Several methods for js to determine the horizontal and vertical screen viewport detection of mobile terminals

// Get the visual viewport size (including vertical scroll bar)
let iw = window.innerWidth,
 ih = window.innerHeight;
console.log(iw, ih);

// Get the visual viewport size (the size of the content area, including the sidebar, window chrome, and borders for resizing the window)
let ow = window.outerWidth,
 oh = window.outerHeight;
console.log(ow, oh);

// Get the ideal viewport size of the screen, fixed value (screen resolution size)
let sw = window.screen.width,
 sh = window.screen.height;
console.log(sw, sh);

// Get the size of the browser's available window (including padding, but excluding vertical scroll bars, borders, and margins)
let aw = window.screen.availWidth,
 ah = window.screen.availHeight;
console.log(aw, ah);

// Including padding, scrollbars, borders and margins let dow = document.documentElement.offsetWidth,
 doh = document.documentElement.offsetHeight;
console.log(dow, doh);

// The minimum width and height required to fit all content in the viewport without using scrollbars let dsW = document.documentElement.scrollWidth,
 dsH = document.documentElement.scrollHeight;
console.log(dsW, dsH);

// Includes the element's padding, but not borders, margins, or vertical scrollbars let cw = document.documentElement.clientWidth,
 ch = document.documentElement.clientHeight;
console.log(cw, ch);

// window.orientation: Get the screen rotation direction window.addEventListener('resize', () => {
 // Normal orientation or screen rotated 180 degrees if (window.orientation === 180 || window.orientation === 0) {
  console.log('vertical screen')
 }

 // The screen rotates 90 degrees clockwise or 90 degrees counterclockwise if (window.orientation === 90 || window.orientation === -90) {
  console.log('horizontal screen')
 }
});

/*css detection of horizontal and vertical screen*/
@media screen and (orientation:portrait) {

 /* Vertical screen */
 #app {
  width: 100vw;
  height: 100vh;
  background: red;
 }
}

@media screen and (orientation:landscape) {

 /* Horizontal screen */
 #app {
  width: 50vw;
  height: 100vh;
  background: green;
 }
}

<meta name="viewport" content="width=device-width,initial-scale=1,minimum-scale=1,maximum-scale=1,user-scalable=no" />

<meta name="viewport" content="viewport-fit=cover" />

/* When using the bottom fixed navigation bar, we need to set the padding value for them: */
body {
 padding-bottom: constant(safe-area-inset-bottom);
 padding-bottom: env(safe-area-inset-bottom);
}