org/support/theme/travel-insight/reviews

Thanks in advance for a review

Regards,
Psink

Hello @SOREN

Add these CSS in Addtional Css.

Css For logo

.site-logo img {
    max-height: 180px;
    width: 331px;
}

Css for homepage image

section#main-slider-section {
    padding: 50px 0px;
}

Css for button

.nav-previous, .nav-next {
    display: none;
}

Hope this helps

Regards,
Psink