可变主题切换效果代码

html代码

<div class="c-card">
  <button class="c-theme" id="themePicker"></button>
  <h1 class="c-card__title">Variable Themes</h1>
  <p class="c-card__description">Cycle through 4 themes, from darkest to lightest.</p>
  <div class="c-theme-grid" id="themeGrid"></div><a class="c-button" id="button">Cycle Theme</a>
</div>

js代码

console.clear()

const themes = ['dark', 'sunset', 'sunrise', 'light'];
let count = 0;
const themePicker = document.getElementById('themePicker');
const themeList = document.getElementById('themeGrid');

// Change the CSS variables on the root element, depending on the curent theme
const changeTheme = (theme) => {

    if(count < 3) {
        count += 1;
    } else {
        count = 0
    }

    document.documentElement.style.setProperty('--bg', `var(--${theme}-bg)`);
    document.documentElement.style.setProperty('--border', `var(--${theme}-border)`);
    document.documentElement.style.setProperty('--surface', `var(--${theme}-surface)`);
    document.documentElement.style.setProperty('--text-primary', `var(--${theme}-text-primary)`);
    document.documentElement.style.setProperty('--text-secondary', `var(--${theme}-text-secondary)`);
    document.documentElement.style.setProperty('--primary', `var(--${theme}-primary)`);
    document.documentElement.style.setProperty('--text-inverse', `var(--${theme}-text-inverse)`);

    const themeGrid = themePicker.querySelector('.c-theme__grid')

    if(themeList.querySelector('.c-box--active')) {
        themeList.querySelector('.c-box--active').classList.remove('c-box--active')
    }

    themeList.querySelectorAll('.c-box').forEach(item => {
        if(item.dataset.theme === theme) {
            item.classList.add('c-box--active')
        }
    })

    switch(theme) {
        case theme = 'dark':
            themeGrid.style.top = '0'
            break;
        case theme = 'sunset':
            themeGrid.style.top = '-3.6rem'
            break;
        case theme = 'sunrise':
            themeGrid.style.top = '-7.1rem'
            break;
        case theme = 'light':
            themeGrid.style.top = '-10.7rem'
            break;
    }
}

// Define Icons
const darkIcon = `<svg fill="currentColor" aria-hidden="true" viewBox="0 0 24 24" tabindex="-1" title="Dark"><path d="M10 2c-1.82 0-3.53.5-5 1.35C7.99 5.08 10 8.3 10 12s-2.01 6.92-5 8.65C6.47 21.5 8.18 22 10 22c5.52 0 10-4.48 10-10S15.52 2 10 2z"></path></svg>`

const sunsetIcon = `<svg fill="currentColor" aria-hidden="true" viewBox="0 0 24 24" tabindex="-1" title="Sunset"><path d="M20 8.69V4h-4.69L12 .69 8.69 4H4v4.69L.69 12 4 15.31V20h4.69L12 23.31 15.31 20H20v-4.69L23.31 12 20 8.69zM12 18c-.89 0-1.74-.2-2.5-.55C11.56 16.5 13 14.42 13 12s-1.44-4.5-3.5-5.45C10.26 6.2 11.11 6 12 6c3.31 0 6 2.69 6 6s-2.69 6-6 6z"></path></svg>`

const sunriseIcon = `<svg fill="currentColor" aria-hidden="true" viewBox="0 0 24 24" tabindex="-1" title="Sunrise"><path d="M20 15.31 23.31 12 20 8.69V4h-4.69L12 .69 8.69 4H4v4.69L.69 12 4 15.31V20h4.69L12 23.31 15.31 20H20v-4.69zM12 18V6c3.31 0 6 2.69 6 6s-2.69 6-6 6z"></path></svg>`

const lightIcon = `<svg fill="currentColor" aria-hidden="true" viewBox="0 0 24 24" tabindex="-1" title="Light"><path d="M20 8.69V4h-4.69L12 .69 8.69 4H4v4.69L.69 12 4 15.31V20h4.69L12 23.31 15.31 20H20v-4.69L23.31 12 20 8.69zM12 18c-3.31 0-6-2.69-6-6s2.69-6 6-6 6 2.69 6 6-2.69 6-6 6zm0-10c-2.21 0-4 1.79-4 4s1.79 4 4 4 4-1.79 4-4-1.79-4-4-4z"></path></svg>`

