body {
  font-family: sans-serif;
  margin: 0;
  padding: 0;
  background: #f5f5f5;
  color: #222;
}

header, footer {
  background: #cceeff;
  padding: 1rem;
  text-align: center;
}

nav ul {
  list-style: none;
  padding: 0;
  display: flex;
  justify-content: center;
  gap: 1rem;
}

header a {
  text-decoration: none;
  color: #003366;
  font-weight: bold;
}

header a:hover {
  color: #000;
}

section {
  text-align: center;
  padding: 2rem 1rem;
}

section p {
  max-width: 600px;
  margin: 0 auto;
}

.popup, .confirm-popup {
  display: none;
  position: fixed;
  top: 0; left: 0;
  width: 100%; height: 100%;
  background: rgba(0,0,0,0.5);
  z-index: 1000;
  justify-content: center;
  align-items: center;
}

.popup-content, .confirm-content {
  background: white;
  padding: 20px;
  border-radius: 5px;
  width: 90%;
  max-width: 400px;
  position: relative;
  text-align: center;
  color: #222;
}

.popup-content input, .popup-content textarea {
  width: 100%;
  margin-bottom: 10px;
  padding: 8px;
}

.popup-content button, .confirm-content button {
  padding: 10px 20px;
  background-color: #0077cc;
  color: white;
  border: none;
  cursor: pointer;
}

.popup-content button:hover, .confirm-content button:hover {
  background-color: #005fa3;
}

.close {
  position: absolute;
  top: 10px;
  right: 15px;
  cursor: pointer;
  font-weight: bold;
  font-size: 1.2rem;
  color: #333;
}

.error {
  color: red;
  font-size: 0.9em;
  margin-top: -5px;
  margin-bottom: 10px;
  display: none;
}