/* 1. Reset */
* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

/* 2. Body styling */
body {
  font-family: 'Segoe UI', sans-serif;
  line-height: 1.6;
  color: #333;
  background-color: #e0e0e0; /* light grey background */
  padding: 2rem;
}

/* 3. Headings */
h1, h2, h3 {
  margin-bottom: 0.5rem;
  color: #222; /* slightly darker grey for headings */
}
h1 {
  text-align: center;
  margin-bottom: 2rem;
}

/* 4. Buttons for toggles */
button.toggle {
  cursor: pointer;
  padding: 0.5rem 1rem;
  border: none;
  border-radius: 6px;
  background-color: #555; /* medium grey */
  color: white;
  font-size: 1rem;
  margin-bottom: 0.5rem;
  transition: background 0.2s ease;
}
button.toggle:hover {
  background-color: #333; /* darker grey on hover */
}

/* 5. Cipher container */
.cipher {
  margin-bottom: 1.5rem;
}

/* 6. Grid layout for tool + history */
.cipher-content {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 1rem;
  padding: 1rem;
  border: 1px solid #aaa; /* grey border */
  border-radius: 10px;
  background-color: #f0f0f0; /* very light grey background for content */
  transition: all 0.3s ease;
}

/* 7. Hide content when hidden */
.hidden {
  display: none; /* override grid */
}

/* 8. Inputs and textareas */
textarea, input {
  width: 100%;
  padding: 0.5rem;
  margin-bottom: 0.5rem;
  border: 1px solid #aaa; /* grey border */
  border-radius: 6px;
  font-family: inherit;
  font-size: 1rem;
  background-color: #eaeaea; /* soft grey input background */
  color: #222; /* dark grey text */
}

/* Input focus effect */
textarea:focus, input:focus {
  outline: none;
  border-color: #555; /* darker grey on focus */
  box-shadow: 0 0 5px rgba(0,0,0,0.1);
}

/* 9. Footer */
footer {
  text-align: center;
  padding: 1rem;
  background-color: #333; /* dark grey footer */
  color: white;
  margin-top: 2rem;
  border-radius: 6px;
}

/* 10. Responsive grid for mobile */
@media (max-width: 768px) {
  .cipher-content {
    grid-template-columns: 1fr; /* stack tool + history */
  }
}