body.auth-page {
    min-height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
    background: linear-gradient(135deg, #0f0c29, #302b63, #24243e);
    font-family: 'Segoe UI', sans-serif;
}
.login-card, .invite-card {
    width: 100%;
    max-width: 400px;
    padding: 2.5rem 2rem;
    border-radius: 1rem;
    background: rgba(255, 255, 255, 0.06);
    backdrop-filter: blur(12px);
    border: 1px solid rgba(255, 255, 255, 0.1);
    box-shadow: 0 8px 32px rgba(0, 0, 0, 0.4);
}
.login-title {
    font-size: 1.8rem;
    font-weight: 700;
    letter-spacing: -0.5px;
}
.login-subtitle {
    color: rgba(255, 255, 255, 0.5);
    font-size: 0.9rem;
}
.kakao-btn {
    background-color: #FEE500;
    color: #191919;
    font-weight: 600;
    border: none;
    border-radius: 0.5rem;
    padding: 0.75rem 1rem;
    font-size: 1rem;
    transition: transform 0.1s, box-shadow 0.2s;
}
.kakao-btn:hover {
    background-color: #FDD800;
    color: #191919;
    transform: translateY(-1px);
    box-shadow: 0 4px 16px rgba(254, 229, 0, 0.3);
}
.admin-toggle {
    color: rgba(255, 255, 255, 0.25);
    font-size: 0.75rem;
    cursor: pointer;
    transition: color 0.2s;
    text-decoration: none;
}
.admin-toggle:hover {
    color: rgba(255, 255, 255, 0.5);
}
.admin-form .form-control {
    background: rgba(255, 255, 255, 0.08);
    border: 1px solid rgba(255, 255, 255, 0.12);
    color: #fff;
}
.admin-form .form-control:focus {
    background: rgba(255, 255, 255, 0.12);
    border-color: rgba(255, 255, 255, 0.3);
    color: #fff;
    box-shadow: none;
}
.admin-form .form-control::placeholder {
    color: rgba(255, 255, 255, 0.35);
}
.admin-form .form-check-label {
    color: rgba(255, 255, 255, 0.5);
    font-size: 0.85rem;
}
.admin-form .btn-login {
    background: rgba(255, 255, 255, 0.12);
    border: 1px solid rgba(255, 255, 255, 0.15);
    color: #fff;
}
.admin-form .btn-login:hover {
    background: rgba(255, 255, 255, 0.2);
}
.copyright {
    color: rgba(255, 255, 255, 0.2);
    font-size: 0.75rem;
}