body { font-family: 'Segoe UI', sans-serif; margin: 0; background: #f0f2f5; color: #333; }
.header { background: #fff; padding: 15px; box-shadow: 0 2px 10px rgba(0,0,0,0.1); position: sticky; top: 0; z-index: 100; }
.nav { display: flex; justify-content: center; gap: 15px; flex-wrap: wrap; }

.btn { 
  text-decoration: none; 
  padding: 10px 20px; 
  background: #007bff; 
  color: white; 
  border-radius: 5px;
  font-weight: 500;
}

.btn:hover { background: #0056b3; }

.container { max-width: 1100px; margin: 30px auto; padding: 0 20px; }
.card { 
  background: #fff; 
  border-radius: 12px; 
  box-shadow: 0 4px 15px rgba(0,0,0,0.08);
  padding: 30px;
}

.content { margin-bottom: 30px; min-height: 150px; }

.grid { display: flex; gap: 20px; flex-wrap: wrap; }
.box { 
  flex: 1; 
  min-width: 280px; 
  transition: 0.3s;
  border-bottom: 4px solid #007bff; 
}
.box:hover { box-shadow: 0 8px 25px rgba(0,0,0,0.15); }

.pincode-wrapper {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 20px;
    font-family: sans-serif;
    margin-top: 10px;
}

#pinInput {
    width: 200px;
    height: 50px;
    text-align: center;
    font-size: 24px;
    letter-spacing: 10px;
    border: 2px solid #ccc;
    border-radius: 8px;
}

.numpad {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 10px;
}

.numpad button {
    width: 60px;
    height: 60px;
    font-size: 20px;
    cursor: pointer;
    border: 1px solid #ddd;
    border-radius: 50%;
    background: #f9f9f9;
    transition: 0.2s;
}

.numpad button:active {
    background: #e0e0e0;
}

.submit-btn {
    width: 200px;
    padding: 12px;
    background: #007bff;
    color: white;
    border: none;
    border-radius: 5px;
    cursor: pointer;
    opacity: 0.5;
}

.submit-btn:not(:disabled) {
    opacity: 1;
}

.center {
    text-align: center;
}

@media (max-width: 600px) {
  .box { flex: 1 1 100%; }
}