/* Reset */
* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}
body {
  font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
  background: #121212;
  color: #eee;
  line-height: 1.6;
  min-height: 100vh;
  display: flex;
  flex-direction: column;
}
header {
  background: #1f1f1f;
  padding: 2rem;
  text-align: center;
  box-shadow: 0 2px 5px rgba(0, 0, 0, 0.5);
}
header h1 {
  font-size: 2.5rem;
  margin-bottom: 0.3rem;
  color: #00ff99;
}
header .subtitle {
  font-size: 1.1rem;
  color: #bbb;
  max-width: 600px;
  margin: 0 auto;
}
main {
  flex-grow: 1;
  max-width: 900px;
  margin: 2rem auto;
  display: flex;
  gap: 2rem;
  flex-wrap: wrap;
}
section.box {
  background: #222;
  padding: 1.5rem;
  border-radius: 8px;
  box-shadow: 0 0 10px rgba(0, 255, 153, 0.1);
  flex: 1 1 400px;
}
section.box h2 {
  margin-bottom: 1rem;
  color: #00ff99;
}
label {
  display: block;
  margin-bottom: 0.3rem;
  font-weight: 600;
}
input[type='text'],
input[type='password'],
input[type='number'],
textarea {
  width: 100%;
  padding: 0.6rem;
  margin-bottom: 1rem;
  border-radius: 5px;
  border: none;
  background: #333;
  color: #eee;
  font-family: monospace;
  font-size: 1rem;
  resize: vertical;
}
button {
  background: #00ff99;
  border: none;
  color: #111;
  font-weight: 700;
  padding: 0.7rem 1.5rem;
  border-radius: 5px;
  cursor: pointer;
  font-size: 1.1rem;
  transition: background 0.3s ease;
}
button:hover {
  background: #00cc77;
}
.error {
  color: #ff6666;
  margin-bottom: 1rem;
  font-weight: 700;
}
.success {
  color: #00ff99;
  font-weight: 700;
  margin-bottom: 1rem;
}
.info {
  color: #bbb;
  font-size: 0.9rem;
  margin-bottom: 1rem;
}
footer {
  text-align: center;
  padding: 1rem;
  background: #1f1f1f;
  color: #666;
  font-size: 0.9rem;
}

/* Responsivita */
@media (max-width: 640px) {
  main {
    flex-direction: column;
    margin: 1rem;
  }
  section.box {
    flex: 1 1 100%;
    margin-bottom: 1rem;
  }
  button {
    width: 100%;
  }
}