body {
    background-color: #f8fbf9;
}

/*サブタイトル*/
.sub-header {
    background-color: #f8fbf9;
    border-radius: 5px;
    padding: 1rem 1.5rem;
    margin-bottom: 2rem;
}

    .sub-header h2 {
        font-weight: 700;
        color: #198754;
        margin-bottom: 0;
    }

    .sub-header i {
        font-size: 1.5rem;
        color: #198754;
        margin-right: 0.5rem;
    }

    .sub-header small {
        color: #6c757d;
    }

/* 下線付きラベル */
.label-success-underline {
    display: inline-block;
    border-bottom: 1.5px solid #198754;
    padding-bottom: 0;
    margin-bottom: 0.25rem;
}

/* ログイン、登録、変更ボタンなど */
.btn-main {
    background-color: #198754;
    color: white;
    font-weight: 600;
    border: none;
    padding: 0.5rem;
    border-radius: 0.3rem;
}

    .btn-main:hover {
        background-color: #145c33;
        color: #fff;
    }

/*緑系ボタン*/
.btn-outline-success, .btn-outline-warning {
    font-weight: 500;
}

/* 戻るボタン右上 */
.btn-back {
    position: absolute;
    top: 1rem;
    right: 5%;
    font-size: 0.75rem;
    background-color: #e9ecef;
    border: 1px solid #ced4da;
}

    .btn-back:hover {
        background-color: #6c757d;
        color: #fff;
    }

/* 入力エラー */
.text-danger {
    font-size: 0.8rem;
    margin-top: 0.25rem;
}

/* エラー時の input の枠を赤く */
input.input-validation-error,
select.input-validation-error,
textarea.input-validation-error {
    border-color: #dc3545; /* Bootstrap の赤色 */
    box-shadow: 0 0 0 .2rem rgba(220,53,69,.25);
    transition: all .3s ease-in-out;
}