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HTML 

              
                <canvas id="canvas"></canvas>
<div id="infoEl">TRAVELER</div>
<div id="infoEl2">The journey is the adventure...</div>
!

CSS 

              
                body {
  background: black;
}
canvas {
  position: absolute;
  top: 0px;
  left: 0px;
  background: black;
  border-top: 1px solid white;
  border-bottom: 1px solid white;
}
.compressed {
  top: 34%;
}
#infoEl {
  position: absolute;
  bottom: 66%;
  left: 0px;
  width: 100%;
  font-family: arial;
  color: #fff;
  font-size: xx-large;
  letter-spacing: 0.75em;
  text-align: center;
}
#infoEl2 {
  position: absolute;
  top: 66%;
  left: 0px;
  width: 100%;
  font-family: arial;
  color: #fff;
  font-size: small;
  letter-spacing: 0.5em;
  text-align: center;
}
.hide {
  display: none;
}
!

JS 

              
                
var W = canvas.width = innerWidth, W2 = W / 2;   
var H = canvas.height = innerHeight, H2 = H / 2; 
setTimeout(()=>{
const ctx = canvas.getContext("2d");
const assign = (obj, ...objs) => Object.assign(obj, ...objs);
const clamp   = (v, min = 0, max = 1) =>  Math.max(min, Math.min(max, v));
const rand = (m, M) => Math.random() * (M - m) + m;
const randItem = (array) => array[(Math.random() * array.length) | 0];
const eCurve   = (v, p = 2, vp) =>  v < 0 ? 0 : v > 1 ? 1 : (vp = v ** p) / (vp + (1 - v) ** p);
const fCurve   = (v) =>  v < 0 ? 0 : v > 1 ? 1 : v;
const iCurve   = (v, p = 2) =>  v < 0 ? 0 : v > 1 ? 1 : v ** p;
const RGB = (r, g, b, a = 255) => ({r, g, b, a});
const hex8 = v => (clamp(v, 0, 255) | 0).toString(16).padStart(2, "0");
const RGB2CSS = (rgb) => "#" + hex8(rgb.r) + hex8(rgb.g) + hex8(rgb.b) + hex8(rgb?.a ?? 255) 
const lerpRGB = (a, b, v, res = {}) => (
    res.r = (b.r - a.r) * v + a.r,
    res.g = (b.g - a.g) * v + a.g,
    res.b = (b.b - a.b) * v + a.b,
    res.a = (b.a - a.a) * v + a.a,
    res    
);  
  
  
const colGrad = (top, bot, rgbT, rgbB) => {
    const g = ctx.createLinearGradient(0, H * top, 0, H * bot);
    g.addColorStop(0, RGB2CSS(rgbT));
    g.addColorStop(1, RGB2CSS(rgbB));
    return g;
}
const colRadGrad = (x, y, rad, rgbT, rgbB, curve, curveMod) => {
    var i = 0;
    const r = (x * x + (H - y) ** 2) ** 0.5
    const g = ctx.createRadialGradient(x, y, rad, x, y, r);
    g.addColorStop(0, RGB2CSS(rgbT));
    if (curve) {
        const step = 1 / (r / 8);
        i = step;
        while (i < 1) {
            g.addColorStop(curve(i, curveMod), RGB2CSS(lerpRGB(rgbT, rgbB, i)));
            i+= step;
        }
    }
    g.addColorStop(1, RGB2CSS(rgbB));
    return g;
}    
const BGCol = RGB(100, 200, 255);
const BGColA = RGB(25, 20, 5);
const FGCol = RGB(60, 180, 80);
const mistCol = RGB(200, 220, 250);
const sunCol = RGB(255, 240, 230);
const sunColA = RGB(255, 240, 230, 255);
const sunColB = RGB(255, 240, 230, 0);
const BGColor = colGrad(0, 1,BGCol, mistCol);
const base = H;
const steps = 100;
const levels = (scale, itemOdds = 0, maxY = base, minY = base / 2, dym = -1, dyM = -10, dymSet = 1, dyMSet = 10, cDir = 20, cDirSet = 20) => ({
    scale, itemOdds, maxY, minY, dym, dyM, dymSet, dyMSet, cDir, cDirSet
})
const land = {
    get levels() { return [] },
    get items() { return [] },
    y: base,
    /*maxY: base,
    minY: base / 2,
    dym: -1,
    dyM: -10,
    dymSet: 1,
    dyMSet: 10,
    cDir: 20,
    cDirSet: 20,*/
    get current() { return  levels(1) },
    get levelSets() { return [] },
    levelChangeOdds: 1 / 100,
    size: 100, 
    color: "#0F0",
    curve: eCurve,
    curveData: 2,
    pos: 0,