// Content and click function for the theme picker
themePicker.innerHTML = `
    <div class="c-theme__grid">
        ${darkIcon}
        ${sunsetIcon}
        ${sunriseIcon}
        ${lightIcon}
    </div>
`

themePicker.onclick = () => {
    changeTheme(themes[count])
}

document.getElementById('button').onclick = () => {
    changeTheme(themes[count])
}

const capitalized = (word) => {
    return word.charAt(0).toUpperCase() + word.slice(1)
}

themes.forEach((theme, i) => {
    let box = document.createElement('button');
    box.dataset.theme = theme
    box.onclick = () => {
        changeTheme(themes[i])
    }
    box.classList = 'c-box';
    box.style.setProperty('--bg', `var(--${theme}-bg)`);
    box.style.setProperty('--border', `var(--${theme}-border)`);
    box.style.setProperty('--surface', `var(--${theme}-surface)`);
    box.style.setProperty('--text-primary', `var(--${theme}-text-primary)`);
    box.style.setProperty('--text-secondary', `var(--${theme}-text-secondary)`);
    box.style.setProperty('--primary', `var(--${theme}-primary)`);
    box.style.setProperty('--text-inverse', `var(--${theme}-text-inverse)`);

    const iconRender = (theme) => {
        switch(theme) {
            case theme = 'dark':
                return darkIcon
                break;
            case theme = 'sunset':
                return sunsetIcon
                break;
            case theme = 'sunrise':
                return sunriseIcon
                break;
            case theme = 'light':
                return lightIcon
                break;
        }
    }

    box.innerHTML = `
        <div class="c-box__title">
            <span class="c-box__icon">
                ${iconRender(theme)}
            </span>
            <label>${capitalized(theme)}</label>
        </div>
        <div class="c-box__swatches">
            <span class="c-swatch" style="background: var(--bg)" title="bg"></span>
            <span class="c-swatch" style="background: var(--border)" title="border"></span>
            <span class="c-swatch" style="background: var(--surface)" title="surface"></span>
            <span class="c-swatch" style="background: var(--text-primary)" title="text-primary"></span>
            <span class="c-swatch" style="background: var(--text-secondary)" title="text-secondary"></span>
            <span class="c-swatch" style="background: var(--primary)" title="primary"></span>
            <span class="c-swatch" style="background: var(--text-inverse)" title="text-inverse"></span>
        </div>
    `
    themeList.appendChild(box)
})

changeTheme(themes[0])

css代码

@import url("https://fonts.googleapis.com/css2?family=Figtree:wght@400;700&display=swap");
@charset "UTF-8";
:root {
  --dark-bg: #101214;
  --dark-border: #22272B;
  --dark-surface: #161A1D;
  --dark-text-primary: #DEE4EA;
  --dark-text-secondary: #738496;
  --dark-primary: #1D7AFC;
  --dark-text-inverse: #FFFFFF;
  --sunset-bg: #151c19;
  --sunset-border: #424f4a;
  --sunset-surface: #2f3834;
  --sunset-text-primary: #ecd2c5;
  --sunset-text-secondary: #C0AB92;
  --sunset-primary: #C0AB92;
  --sunset-text-inverse: #151c19;
  --sunrise-bg: #ecd2c5;
  --sunrise-border: #d7c9c6;
  --sunrise-surface: #f3e8e5;
  --sunrise-text-primary: #4f2733;
  --sunrise-text-secondary: #685844;
  --sunrise-primary: #a04d66;
  --sunrise-text-inverse: #f3e8e5;
  --light-bg: #F7F8F9;
  --light-border: #F1F2F4;
  --light-surface: #FFFFFF;
  --light-text-primary: #091E42;
  --light-text-secondary: #626F86;
  --light-primary: #1D7AFC;
  --light-text-inverse: #FFFFFF;
  --bg: var(--dark-bg);
  --border: var(--dark-border);
  --surface: var(--dark-surface);
  --text-primary: var(--dark-text-primary);
  --text-secondary: var(--dark-text-secondary);
  --primary: var(--dark-primary);
  --text-inverse: var(--dark-text-inverse);
}

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

html {
  box-sizing: inherit;
  font-size: 62.5%;
}

html, body {
  margin: 0;
  padding: 0;
  width: 100%;
  height: 100%;
}

body {
  font-size: 1.6rem;
  font-family: "Figtree", system-ui, sans-serif;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 1.2rem;
  background: var(--bg);
  color: var(--text-secondary);
}

