html,
body {
    height: 100%;
    margin: 0;
    padding: 0;
}

body {
    background-image: url('../images/blood_donation_bg2.jpg');
    background-size: cover;
    background-position: center;
    background-attachment: fixed;
    display: flex;
    flex-direction: column;
}

body>.container {
    flex: 1;
}

header {
    background: rgba(220, 20, 60, 0.8);
    color: white;
    padding: 20px 0;
    text-align: center;
}

.register-form {
    background: rgba(255, 255, 255, 0.9);
    padding: 30px;
    border-radius: 15px;
    box-shadow: 0 0 20px rgba(0, 0, 0, 0.3);
    position: relative;
    overflow: hidden;
}

.register-overlay {
    position: absolute;
    inset: 0;
    background: rgba(0, 0, 0, 0.45);
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    gap: 1rem;
    z-index: 10;
    cursor: pointer;
    text-align: center;
}

.register-overlay img {
    width: auto;
    height: auto;
    max-width: 100%;
    max-height: 90%;
    border-radius: 15px;
    box-shadow: 0 0 20px rgba(0, 0, 0, 0.4);
    object-fit: contain;
}

.register-overlay .overlay-text {
    color: #fff;
    font-size: 1rem;
    font-weight: 600;
    text-shadow: 0 0 12px rgba(0, 0, 0, 0.7);
}

.search-form {
    background: rgba(255, 255, 255, 0.9);
    padding: 30px;
    border-radius: 15px;
    box-shadow: 0 0 20px rgba(0, 0, 0, 0.3);
    margin-bottom: 20px;
}

.donor-table {
    background: rgba(255, 255, 255, 0.9);
    padding: 30px;
    border-radius: 15px;
    box-shadow: 0 0 20px rgba(0, 0, 0, 0.3);
}

footer {
    background: rgba(0, 0, 0, 0.8);
    color: white;
    text-align: center;
    padding: 20px 0;
}