* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

body {
  font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
  background: linear-gradient(135deg, #ffffff 0%, #dffeea 100%);
  min-height: 100vh;
  color: #333;
  display: flex;
  flex-direction: column;
}

.nav-buttons {
  display: flex;
  justify-content: flex-end;
  gap: 0.5rem;
  padding: 1rem 2rem 0;
  flex-wrap: wrap;
}

.nav-btn {
  background: #f7f9ff;
  color: #1f2937;
  border: 1px solid #d5ddf6;
  padding: 0.6rem 1.1rem;
  border-radius: 12px;
  text-decoration: none;
  font-weight: 600;
  cursor: pointer;
  display: inline-flex;
  align-items: center;
  gap: 0.45rem;
  transition: transform 0.2s ease, box-shadow 0.2s ease, border-color 0.2s ease;
  box-shadow: 0 6px 18px rgba(102, 126, 234, 0.12);
}

.nav-btn.nav-btn-secondary {
  background: #f4f5f7;
  border-color: #cbd5e1;
  color: #1f2937;
}

.nav-btn:hover {
  transform: translateY(-2px);
  box-shadow: 0 8px 20px rgba(102, 126, 234, 0.2);
  border-color: #a3b0f8;
}

main {
  flex-grow: 1;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 2rem;
}

.card {
  background: rgba(255, 255, 255, 0.95);
  backdrop-filter: blur(10px);
  border-radius: 20px;
  padding: 2.5rem;
  box-shadow: 0 10px 30px rgba(0, 0, 0, 0.1);
  max-width: 400px;
  width: 100%;
  text-align: left;
}

.card h2 {
  color: #4a5568;
  font-size: 1.6rem;
  margin-bottom: 1.5rem;
  text-align: center;
}

label {
  font-weight: 600;
  display: block;
  margin-bottom: 0.3rem;
}

input {
  width: 100%;
  padding: 0.5rem;
  margin-bottom: 1rem;
  border: 1px solid #ccc;
  border-radius: 8px;
  font-size: 1rem;
}

.error {
  color: #c00;
  margin-bottom: 1rem;
}

.error ul {
  padding-left: 1.2rem;
}

.btn {
  background: linear-gradient(45deg, #7484de, #6c4397);
  color: white;
  padding: 0.75rem 1.5rem;
  border: none;
  border-radius: 25px;
  cursor: pointer;
  font-weight: 500;
  text-decoration: none;
  display: inline-block;
  width: 100%;
  text-align: center;
  transition: transform 0.2s ease, box-shadow 0.2s ease;
}

.btn:hover {
  transform: translateY(-2px);
  box-shadow: 0 5px 15px rgba(102, 126, 234, 0.4);
}