    init() {
        this.levelSets.push({...this.current});
        var i = 0
        this.y = rand(this.current.minY, this.current.maxY);
        while (i < this.size) {
            this.levels.push(this.next());
            this.items.push(0);
            i++;
            
        }
        return this;
    },
    next() {
        const C = this.current;
        if (this.y < C.minY) {
            this.y += Math.abs(rand(C.dym, C.dyM));
            return this.y;
            
        }
        if (this.y > C.maxY) {
            this.y -= Math.abs(rand(C.dym, C.dyM));
            return this.y;
            
        }        
        const range = C.maxY - C.minY
        this.y += rand(C.dym, C.dyM);
        this.dyM += rand(-1,1);
        this.cDir -= 1;
        if (this.y < C.minY) {
            C.dym = rand(0, C.dymSet);
            C.dyM = rand(C.dym, C.dyMSet);
            this.y = C.minY + 1;
            C.cDir = C.cDirSet;
        } else if (this.y > C.maxY) {
            C.dym = -rand(0, C.dymSet);
            C.dyM = -rand(C.dym, C.dyMSet);
            this.y = C.maxY - 1;
            C.cDir = C.cDirSet;
        } else if (C.cDir <= 0 || Math.random() < 1 / C.cDir) {
            C.cDir = C.cDirSet;
            const s = Math.sign(-C.dyM);
            C.dym = rand(0, C.dymSet) * s;
            C.dyM = rand(C.dym, C.dyMSet) * s;                
        }
        return  this.curve((this.y - C.minY) / range, this.curveData) * range + C.minY;
        //return this.y;
    },
    update() {
        const C = this.current;
        const y = this.levels[this.size -1] = this.next();
        if (y > (C.minY + C.maxY) / 2) {
            this.items[this.size -1] = Math.random() < C.itemOdds ? rand(1, 2) : 0;
        } else {
            this.items[this.size -1] = 0;
        }
        this.pos += 1;
        if (Math.random() < this.levelChangeOdds) {
            assign(C,randItem(this.levelSets));
        }
    },
    draw(ctx) {
        var pp = this.pos;
        ctx.fillStyle = this.color;
        const step = sW / (this.size-2);
        const l = this.levels;
        const t = this.items;
        var i = 0;
        ctx.beginPath();
        ctx.lineTo(sW, sH);
        ctx.lineTo(0, sH);
        while (i < this.size - 1) {
            const tt = t[i];
            const y = l[i++];
            const x = i * step;            
            if (tt) {
                addTree(ctx, x, y, this.current.scale, tt, pp);
                
            } else {
                ctx.lineTo(x, y);
            }
            l[i-1] = l[i];
            t[i-1] = t[i];
            pp++;
        }
        ctx.closePath();
        ctx.fill();
        
    }
}
function addTree(ctx, x, y, scale, val, type) {
    if (type % 2) {
        const tw = 4 * scale;
        const tww = 14 * scale * val;
        const th = 10 * scale;
        const thh = 40 * scale * val;
        ctx.lineTo(x - tww, y - th + tw);
        ctx.lineTo(x, y - thh);
        
        ctx.lineTo(x + tww, y - th + tw);
       
    } else {
        const tw = 4 * scale;
        const tww = 14 * scale * val;
        const th = 20 * scale;
        const thh = 80 * scale * val;        
        ctx.lineTo(x - tw, y);
        ctx.lineTo(x - tw, y - th);
        ctx.lineTo(x - tww, y - th + tw);
        ctx.lineTo(x, y - thh);
        
        ctx.lineTo(x + tww, y - th + tw);
        ctx.lineTo(x + tw, y - th);
        ctx.lineTo(x + tw, y);    
    }
    
