/* Animated Professional Gradient */
body {
    font-family: 'Segoe UI', Helvetica, sans-serif;
    margin: 0;
    min-height: 100vh;
    background: linear-gradient(-45deg, #0f2027, #203a43, #2c5364, #141e30);
    background-size: 400% 400%;
    animation: gradientBG 15s ease infinite;
    color: #fff;
    display: flex;
    flex-direction: column;
    align-items: center;
}

@keyframes gradientBG {
    0% { background-position: 0% 50%; }
    50% { background-position: 100% 50%; }
    100% { background-position: 0% 50%; }
}

header {
    margin-top: 50px;
    text-align: center;
}

.container {
    width: 95%;
    max-width: 1100px;
    display: flex;
    gap: 30px;
    flex-wrap: wrap;
    justify-content: center;
    padding: 20px 0;
}

/* Formal 3D Glassmorphism */
.glass-3d {
    background: rgba(255, 255, 255, 0.05);
    backdrop-filter: blur(12px);
    border: 1px solid rgba(255, 255, 255, 0.1);
    border-radius: 12px;
    padding: 30px;
    box-shadow: 0 15px 35px rgba(0,0,0,0.5);
}

.registration-form { flex: 1; min-width: 350px; max-width: 450px; }
.attendee-list { flex: 2; min-width: 500px; }

/* Form Elements */
form { display: flex; flex-direction: column; }
label { font-size: 0.9rem; margin: 15px 0 5px 0; color: #ccc; }

input, select {
    padding: 12px;
    border-radius: 6px;
    border: 1px solid rgba(255,255,255,0.2);
    background: rgba(0,0,0,0.3);
    color: #fff;
    font-size: 1rem;
}

select option { background: #141e30; }

button {
    margin-top: 25px;
    padding: 14px;
    border: none;
    border-radius: 6px;
    background: #00d2ff;
    background: linear-gradient(to right, #3a7bd5, #00d2ff);
    color: white;
    font-weight: bold;
    cursor: pointer;
    text-transform: uppercase;
    letter-spacing: 1px;
}

button:disabled { opacity: 0.4; cursor: not-allowed; }

/* Table Section */
.filter-group { margin-bottom: 20px; }
.table-container { width: 100%; overflow-x: auto; }

table {
    width: 100%;
    border-collapse: collapse;
    margin-top: 10px;
}

th {
    background: rgba(255,255,255,0.1);
    padding: 15px;
    text-align: left;
    font-size: 0.85rem;
    text-transform: uppercase;
    color: #00d2ff;
}

td {
    padding: 15px;
    border-bottom: 1px solid rgba(255,255,255,0.05);
    font-size: 0.9rem;
}

.btn-edit { background: #f39c12; color: white; padding: 5px 10px; margin-right: 5px; font-size: 11px; }
.btn-del { background: #e74c3c; color: white; padding: 5px 10px; font-size: 11px; }

/* Note: Any styles relating to .back-btn have been removed from this file. */