html {
  background-color: black;
}

body {
  background-image: linear-gradient(#000000,#000000)
  font-size: 100%
}

h1 {
  color: #FFFFFF;
  text-align: center;

}


h2 {
  color: #FFFFFF;
  text-align: center;

}

h3 {
  color: #FFFFFF;
  text-align: center;
  font-size: 200%
}


p {
  font-family: noto-sans;
  font-size: 1em;
  color: #FFFFFF;
  text-align: center;
  padding-left: 25%;
  padding-right: 25%;
  padding-top: 1.5%;
  padding-bottom: 1.5%;

}

#Imaginaario {cursor: pointer;

  display: block;
  margin-left: auto;
  margin-right: auto;
}

#Main-Heading {

  font-family: Arvo, Garamond, serif;

  font-size: 72px;

  color: white;
}



#Eka-osio {

  background-color: #000000;
}h2 {
  color: #FFFFFF;
  text-align: center;
  image-align: center;
}

a {
  color: white;
}



#Toka-osio {

  background-color: #000000;
}

p {
  font-family: noto-sans;
  font-size: 1em;
  color: #FFFFFF;
  text-align: center;
  padding-left: 25%;
  padding-right: 25%;
  padding-top: 1.5%;
  padding-bottom: 1.5%;

}

#Kolmas-osio {

  background-color: ##e1a7cc;
}
div {
  padding-left: 0%;
  padding-right: 0%;
  padding-top: 0%;
  padding-bottom: 0%;
}
<style>
.button {
  border: none;
  color: white;
  padding: 16px 32px;
  padding-bottom: 32px;
  text-align: center;
  text-decoration: none;
  display: inline-block;
  font-size: 14px;
  margin: 4px 2px;
  transition-duration: 0.4s;
  cursor: pointer;
}

.button1 {
  background-color: white;
  color: black;
  border: 2px solid #04AA6D;
}

.button1:hover {
  background-color: #04AA6D;
  color: white;
}

.button2 {
  background-color: white;
  color: black;
  border: 2px solid #008CBA;
}

.button2:hover {
  background-color: #008CBA;
  color: white;
}

p {
  font-family: noto-sans;
  font-size: 20px;
  color: #FFFFFF;
  text-align: center;
  padding-left: 25%;
  padding-right: 25%;
  padding-top: 0.5%;
  padding-bottom: 0.5%;

}


form {
  font-family: noto-sans;
  font-size: 1em;
  color: white;
  border-style: solid;
  border-radius: 20px;
  border-color: white;
  border-width: thin;
}

.formi {
  font-color:
}

.password-container {
  max-width: 60%;
  margin: auto;
  background: black;
  padding: 30px;
  border-radius: 10px;
  box-shadow: 0 2px 10px rgba(0,0,0,0.1);
  text-align: center;
}

.password-input {
  width: 100%;
  padding: 12px;
  margin: 15px 0;
  border: 2px solid #ddd;
  border-radius: 5px;
  font-size: 1em;
  box-sizing: border-box;
}

.password-button {
  background-color: #8B4513;
  color: white;
  padding: 12px 30px;
  border: 1px;
  border-radius: 5px;
  cursor: pointer;
  font-size: 1em;
}

.password-button:hover {
  background-color: #654321;
}

.error-message {
  color: #d32f2f;
  margin-top: 1em;
  display: none;
}

/* This is the key rule - hide main content initially */
.main-content {
  display: none;
  width: 100%;
}