CSS KP 02 — Utility Classes 01 -flex, grisr, color, typography

Utility Classes

• Single purpose classes, focused on ONE aspect of styling.
• Modular friendly so write a lot less code in the long run.
• Write CSS class first then utilize that CSS classname in HTML.
• Benefits: 1. Rapid development. 2. easier maintenance.

/* ------------------- */
/* Utility classes     */
/* ------------------- */

/* general */
.flex {
    display: flex;
    gap: var(--gap, 1rem);
}
.grid {
    display: grid;
    gap: var(--gap, 1rem);
}
.container {
    padding-inline: 2em;
    margin-inline: auto;
    max-width: 60rem;
}

Screen reader only for the accessibility. It doesn’t show, but it reads

/* ------------------- */
/* Utility classes     */
/* ------------------- */

/* screen reader only */
.sr-only {
  position: absolute; 
  width: 1px;
  height: 1px;
  padding: 0;
  margin: -1px; 
  overflow: hidden;
  clip: rect(0, 0, 0, 0);
  white-space: nowrap; /* added line */
  border: 0;
}

html

<div class = "flex container"> 
            <div class="box sr-only">a</div>
            <div class="box">b</div>
            <div class="box">c</div>
            <div class="box">d</div>
         </div>

Utility classes color

css

:root {
    /* colors */
    --clr-dark: 230 35% 7%;
    --clr-light: 231 77% 90%;
    --clr-white: 0 0% 100%;
}

/* colors */
.bg-dark { background-color: hsl( var(--clr-dark) );}
.bg-accent { background-color: hsl( var(--clr-light) );}
.bg-white { background-color: hsl( var(--clr-white) );}

.text-dark { color: hsl( var(--clr-dark) );}
.text-accent { color: hsl( var(--clr-light) );}
.text-white { color: hsl( var(--clr-white) );}

html

<div class="container">
            <h1>Design system</h1>
            
            
            <div class="bg-accent text-dark" style="padding: 1rem">
                light blue bg, with dark text
            </div>
            
            <div class="bg-white text-dark" style="padding: 1rem">
                white bg, with dark text
            </div>
            
            <div class="component-ex text-white" style="padding: 1rem">
                light blue bg with a 20% alpha and white text
            </div>
            
        </div>

css

//CSS write the custom css for that element
.component-ex {
    background-color: hsl( var(--clr-light) / .2);
}

Utility Class Typography

:root {
    /* font-sizes */
    /* 150px */
    --fs-900: 9.375rem;
    
    /* 100px */
    --fs-800: 6.25rem;
    
    /* 56px */
    --fs-700: 3.5rem;
    
    /* 32px */
    --fs-600: 2rem;
    
    /* 28px */
    --fs-500: 1.75rem;
    
    /* 18px */
    --fs-400: 1.125rem;
    
    /* 16px */
    --fs-300: 1rem;
    
    /* 14px */
    --fs-200: 0.875rem;
   
    /* font-families */
    --ff-serif: "Bellefair", serif;
    --ff-sans-cond: "Barlow Condensed", sans-serif;
    --ff-sans-normal: "Barlow", sans-serif;
}

/* typography */

.ff-serif { font-family: var(--ff-serif); } 
.ff-sans-cond { font-family: var(--ff-sans-cond); } 
.ff-sans-normal { font-family: var(--ff-sans-normal); } 

.letter-spacing-1 { letter-spacing: 4.75px; } 
.letter-spacing-2 { letter-spacing: 2.7px; } 
.letter-spacing-3 { letter-spacing: 2.35px; } 

.uppercase { text-transform: uppercase; }

.fs-900 { font-size: var(--fs-900); }
.fs-800 { font-size: var(--fs-800); }
.fs-700 { font-size: var(--fs-700); }
.fs-600 { font-size: var(--fs-600); }
.fs-500 { font-size: var(--fs-500); }
.fs-400 { font-size: var(--fs-400); }
.fs-300 { font-size: var(--fs-300); }
.fs-200 { font-size: var(--fs-200); }

.fs-900,
.fs-800,
.fs-700,
.fs-600 {
    line-height: 1.1;
}

custom utility class for numbered title

//CSS

.numbered-title {
    font-family: var(--ff-sans-cond);
    font-size: var(--fs-500);
    text-transform: uppercase;
    letter-spacing: 4.72px; 
}

