OS Details

Huawei Y9s has been launched in November 2019.
Huawei Y9s have Android 9.0 (Pie) ; EMUI 9.1

Screen Dimensions

Huawei Y9s screen size is 6.59 inch with ~ 84.7% body ratio of actual device size. Physical dimensions for Huawei Y9s device is 6.42 x 3.04 x 0.35 INCH or ( 163.1 x 77.2 x 8.8 MM).

Displaying of Units are in this order "Height x Width x Thickness"

Screen Pixel Density and CSS Pixel Ratio

"Pixel" is smallest unit/element of any display.

The total number of pixels that fit into an inch is referred to as "Screen Density" or "Pixel Density" and it measured as "Pixels Per Inch".
Pixel Desnsity have limits to display Pixels Per Inch depends on different screen sizes. When number of pixels per inch increases than it's screen-size limit, the Display resolution will increase but actual device width/height in pixels remain same. Actual device pixels are known as Device Independent Pixels or CSS Pixel Ratio.

Huawei Y9s resolution is 1080 x 2340 ^PX with ~ 391 pixel desnsity.
Huawei Y9s viewport size is 360 x 780 ^PX with ~ 130 actual pixel density, which means it have 3.0 xxhdpi display pixel density.

Screen Resolution and Viewport

The sum of pixels which are displaying on a device is called as "Screen Resolution". and sum of actual pixels of any device is reffered to as "Viewport".

Huawei Y9s have 6.59" physical screen size and its resolution is about 1080 x 2340 Pixels with approximately 391 PPI pixel density. Huawei Y9s has viewport size 360 x 780 Pixels and its pixel ratio is about 3.0.

For better understanding screen actual sizes, viewport sizes, display resolution and about their density click here.

CSS Media Queries

Targeted css media queries will help developers to write styles specifically for Huawei Y9s. Here are details:

Huawei Y9s Media Queries (In terms of Mobile only)

@media only screen and (min-width: 360px) and (max-width: 767px) { /* Your Styles... */ }

Huawei Y9s Min-Width Media Queries

@media only screen and (min-width: 360px) { /* Your Styles... */ }

Huawei Y9s Min-Height Media Queries

@media only screen and (min-height: 780px) { /* Your Styles... */ }

Huawei Y9s Landscape Media Queries

@media only screen and (min-width: 780px) and (orientation: landscape) { /* Your Styles... */ }

Huawei Y9s Portrait Media Queries

@media only screen and (min-width: 360px) and (orientation: portrait) { /* Your Styles... */ }

Huawei Y9s Device Width Media Queries

@media only screen and (min-device-width: 360px) and (orientation: portrait) { /* Your Styles... */ }
@media only screen and (min-device-width: 780px) and (orientation: landscape) { /* Your Styles... */ }

Huawei Y9s Retina Media Queries

@media
  only screen and (-webkit-min-device-pixel-ratio: 3.0),
  only screen and (   min--moz-device-pixel-ratio: 3.0),
  only screen and (     -o-min-device-pixel-ratio: 3.0/1),
  only screen and (        min-device-pixel-ratio: 3.0),
  only screen and (                min-resolution: 391dpi),
  only screen and (                min-resolution: 3.0dppx) { 
    /* Retina styles here */
} 
                                

Retina is actually based upon device pixel ratio. Devices mostly have 2x or 3x display so you can use general retina media queries to display high resolution content on all kind of devices. Retina 2x and Retina 3x media queries given below:

Retina 2x Media Query (for all 2x resolution supported devices)

@media
  only screen and (-webkit-min-device-pixel-ratio: 2),
  only screen and (   min--moz-device-pixel-ratio: 2),
  only screen and (     -o-min-device-pixel-ratio: 2/1),
  only screen and (        min-device-pixel-ratio: 2),
  only screen and (                min-resolution: 192dpi),
  only screen and (                min-resolution: 2dppx) { 
    /* Retina styles here */
}
                                

Retina 3x Media Query (for all 3x resolution supported devices)

@media
  only screen and (-webkit-min-device-pixel-ratio: 3),
  only screen and (   min--moz-device-pixel-ratio: 3),
  only screen and (     -o-min-device-pixel-ratio: 3/1),
  only screen and (        min-device-pixel-ratio: 3),
  only screen and (                min-resolution: 384dpi),
  only screen and (                min-resolution: 3dppx) { 
    /* Retina styles here */
}
                                

Huawei Y9s Specifications

• Launch Date November 2019
• Android 9.0
• Physical Screen Size 6.59 INCH
• Resolution 1080 x 2340 PX
• Viewport Size 360 x 780 PX
• Pixel Density 391 PPI
• Device-Independent Pixels 130 PPI
• Pixel Ratio 3.0 xxhdpi
• Width 1080 PX
• Height 2340 PX
• Device Width 360 PX
• Device Height 780 PX
• Dimensions 163.1 x 77.2 x 8.8 mm (6.42 x 3.04 x 0.35 in)
• Weight 206 g - 7.27 oz