:root {
  --bg: #ffffff;
  --fg: #000000;
  --gray-50: #fafafa;
  --gray-100: #f5f5f5;
  --gray-200: #eaeaea;
  --gray-800: #333333;
  --gray-900: #111111;
  --accents-1: #fafafa;
  --accents-2: #eaeaea;
  --accents-8: #000000;
  --border-color: #000;
  --border-width: 2px;
  --radius: 6px;
  --font-sans: -apple-system, BlinkMacSystemFont, "Segoe UI", "Roboto", "Oxygen", "Ubuntu", "Cantarell", "Fira Sans", "Droid Sans", "Helvetica Neue", sans-serif;
  --font-mono: Menlo, Monaco, Lucida Console, Liberation Mono, DejaVu Sans Mono, Bitstream Vera Sans Mono, Courier New, monospace;
}

@media (prefers-color-scheme: dark) {
  :root {
    --bg: #000000;
    --fg: #ffffff;
    --gray-50: #111111;
    --gray-100: #333333;
    --gray-200: #444444;
    --gray-800: #eaeaea;
    --gray-900: #fafafa;
    --accents-1: #111111;
    --accents-2: #333333;
    --accents-8: #ffffff;
    --border-color: #fff;
  }
}

* {
  box-sizing: border-box;
}

body {
  margin: 0;
  padding: 0;
  background-color: var(--bg);
  color: var(--fg);
  font-family: var(--font-sans);
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  min-height: 100vh;
  transition: background-color 0.2s, color 0.2s;
}

.container {
  width: 100%;
  max-width: 600px;
  padding: 2rem;
  border: var(--border-width) solid var(--border-color);
  border-radius: var(--radius);
  background: var(--bg);
}

h1 {
  font-size: 2rem;
  font-weight: 800;
  margin-top: 0;
  margin-bottom: 1.5rem;
  text-align: center;
  letter-spacing: -0.05rem;
}

p {
  line-height: 1.6;
  color: var(--gray-800);
  margin-bottom: 2rem;
  font-size: 1rem;
}

form {
  display: flex;
  gap: 1rem;
  margin-bottom: 2rem;
}

input[type="text"] {
  flex: 1;
  padding: 0.75rem 1rem;
  font-size: 1rem;
  background: var(--bg);
  color: var(--fg);
  border: var(--border-width) solid var(--border-color);
  border-radius: var(--radius);
  outline: none;
  font-family: var(--font-mono);
  transition: all 0.2s;
}

input[type="text"]:focus {
  box-shadow: 0 0 0 2px var(--fg);
}

button {
  padding: 0.75rem 1.5rem;
  font-size: 1rem;
  font-weight: 600;
  background: var(--fg);
  color: var(--bg);
  border: var(--border-width) solid var(--fg);
  border-radius: var(--radius);
  cursor: pointer;
  transition: all 0.2s;
  text-transform: uppercase;
  letter-spacing: 0.05rem;
}

button:hover {
  background: var(--bg);
  color: var(--fg);
}

#result {
  padding: 1.5rem;
  border: var(--border-width) solid var(--border-color);
  border-radius: var(--radius);
  font-family: var(--font-mono);
  font-size: 1.25rem;
  text-align: center;
  min-height: 80px;
  display: flex;
  align-items: center;
  justify-content: center;
  font-weight: bold;
}

.footer {
  margin-top: 1.5rem;
  font-size: 0.875rem;
  color: var(--gray-800);
  text-align: center;
  display: flex;
  justify-content: center;
  gap: 1rem;
}

.footer a {
  color: var(--fg);
  text-decoration: none;
  font-weight: 500;
  opacity: 0.6;
  transition: opacity 0.2s;
}

.footer a:hover {
  opacity: 1;
  text-decoration: underline;
}

@media (max-width: 640px) {
  .container {
    padding: 1.5rem;
    border-left: none;
    border-right: none;
    border-radius: 0;
    max-width: 100%;
  }

  h1 {
    font-size: 1.5rem;
  }

  p {
    font-size: 0.9rem;
  }

  form {
    flex-direction: column;
  }
  
  button {
    width: 100%;
    padding: 0.75rem;
  }

  input[type="text"] {
     font-size: 16px; /* Prevent zoom on iOS */
  }
  
  #result {
    font-size: 1rem;
    padding: 1rem;
  }
}