.numbered-title span {
    margin-right: .5em;
    font-weight: 700;
    color: hsl( var(--clr-white) / .25);
}

html

<h2 class="numbered-title"><span>01</span> colors</h2>
<h2 class="numbered-title"><span>02 </span>Typography</h2>

in one place:

css

/* ------------------- */
/* ---utility class--- */
/* ------------------- */
/* ------------------- */
/* ------------------- */
/* Custom properties   */
/* ------------------- */

:root {
    /* colors */
    --clr-dark: 230 35% 7%;
    --clr-light: 231 77% 90%;
    --clr-white: 0 0% 100%;
    
    /* font-sizes */
    /* 150px */
    --fs-900: 9.375rem;
    
    /* 100px */
    --fs-800: 6.25rem;
    
    /* 56px */
    --fs-700: 3.5rem;
    
    /* 32px */
    --fs-600: 2rem;
    
    /* 28px */
    --fs-500: 1.75rem;
    
    /* 18px */
    --fs-400: 1.125rem;
    
    /* 16px */
    --fs-300: 1rem;
    
    /* 14px */
    --fs-200: 0.875rem;
    
    /* font-families */
    --ff-serif: "Bellefair", serif;
    --ff-sans-cond: "Barlow Condensed", sans-serif;
    --ff-sans-normal: "Barlow", sans-serif;
}


/* ------------------- */
/* Reset               */
/* ------------------- */

/* https://piccalil.li/blog/a-modern-css-reset/ */

/* Box sizing */
*,
*::before,
*::after {
    box-sizing: border-box;
}

/* Reset margins */
body,
h1,
h2,
h3,
h4,
h5,
p,
figure,
picture {
    margin: 0; 
}

h1,
h2,
h3,
h4,
h5,
h6,
p {
    font-weight: 400;
}

/* set up the body */
body {
    font-family: var(--ff-sans-normal);
    font-size: var(--fs-400);
    color: hsl( var(--clr-white) );
    background-color: hsl( var(--clr-dark) );
    line-height: 1.5;
    min-height: 100vh;
}

/* make images easier to work with */
img,
picutre {
    max-width: 100%;
    display: block;
}

/* make form elements easier to work with */
input,
button,
textarea,
select {
    font: inherit;
}

/* remove animations for people who've turned them off */
@media (prefers-reduced-motion: reduce) {  
  *,
  *::before,
  *::after {
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
    scroll-behavior: auto !important;
  }
}




/* ------------------- */
/* Utility classes     */
/* ------------------- */

/* general */

.flex {
    display: flex;
    gap: var(--gap, 1rem);
}

.grid {
    display: grid;
    gap: var(--gap, 1rem);
}

.flow > * + * { 
    margin-top: 1rem;
    outline: 1px solid red;
}

.container {
    padding-inline: 2em;
    margin-inline: auto;
    max-width: 80rem;
}

.sr-only {
  position: absolute; 
  width: 1px;
  height: 1px;
  padding: 0;
  margin: -1px; 
  overflow: hidden;
  clip: rect(0, 0, 0, 0);
  white-space: nowrap; /* added line */
  border: 0;
}


/* colors */

.bg-dark { background-color: hsl( var(--clr-dark) );}
.bg-accent { background-color: hsl( var(--clr-light) );}
.bg-white { background-color: hsl( var(--clr-white) );}

.text-dark { color: hsl( var(--clr-dark) );}
.text-accent { color: hsl( var(--clr-light) );}
.text-white { color: hsl( var(--clr-white) );}


/* typography */

.ff-serif { font-family: var(--ff-serif); } 
.ff-sans-cond { font-family: var(--ff-sans-cond); } 
.ff-sans-normal { font-family: var(--ff-sans-normal); } 

.letter-spacing-1 { letter-spacing: 4.75px; } 
.letter-spacing-2 { letter-spacing: 2.7px; } 
.letter-spacing-3 { letter-spacing: 2.35px; } 

.uppercase { text-transform: uppercase; }

.fs-900 { font-size: var(--fs-900); }
.fs-800 { font-size: var(--fs-800); }
.fs-700 { font-size: var(--fs-700); }
.fs-600 { font-size: var(--fs-600); }
.fs-500 { font-size: var(--fs-500); }
.fs-400 { font-size: var(--fs-400); }
.fs-300 { font-size: var(--fs-300); }
.fs-200 { font-size: var(--fs-200); }

.fs-900,
.fs-800,
.fs-700,
.fs-600 {
    line-height: 1.1;
}

Reference: Kevin Powell!! https://v2.scrimba.com/build-a-space-travel-website-c014/~0c