body, html {
    height: 100%;
    margin: 0;
    font-family: 'Segoe UI', 'Helvetica Neue', Arial, sans-serif;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    display: flex;
    justify-content: center;
    align-items: center;
    color: #333;
}

.login-selection-container, .login-form-container {
    background-color: #ffffff;
    padding: 40px 50px;
    border-radius: 12px;
    box-shadow: 0 10px 25px rgba(0, 0, 0, 0.15);
    text-align: center;
    width: 100%;
    max-width: 380px;
    animation: fadeIn 0.5s ease-out;
}

@keyframes fadeIn {
    from { opacity: 0; transform: translateY(-20px); }
    to { opacity: 1; transform: translateY(0); }
}

h1 {
    color: #333;
    margin-bottom: 35px;
    font-size: 28px;
    font-weight: 600;
}

.login-button, .login-submit-button {
    display: block;
    width: 100%;
    padding: 14px;
    margin-bottom: 18px;
    border: none;
    border-radius: 8px;
    font-size: 16px;
    font-weight: bold;
    color: #fff;
    cursor: pointer;
    transition: all 0.3s ease;
    box-shadow: 0 2px 5px rgba(0,0,0,0.1);
}

.login-button:hover, .login-submit-button:hover {
    transform: translateY(-2px);
    box-shadow: 0 4px 10px rgba(0,0,0,0.15);
}

.cast-login { background: linear-gradient(45deg, #ff80ab, #ff69b4); } /* ピンク系 */
.staff-login { background: linear-gradient(45deg, #56ccf2, #2f80ed); } /* 青系 */
.admin-submit { background: linear-gradient(45deg, #6ab04c, #4CAF50); } /* 緑系 - ログインフォーム用 */

.admin-login-link {
    display: block;
    text-align: right;
    margin-top: 30px;
    font-size: 13px;
}

.admin-login-link a {
    color: #888;
    text-decoration: none;
    transition: color 0.2s ease;
}

.admin-login-link a:hover {
    color: #555;
    text-decoration: underline;
}

.form-group {
    margin-bottom: 20px;
    text-align: left;
}

.form-group label {
    display: block;
    margin-bottom: 8px;
    color: #555;
    font-weight: 600;
    font-size: 14px;
}

.form-group input[type="text"],
.form-group input[type="password"] {
    width: 100%;
    padding: 12px 15px;
    border: 1px solid #ddd;
    border-radius: 8px;
    box-sizing: border-box;
    font-size: 15px;
    transition: border-color 0.2s ease;
}

.form-group input[type="text"]:focus,
.form-group input[type="password"]:focus {
    border-color: #4267B2; /* メインカラー */
    outline: none;
    box-shadow: 0 0 0 2px rgba(66, 103, 178, 0.2);
}

.error-msg {
    color: #d9534f; /* 赤系 */
    background-color: #f2dede;
    border: 1px solid #ebccd1;
    padding: 10px;
    border-radius: 5px;
    margin-bottom: 20px;
    font-size: 14px;
}
.back-link {
    display: block;
    text-align: center;
    margin-top: 25px;
    font-size: 14px;
}
.back-link a {
    color: #555;
    text-decoration: none;
    transition: color 0.2s ease;
}
.back-link a:hover {
    color: #333;
    text-decoration: underline;
}