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HTML

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CSS

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CSS Base

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JavaScript

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HTML 

              
                <div class="banner">This demo uses the <code>:has()</code> selector, which your browser doesn’t support. As of 2023-01-27, try again in the latest version of any browser but Firefox.</div>

<h1>CTA ‘L’ sign CSS</h1>
<div class="sign">
    <div class="lines">
        <div class="line" data-line="red"></div>
        <div class="line" data-line="blue"></div>
        <div class="line" data-line="brown"></div>
        <div class="line" data-line="green"></div>
        <div class="line" data-line="orange"></div>
        <div class="line" data-line="purple"></div>
        <div class="line" data-line="pink"></div>
        <div class="line" data-line="yellow"></div>
    </div>
    <div class="sign-content" contenteditable>Edit This Text</div>
</div>
<form>
    <label><input type="checkbox" name="red" checked> Red line</label>
    <label><input type="checkbox" name="blue"> Blue line</label>
    <label><input type="checkbox" name="brown" checked> Brown line</label>
    <label><input type="checkbox" name="green"> Green line</label>
    <label><input type="checkbox" name="orange"> Orange line</label>
    <label><input type="checkbox" name="purple" checked> Purple line</label>
    <label><input type="checkbox" name="pink"> Pink line</label>
    <label><input type="checkbox" name="yellow"> Yellow line</label>
</form>
!

CSS 

              
                @import url("https://assets.noahliebman.net/nimbus-sans/nimbussansl_bold_macroman/stylesheet.css");

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

body {
    display: flex;
    flex-direction: column;
    align-items: center;
    font-family: "Helvetica", "nimbus_sans_lbold", "Arial", sans-serif;
    gap: 1.6rem;
    font-size: 1.2rem;
    background-color: darkcyan;
}

:root {
    /* https://www.transitchicago.com/developers/branding/ */
    --color-red-line: rgb(227 55 25);
    --color-blue-line: rgb(0 157 220);
    --color-brown-line: rgb(118 66 0);
    --color-green-line: rgb(0 169 79);
    --color-orange-line: rgb(244 120 54);
    --color-purple-line: rgb(73 47 146);
    --color-pink-line: rgb(243 139 185);
    --color-yellow-line: rgb(255 232 0);
    --color-sign-gray: rgb(86 90 92);
}

.sign {
    font-size: clamp(1.30rem, calc(-0.05rem + 6.73vw), 5.00rem);
    height: 1.8em;
    aspect-ratio: 8;
    display: grid;
    grid-template-columns: 1fr 4fr 1fr;
    color: white;
    background-color: white;
    font-weight: 600;
    letter-spacing: -.03em;
    box-shadow: 2px 3px 8px 0 #0009;
}

.sign-content {
    grid-area: 1 / 2 / -1 / -2;
    display: grid;
    background-color: var(--color-sign-gray);
    place-items: center;
}

.sign-content:focus {
    outline: none;
}

.lines {
    grid-area: 1 / 1 / -1 / -1;
    display: grid;
    gap: .07em;
}

.line {
    display: none;
}

.line[data-line=red] {
    background-color: var(--color-red-line);
}
.line[data-line=blue] {
    background-color: var(--color-blue-line);
}
.line[data-line=brown] {
    background-color: var(--color-brown-line);
}
.line[data-line=green] {
    background-color: var(--color-green-line);
}
.line[data-line=orange] {
    background-color: var(--color-orange-line);
}
.line[data-line=purple] {
    background-color: var(--color-purple-line);
}
.line[data-line=pink] {
    background-color: var(--color-pink-line);
}
.line[data-line=yellow] {
    background-color: var(--color-yellow-line);
}

.sign:has(~ form input[name=red]:checked) .line[data-line=red],
.sign:has(~ form input[name=blue]:checked) .line[data-line=blue],
.sign:has(~ form input[name=brown]:checked) .line[data-line=brown],
.sign:has(~ form input[name=green]:checked) .line[data-line=green],
.sign:has(~ form input[name=orange]:checked) .line[data-line=orange],
.sign:has(~ form input[name=purple]:checked) .line[data-line=purple],
.sign:has(~ form input[name=pink]:checked) .line[data-line=pink],
.sign:has(~ form input[name=yellow]:checked) .line[data-line=yellow] {
    display: revert;
}

form {
    display: flex;
    flex-wrap: wrap;
    gap: .4rem;
    justify-content: center;

}

label {
    color: white;
    font-weight: bold;
    padding-block: .6rem;
    padding-inline: .8rem;
    border-radius: 8px;
}

label:has(input[name=red]) {
    background-color: var(--color-red-line);
}
label:has(input[name=blue]) {
    color: black;
    background-color: var(--color-blue-line);
}
label:has(input[name=brown]) {
    background-color: var(--color-brown-line);
}
label:has(input[name=green]) {
    background-color: var(--color-green-line);
}
label:has(input[name=orange]) {
    background-color: var(--color-orange-line);
}
label:has(input[name=purple]) {
    background-color: var(--color-purple-line);
}
label:has(input[name=pink]) {
    color: black;
    background-color: var(--color-pink-line);
}
label:has(input[name=yellow]) {
    color: black;
    background-color: var(--color-yellow-line);
}

h1 {
    text-align: center;
    font-size: clamp(2.80rem, calc(2.00rem + 4.00vw), 4.00rem);
    margin: 0;
    color: transparent;
    background-image: linear-gradient(
        to right,
        var(--color-red-line) 12.5%,
        var(--color-blue-line) 12.5%,
        var(--color-blue-line) 25%,
        var(--color-brown-line) 25%,
        var(--color-brown-line) 37.5%,
        var(--color-green-line) 37.5%,
        var(--color-green-line) 50%,
        var(--color-orange-line) 50%,
        var(--color-orange-line) 62.5%,
        var(--color-purple-line) 62.5%,
        var(--color-purple-line) 75%,
        var(--color-pink-line) 75%,
        var(--color-pink-line) 87.5%,
        var(--color-yellow-line) 87.5%
    );
    background-clip: text;
    -webkit-background-clip: text;
    -webkit-text-stroke: 1px #0009;
}

.banner {
    font-size: 2rem;
    font-weight: bold;
    border: 2px solid black;
    border-radius: 16px;
    background-image: repeating-linear-gradient(
        -45deg,
        var(--color-red-line),
        var(--color-red-line) 16px,
        var(--color-orange-line) 16px,
        var(--color-orange-line) 32px
    );
    max-width: 50ch;
    padding: 16px;
}

@supports selector(:has(a)) {
    .banner {
        display: none;
    }
}
!

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