The button, styled using CSS Flexbox, includes primary, secondary, and tertiary styles, all structured within nested CSS for clarity and maintainability, with variations such as:

• with text
• with text and icon (left / right / left & right)
• with only icon
• with status
• for full-width
• for disabled type

HTML code:

Link

Button

Primary

Button text
Button text
Button text
Button text


Secondary

Button text
Button text
Button text
Button text


Tertiary

Button text
Button text
Button text
Button text


Width modifier
Categories
Categories
Categories

Disabled
Button text
Button text
Button text

Status

CSS code:

/* ---------------------------------------------------------- */
/*                     Snippflow Button                       */
/* ---------------------------------------------------------- */

.sf-button {
    --sf-button-gap: 8px;
    --sf-button-padding-top: 12px;
    --sf-button-padding-bottom: 12px;
    --sf-button-padding-left: 16px;
    --sf-button-padding-right: 16px;
    --sf-button-border-radius: 8px;
    --sf-button-box-shadow: 0px 1px 2px 0px rgba(16, 24, 40, 0.05);

    --sf-button-primary-color: #fff;
    --sf-button-primary-bg: #46a787;
    --sf-button-primary-border: #3f9b7d;
    --sf-button-primary-hover-color: #fff;
    --sf-button-primary-hover-bg: #3c9376;
    --sf-button-primary-hover-border: #378c70;

    --sf-button-secondary-color: #121924;
    --sf-button-secondary-bg: #F8F8F9;
    --sf-button-secondary-border: #cbd5e1;
    --sf-button-secondary-hover-color: #121924;
    --sf-button-secondary-hover-bg: #fff;
    --sf-button-secondary-hover-border: #cbd5e1;

    --sf-button-tertiary-color: #121924;
    --sf-button-tertiary-bg: transparent;
    --sf-button-tertiary-border: transparent;
    --sf-button-tertiary-hover-color: #121924;
    --sf-button-tertiary-hover-bg: #e0e5ea;
    --sf-button-tertiary-hover-border: transparent;

    --sf-button-tertiary-status: #c82020;
}

a.sf-button,
input[type="submit"].sf-button,
input[type="reset"].sf-button,
input[type="button"].sf-button,
button.sf-button {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: var(--sf-button-gap);
    position: relative;
    box-sizing: border-box;
    font-size: inherit;
    font-weight: 500;
    line-height: 1;
    padding: var(--sf-button-padding-top) var(--sf-button-padding-right) var(--sf-button-padding-bottom) var(--sf-button-padding-left);
    border: 1px solid;
    border-radius: var(--sf-button-border-radius);
    white-space: nowrap;
    outline: unset;
    text-decoration: none;
    cursor: pointer;
    transition: all 0.3s ease-in-out;

    &[aria-expanded="true"],
    &:hover {
        text-decoration: none;
    }

    /* Is fit  (100%)*/
    &.is-fit {
        width: 100%;
    }

    /*   Is fit margin */
    &   .is-fit {
        margin-top: 10px; /* btn under other is-fit btm */
    }

    /* Has status */
    &.has-status {
        :after {
            content: "";
            display: block;
            width: 8px;
            height: 8px;
            border-radius: 100%;
            background-color: var(--sf-button-tertiary-status);
            position: absolute;
            right: 5px;
            top: 5px;
            animation: sp-status-pulse 1s infinite ease-in-out alternate;
        }
    }

    /* Is disabled */
    &.disabled,
    &:disabled,
    &[aria-disabled="true"] {
        cursor: default;
        filter: saturate(0%);
        opacity: .7;
        background: transparent;
        transform: none;
        box-shadow: none;
        outline: none;

        &:hover {
            color: initial;
            pointer-events: none;
        }
    }

    /*  Icon */
     & > i {
        min-width: 18px;
        font-style: normal;
        text-align: center;
    }

    /* Has only icon */
    &.has-only-icon {
        padding: var(--sf-button-padding-top);
    }

    /* Primary button */
    &.is-primary {
        color: var(--sf-button-primary-color);
        background-color: var(--sf-button-primary-bg);
        border-color: var(--sf-button-primary-border);
        box-shadow: var(--sf-button-box-shadow);

        &:hover:not(:disabled) {
            color: var(--sf-button-primary-color);
            background-color: var(--sf-button-primary-hover-bg);
            border-color: var(--sf-button-primary-hover-border);
        }
    }

    /* Secondary button */
    &.is-secondary {
        color: var(--sf-button-secondary-color);
        background-color: var(--sf-button-secondary-bg);
        border-color: var(--sf-button-secondary-border);
        box-shadow: var(--sf-button-box-shadow);

        &:hover:not(:disabled) {
            color: var(--sf-button-secondary-color);
            background-color: var(--sf-button-secondary-hover-bg);
            border-color: var(--sf-button-secondary-hover-border);
        }
    }

    /* Tertiary button */
    &.is-tertiary {
        color: var(--sf-button-tertiary-color);
        background-color: var(--sf-button-tertiary-bg);
        border-color: var(--sf-button-tertiary-border);

        &:hover:not(:disabled) {
            color: var(--sf-button-tertiary-color);
            background-color: var(--sf-button-tertiary-hover-bg);
            border-color: var(--sf-button-tertiary-hover-border);
        }
    }

}

@keyframes sp-status-pulse {
    from { transform: scale(0.8); }
    to { transform: scale(1.1); }
}

See the following Codepen for a demo:

PS. I hope it will be useful ;)

Full article: https://snippflow.com/snippet/flexbox-button-with-3-styles-and-variations/
CSS Snippets