}
//(maxY, minY, dym, dyM, dymSet, dyMSet, cDir, cDirSet)
const U = undefined;
const points = W / 4 | 0;
const lands = [({
        ...land, 
        color: colGrad(0.1, 1,lerpRGB(BGColA, lerpRGB(BGCol, FGCol, 0.2), 0.7), mistCol),
        current: levels(0.4, 0, base * 0.5, base * 0.1, U, U, 5, 10, U, 40),
        size: points, 
        curve: iCurve,
        curveData: 1/2, 
        
    }).init(),
    ({
        ...land, 
        color: colGrad(0.4, 1,lerpRGB(BGColA, lerpRGB(BGCol, FGCol, 0.4), 0.6), mistCol),
        current: levels(0.475, 0, base * 0.6, base * 0.4, U, U, 2, 4, U, 50),
        levelSets: [
            levels(0.475, 0, base * 0.7, base * 0.55, U, U, 2, 10, U, 4)
        ],
        size: points * 0.9 | 0,        
    }).init(),
    ({
        ...land, 
        color: colGrad(0.5, 1.2,lerpRGB(BGColA, lerpRGB(BGCol, FGCol, 0.6), 0.5), mistCol),
        current: levels(0.25, 0.1, base * 0.75, base * 0.5, U, U, 2, 5, U, 4),
        size: points * 0.8 | 0,
        curve: iCurve,
        curveData: 1/2, 
    }).init(),
    ({
        ...land, 
        color: colGrad(0.6, 1.5,lerpRGB(BGColA, lerpRGB(BGCol, FGCol, 0.8), 0.4), mistCol),
        current: levels(0.5 , 0.05,base * 0.8, base * 0.6, U, U, 2, 7, U, 3),
        levelSets: [
            levels(0.5 , 0.2, base * 0.85, base * 0.7, U, U, 1, 3, U, 13),
            levels(0.5 , 0.2, base * 0.9, base * 0.74, U, U, 1, 3, U, 13),
            levels(0.5 , 0.2, base * 0.95, base * 0.78, U, U, 1, 3, U, 13),
        ],
        size: points * 0.7 | 0,
        curve: fCurve,
        
    }).init() ,
    ({
        ...land, 
        color: colGrad(0.8, 2,lerpRGB(BGColA, lerpRGB(BGCol, FGCol, 1), 0.2), mistCol),
        current: levels(1, 0.025, base * 0.9, base * 0.8, U, U, 1, 6, U, 40),
        size: points * 0.6 | 0,
        curve: fCurve,
        
    }).init(),   
];
const Sun = ({
    x: W * 0.8,
    y: H * 0.2,
    col: RGB2CSS(sunCol),
    draw(ctx) {
        ctx.fillStyle = this.bgCol;
        ctx.fillRect(0, 0, sW, sH);        
        ctx.fillStyle = this.col;
        ctx.beginPath();
        ctx.arc(this.x, this.y, 20, 0, Math.TAU);
        ctx.fill()
    },
    init() {
        this.bgCol = colRadGrad(this.x, this.y, 20, sunColA, sunColB, iCurve, 2.5);
        return this;
    }
    
}).init();

requestAnimationFrame(renderLoop);
  
  
const sW = W, sH = H;
var sX = 1, sY = 1;
const squashH = H * 0.3 | 0;
  
function renderLoop() {
    if (W !== innerWidth || H !== squashH) {
        W2 = (W = canvas.width = innerWidth) / 2;
        H2 = (H = canvas.height = squashH) / 2;
        sX = (W + 40) / sW;
        sY = H / sH;
        canvas.classList.add("compressed");
    }  
    ctx.setTransform(sX,0,0,sY,-20,0);
    ctx.fillStyle = BGColor;
    ctx.fillRect(0, 0, sW, sH);
    Sun.draw(ctx);
    for (const l of lands) {
        l.update();
        l.draw(ctx);
    }
    requestAnimationFrame(renderLoop);
}  
  
}, 1000);
!
999px

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