.c-card {
  width: 100%;
  max-width: 650px;
  border: 1px solid var(--border);
  border-radius: 1.6rem;
  padding: 3.2rem;
  background: var(--surface);
  position: relative;
  box-shadow: 0.3px 0.5px 0.7px rgba(0, 0, 0, 0.08), 0.8px 1.6px 2px -0.8px rgba(0, 0, 0, 0.08), 2.1px 4.1px 5.2px -1.7px rgba(0, 0, 0, 0.08), 5px 10px 12.6px -2.5px rgba(0, 0, 0, 0.08);
}
.c-card__title {
  margin: 0 0 0.8rem;
  padding: 0;
  line-height: 1.2;
  font-size: 4rem;
  color: var(--text-primary);
}
.c-card__description {
  margin: 0;
  padding: 0;
  line-height: 150%;
  font-size: 2rem;
  color: var(--text-secondary);
}

.c-button {
  display: inline-flex;
  padding: 1.2rem 2rem;
  background: var(--primary);
  border-radius: 0.8rem;
  line-height: 1;
  cursor: pointer;
  color: var(--text-inverse);
  font-weight: 700;
  user-select: none;
  position: relative;
  transition: all 120ms ease-out;
}
.c-button:hover, .c-button:focus {
  outline: none;
  transform: scale(1.03);
}

.c-theme {
  position: absolute;
  top: 2.4rem;
  right: 2.4rem;
  width: 4rem;
  height: 4rem;
  cursor: pointer;
  display: inline-block;
  overflow: hidden;
  padding: 0;
  margin: 0;
  background: transparent;
  color: var(--text-primary);
  border: 1px solid transparent;
  border-radius: 0.8rem;
  padding: 0.4rem;
  transition: all 120ms ease-out;
}
.c-theme:hover, .c-theme:focus {
  border-color: var(--border);
}
.c-theme:after, .c-theme:before {
  content: "";
  position: absolute;
  z-index: 10;
}
.c-theme:after {
  top: 0;
  left: 0;
  right: 0;
  height: 0.8rem;
  background: linear-gradient(to bottom, var(--surface), transparent);
}
.c-theme:before {
  bottom: 0;
  left: 0;
  right: 0;
  height: 0.8rem;
  background: linear-gradient(to top, var(--surface), transparent);
}
.c-theme:focus {
  outline: none;
}
.c-theme__grid {
  position: relative;
  width: 3.2rem;
  transition: all 240ms ease-out;
}
.c-theme svg {
  width: 3.2rem;
  height: 3.2rem;
}
.c-theme svg:focus {
  outline: none;
}

.c-box {
  display: flex;
  width: 100%;
  flex-direction: column;
  background: var(--bg);
  color: var(--text-secondary);
  position: relative;
  padding: 1.6rem;
  border-radius: 1.2rem;
  border: 1px solid var(--border);
  user-select: none;
  cursor: pointer;
  transition: all 120ms ease-out;
}
.c-box:hover, .c-box:focus {
  transform: scale(1.03);
}
.c-box__title {
  display: flex;
  align-items: center;
  width: 100%;
}
.c-box__icon {
  width: 1.6rem;
  height: 1.6rem;
  margin-right: 0.4rem;
}
.c-box__swatches {
  display: flex;
  flex-wrap: wrap;
  margin-top: 0.8rem;
}
.c-box--active {
  outline: 4px solid var(--primary);
}
.c-box--active:after {
  content: "√";
  position: absolute;
  top: -1.2rem;
  right: -1.2rem;
  height: 2.4rem;
  width: 2.4rem;
  background: var(--primary);
  border-radius: 999px;
  color: var(--text-inverse);
  display: inline-flex;
  align-items: center;
  justify-content: center;
}

.c-swatch {
  width: 2rem;
  height: 2rem;
  display: inline-block;
  border-radius: 999px;
  border: 1px solid var(--border);
  margin-right: -0.8rem;
  box-shadow: 0px 1px 1px rgba(0, 0, 0, 0.12), 0px 0px 0px 1px rgba(0, 0, 0, 0.08);
}

.c-theme-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  grid-gap: 1.6rem;
  margin: 3.2rem 0;
}
@media (max-width: 700px) {
  .c-theme-grid {
    grid-template-columns: repeat(2, 1fr);
  }
}