import { Meta, Canvas, Story } from '@storybook/addon-docs';

<Meta title="Foundations / Shadow" />

# Shadow

Shadows convey elevation of elements on a surface

## Size

There are 4 different sizes of shadow in MetaMask

<div
  style={{
    display: 'grid',
    gap: '32px',
    gridTemplateColumns: 'repeat(auto-fill, 200px)',
    marginTop: 16,
    marginBottom: 16,
  }}
>
  <div
    style={{
      height: 100,
      backgroundColor: 'var(--color-background-default)',
      boxShadow: 'var(--shadow-size-xs) var(--color-shadow-default',
      borderRadius: '4px',
      display: 'grid',
      alignContent: 'center',
      justifyContent: 'center',
      color: 'var(--color-text-default)',
    }}
  >
    <span>XS</span>
  </div>
  <div
    style={{
      height: 100,
      backgroundColor: 'var(--color-background-default)',
      boxShadow: 'var(--shadow-size-sm) var(--color-shadow-default',
      borderRadius: '4px',
      display: 'grid',
      alignContent: 'center',
      justifyContent: 'center',
      color: 'var(--color-text-default)',
    }}
  >
    <span>SM</span>
  </div>
  <div
    style={{
      height: 100,
      backgroundColor: 'var(--color-background-default)',
      boxShadow: 'var(--shadow-size-md) var(--color-shadow-default',
      borderRadius: '4px',
      display: 'grid',
      alignContent: 'center',
      justifyContent: 'center',
      color: 'var(--color-text-default)',
    }}
  >
    <span>MD</span>
  </div>
  <div
    style={{
      height: 100,
      backgroundColor: 'var(--color-background-default)',
      boxShadow: 'var(--shadow-size-lg) var(--color-shadow-default',
      borderRadius: '4px',
      display: 'grid',
      alignContent: 'center',
      justifyContent: 'center',
      color: 'var(--color-text-default)',
    }}
  >
    <span>LG</span>
  </div>
</div>

| Size   | CSS                     |
| ------ | ----------------------- |
| **XS** | `var(--shadow-size-xs)` |
| **SM** | `var(--shadow-size-sm)` |
| **MD** | `var(--shadow-size-md)` |
| **LG** | `var(--shadow-size-lg)` |

## Color

As well as the neutral colors for shadow 2 other colors exist that are used for the primary and error/danger button hover states

<div
  style={{
    display: 'grid',
    gap: '32px',
    gridTemplateColumns: 'repeat(auto-fill, 200px)',
    marginTop: 16,
    marginBottom: 16,
  }}
>
  <div
    style={{
      height: 100,
      backgroundColor: 'var(--color-background-default)',
      boxShadow: 'var(--shadow-size-lg) var(--color-shadow-default)',
      borderRadius: '4px',
      display: 'grid',
      alignContent: 'center',
      justifyContent: 'center',
      color: 'var(--color-text-default)',
    }}
  >
    <span>Default</span>
  </div>
  <div
    style={{
      height: 100,
      backgroundColor: 'var(--color-primary-default)',
      boxShadow: 'var(--shadow-size-lg) var(--color-shadow-primary)',
      borderRadius: '4px',
      display: 'grid',
      alignContent: 'center',
      justifyContent: 'center',
      color: 'var(--color-primary-inverse)',
    }}
  >
    <span>Primary</span>
  </div>
  <div
    style={{
      height: 100,
      backgroundColor: 'var(--color-error-default)',
      boxShadow: 'var(--shadow-size-lg) var(--color-shadow-error)',
      borderRadius: '4px',
      display: 'grid',
      alignContent: 'center',
      justifyContent: 'center',
      color: 'var(--color-error-inverse)',
    }}
  >
    <span>Error/Danger</span>
  </div>
</div>

| Color       | CSS                           |
| ----------- | ----------------------------- |
| **neutral** | `var(--color-shadow-default)` |
| **primary** | `var(--color-shadow-primary)` |
| **danger**  | `var(--color-shadow-error)`   |

