Webleb - HTML UI Elements -

<!DOCTYPE html>
<html>
<head>
    <title>Tela de login</title>
    <style>
        canvas {
            position: absolute;
            top: 0;
            left: 0;
        }
    </style>
</head>
<body>
    <canvas id="rainfall"></canvas>

// Set canvas size to match window size
        canvas.width = window.innerWidth;
        canvas.height = window.innerHeight;

// Create an array to store the raindrops
        const raindrops = [];

// Function to create a new raindrop
        function createRaindrop() {
            const x = Math.random() * canvas.width;
            const y = -5;
            const speed = Math.random() * 5 + 2;
            const length = Math.random() * 20 + 10;

raindrops.push({ x, y, speed, length });
        }

// Function to update the raindrops' positions
        function updateRaindrops() {
            for (let i = 0; i < raindrops.length; i++) {
                const raindrop = raindrops[i];

raindrop.y += raindrop.speed;

if (raindrop.y > canvas.height) {
                    raindrops.splice(i, 1);
                    i--;
                }
            }
        }

// Function to draw the raindrops
        function drawRaindrops() {
            ctx.clearRect(0, 0, canvas.width, canvas.height);

ctx.strokeStyle = 'white';
            ctx.lineWidth = 2;

for (let i = 0; i < raindrops.length; i++) {
                const raindrop = raindrops[i];

ctx.beginPath();
                ctx.moveTo(raindrop.x, raindrop.y);
                ctx.lineTo(raindrop.x, raindrop.y + raindrop.length);
                ctx.stroke();
            }
        }

// Function to animate the raindrops
        function animate() {
            createRaindrop();
            updateRaindrops();
            drawRaindrops();

requestAnimationFrame(animate);
        }

// Start the animation
        animate();
    </script>

</body>
</html>

@import url(https://fonts.googleapis.com/css?family=Poppins:300);
html {
 height: 100%;
}
body{
 margin:0;
 padding:0;
 font-family: sans-serif;
 background: linear-gradient(#30142b, #2772a1);
}
.login-page {
  width: 400px;
  padding: 8% 0 0;
  margin: auto;
}
.form {
  position: relative;
  z-index: 1;
  text-align: center;
  position: absolute;
  top: 50%;
  left: 50%;
  width: 400px;
  padding: 40px;
  transform: translate(-50%, -50%);
  background: rgba(0,0,0,.5);
  box-sizing: border-box;
  box-shadow: 0 15px 25px rgba(0,0,0,.6);
  border-radius: 10px;
}
.form input {
 width: 100%;
 padding: 10px 0;
 font-size: 13px;
 color: #fff;
 margin-bottom: 30px;
 border: none;
 border-bottom: 1px solid #fff;
 outline: none;
 background: transparent;
  
}
h2{
 color:white;
}

.form .message {
  margin: 15px 0 0;
  color: #b3b3b3;
  font-size: 12px;
}
.form .message a {
  color: #289bb8;
  text-decoration: none;
}
.form .register-form {
  display: none;
}
.btn {
  position: relative;
  display: inline-block;
  padding: 10px 20px;
  color: #289bb8;
  font-size: 16px;
  text-decoration: none;
  overflow: hidden;
  transition: .5s;
  margin-top: 15px;
  letter-spacing: 2px
}
.btn:hover {
  background: #289bb8;
  color: #fff;
  border-radius: 5px;
  box-shadow: 0 0 5px #289bb8,
              0 0 25px #289bb8,
              0 0 50px #289bb8,
              0 0 100px #289bb8;
}

.btn span {
  position: absolute;
  display: block;
}

.btn span:nth-child(1) {
  top: 0;
  left: -100%;
  width: 100%;
  height: 2px;
  background: linear-gradient(90deg, transparent, #289bb8);
  animation: btn-anim1 1s linear infinite;
}

@keyframes btn-anim1 {
  0% {
    left: -100%;
  }
  50%,100% {
    left: 100%;
  }
}

.btn span:nth-child(2) {
  top: -100%;
  right: 0;
  width: 2px;
  height: 100%;
  background: linear-gradient(180deg, transparent, #289bb8);
  animation: btn-anim2 1s linear infinite;
  animation-delay: .25s
}

@keyframes btn-anim2 {
  0% {
    top: -100%;
  }
  50%,100% {
    top: 100%;
  }
}

.btn span:nth-child(3) {
  bottom: 0;
  right: -100%;
  width: 100%;
  height: 2px;
  background: linear-gradient(270deg, transparent, #289bb8);
  animation: btn-anim3 1s linear infinite;
  animation-delay: .5s
}

@keyframes btn-anim3 {
  0% {
    right: -100%;
  }
  50%,100% {
    right: 100%;
  }
}

.btn span:nth-child(4) {
  bottom: -100%;
  left: 0;
  width: 2px;
  height: 100%;
  background: linear-gradient(360deg, transparent, #289bb8);
  animation: btn-anim4 1s linear infinite;
  animation-delay: .75s
}

@keyframes btn-anim4 {
  0% {
    bottom: -100%;
  }
  50%,100% {
    bottom: 100%;
  }
}

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