.simple-reg-card {
    background: rgba(255, 255, 255, 0.95);
    border: 1px solid rgba(255, 255, 255, 0.5);
    border-radius: 20px;
    box-shadow: 0 15px 35px rgba(0, 0, 0, 0.1);
    backdrop-filter: blur(10px);
    max-width: 500px;
    margin: 0 auto;
}

/* Modal Styling */
.success-modal .modal-content {
    border-radius: 20px;
    border: none;
    box-shadow: 0 10px 30px rgba(0, 0, 0, 0.2);
}

.success-modal .modal-header {
    border-bottom: none;
    background: linear-gradient(135deg, #1a2a6c, #b21f1f);
    color: white;
    border-radius: 20px 20px 0 0;
    padding: 1.5rem;
}

.success-modal .modal-body {
    padding: 2rem;
    text-align: center;
}

.password-display {
    background: #f8f9fa;
    border: 2px dashed #dee2e6;
    padding: 1rem;
    border-radius: 10px;
    font-family: monospace;
    font-size: 1.5rem;
    font-weight: bold;
    color: #1a2a6c;
    margin: 1rem 0;
    cursor: pointer;
}

.password-note {
    font-size: 0.9rem;
    color: #6c757d;
    margin-bottom: 1.5rem;
}

.form-control-lg {
    border-radius: 12px;
    font-size: 1.1rem;
}

.hero-bg-simple {
    background: url('../media/images/soul_banner_bg.png') no-repeat center center fixed;
    background-size: cover;
    min-height: 100vh;
    padding-top: 80px;
    padding-bottom: 40px;
}

/* エラーメッセージのプロフェッショナルなスタイル設計 */
.custom-alert-error {
    background-color: #ffffff;
    border-left: 4px solid #dc3545;
    color: #495057;
    padding: 1rem 1.25rem;
    border-radius: 8px;
    box-shadow: 0 4px 12px rgba(220, 53, 69, 0.15);
    display: flex;
    align-items: flex-start;
    gap: 0.75rem;
    font-size: 0.95rem;
    transition: all 0.3s ease;
    animation: shake 0.5s cubic-bezier(.36, .07, .19, .97) both;
}

.custom-alert-error .error-icon {
    color: #dc3545;
    font-size: 1.2rem;
    margin-top: -2px;
}

@keyframes shake {

    10%,
    90% {
        transform: translate3d(-1px, 0, 0);
    }

    20%,
    80% {
        transform: translate3d(2px, 0, 0);
    }

    30%,
    50%,
    70% {
        transform: translate3d(-4px, 0, 0);
    }

    40%,
    60% {
        transform: translate3d(4px, 0, 0);
    }
}