## Example usage

Using both size and color tokens, different shadows can be applied to components

<div>
  <div
    style={{
      display: 'grid',
      gap: '32px',
      gridTemplateColumns: 'repeat(auto-fill, 200px)',
      marginBottom: '64px',
    }}
  >
    <div
      style={{
        borderRadius: '4px',
        display: 'grid',
        alignContent: 'center',
        justifyContent: 'center',
        height: 100,
        textAlign: 'center',
        boxShadow: 'var(--shadow-size-xs) var(--color-shadow-default)',
        color: 'var(--color-text-default)',
      }}
    >
      <span>Card</span>
    </div>
    <div
      style={{
        borderRadius: '4px',
        display: 'grid',
        alignContent: 'center',
        justifyContent: 'center',
        height: 100,
        textAlign: 'center',
        boxShadow: 'var(--shadow-size-sm) var(--color-shadow-default)',
        color: 'var(--color-text-default)',
      }}
    >
      <span>Dropdown</span>
    </div>
    <div
      style={{
        borderRadius: '4px',
        display: 'grid',
        alignContent: 'center',
        justifyContent: 'center',
        height: 100,
        textAlign: 'center',
        boxShadow: 'var(--shadow-size-md) var(--color-shadow-default)',
        color: 'var(--color-text-default)',
      }}
    >
      <span>Toast</span>
    </div>
    <div
      style={{
        borderRadius: '4px',
        display: 'grid',
        alignContent: 'center',
        justifyContent: 'center',
        height: 100,
        textAlign: 'center',
        boxShadow: 'var(--shadow-size-lg) var(--color-shadow-default)',
        color: 'var(--color-text-default)',
      }}
    >
      <span>Modal</span>
    </div>
  </div>
  <div
    style={{
      display: 'grid',
      gap: '32px',
      gridTemplateColumns: 'repeat(auto-fill, 200px)',
    }}
  >
    <div
      style={{
        borderRadius: '4px',
        display: 'grid',
        alignContent: 'center',
        justifyContent: 'center',
        height: 100,
        textAlign: 'center',
        boxShadow: 'var(--shadow-size-sm) var(--color-shadow-primary)',
        backgroundColor: 'var(--color-primary-default)',
        color: 'var(--color-primary-inverse)',
      }}
    >
      <span>Button Primary Hover</span>
    </div>
    <div
      style={{
        borderRadius: '4px',
        display: 'grid',
        alignContent: 'center',
        justifyContent: 'center',
        height: 100,
        textAlign: 'center',
        boxShadow: 'var(--shadow-size-sm) var(--color-shadow-error)',
        backgroundColor: 'var(--color-error-default)',
        color: 'var(--color-error-inverse)',
      }}
    >
      <span>Button Error/Danger Hover</span>
    </div>
  </div>
</div>

| Component                | JS                                                               | CSS |
| ------------------------ | ---------------------------------------------------------------- | --- |
| **Card**                 | `box-shadow: var(--shadow-size-xs) var(--color-shadow-default);` |
| **Dropdown**             | `box-shadow: var(--shadow-size-sm) var(--color-shadow-default);` |
| **Toast**                | `box-shadow: var(--shadow-size-md) var(--color-shadow-default);` |
| **Modal**                | `box-shadow: var(--shadow-size-lg) var(--color-shadow-default);` |
| **Button Primary Hover** | `box-shadow: var(--shadow-size-sm) var(--color-shadow-primary);` |
| **Button Danger Hover**  | `box-shadow: var(--shadow-size-sm) var(--color-shadow-error);`   |

## Takeaways

- Try to avoid using static media queries in your code
- Try to use the provided SCSS mixins

### ❌ Don't do this

Don't use static media queries in your code

```css
/**
* Don't do this
* Static box-shadows create inconsistency in elevation of elements
**/
.card {
  box-shadow: 0 0 5px 0 rgba(0, 0, 0, 0.2);
}
```

### ✅ Do this

Do use the provided shadow design token css variables

```css
.card {
  box-shadow: var(--shadow-size-xs) var(--color-shadow-default);
}
```

## References

- [Shadow design tokens](https://metamask.github.io/design-tokens/?path=/docs/shadows-shadows--shadow)
- [Figma light theme colors library(shadows page)](https://www.figma.com/file/kdFzEC7xzSNw7cXteqgzDW/%5BColor%5D-Light-Theme?node-id=753%3A719)(internal use only)
- [Figma dark theme colors library(shadows page)](https://www.figma.com/file/rLKsoqpjyoKauYnFDcBIbO/%5BColor%5D-Dark-Theme?node-id=522%3A1022)(internal use only)
