:root {
    --primary-color: #1f8f5f;
    --primary-hover: #18774f;
    --accent-color: #1f6feb;
    --accent-hover: #1a5dcc;
    --danger-color: #d93f3f;
    --danger-hover: #b53030;
    --border-color: #d9e1e7;
    --surface-color: #ffffff;
    --bg-color: #f2f5f8;
    --muted-text: #5c6570;
    --text-color: #202833;
    --shadow: 0 4px 18px rgba(0, 0, 0, 0.08);
}

* {
    box-sizing: border-box;
}

body {
    margin: 0;
    padding: 20px;
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    color: var(--text-color);
    background: var(--bg-color);
    line-height: 1.5;
}

.container {
    max-width: 1040px;
    margin: 0 auto;
    padding: 24px;
    border-radius: 12px;
    background: var(--surface-color);
    box-shadow: var(--shadow);
}

.top-bar {
    display: flex;
    justify-content: space-between;
    align-items: flex-end;
    gap: 16px;
    margin-bottom: 20px;
}

.heading-wrap h1 {
    margin: 0;
    font-size: 2rem;
    color: var(--primary-color);
}

.description {
    margin: 8px 0 0;
    color: var(--muted-text);
}

.btn {
    border: none;
    border-radius: 8px;
    cursor: pointer;
    font-size: 0.95rem;
    font-weight: 600;
    transition: background-color 0.2s ease, transform 0.2s ease;
    padding: 10px 16px;
}

.btn:hover {
    transform: translateY(-1px);
}

.add-group-btn {
    background: var(--primary-color);
    color: #fff;
    white-space: nowrap;
}

.add-group-btn:hover {
    background: var(--primary-hover);
}

.empty-state {
    margin: 0;
    border: 2px dashed var(--border-color);
    border-radius: 10px;
    padding: 18px;
    text-align: center;
    color: var(--muted-text);
    background: #fbfcfd;
}

.groups-list {
    display: flex;
    flex-direction: column;
    gap: 18px;
}

.group-card {
    border: 1px solid var(--border-color);
    border-radius: 12px;
    padding: 16px;
    background: #fcfdff;
    box-shadow: 0 2px 8px rgba(0, 0, 0, 0.05);
}

.group-header {
    display: flex;
    gap: 10px;
    align-items: center;
}

.group-name-input,
.item-name-input,
.item-add-name,
.item-content,
.item-add-content {
    width: 100%;
    border: 1px solid var(--border-color);
    border-radius: 8px;
    padding: 10px 12px;
    font-size: 0.95rem;
    color: var(--text-color);
    background: #fff;
}

.group-name-input,
.item-name-input,
.item-add-name {
    height: 42px;
}

.item-content,
.item-add-content {
    min-height: 92px;
    resize: vertical;
}

.item-content {
    margin-top: 10px;
    background: #f7f9fc;
}

.item-content.editing {
    background: #fffdf2;
    border-color: #e1b858;
}

.item-content:focus,
.group-name-input:focus,
.item-name-input:focus,
.item-add-name:focus,
.item-add-content:focus {
    outline: none;
    border-color: #4f8de6;
    box-shadow: 0 0 0 3px rgba(79, 141, 230, 0.18);
}

.group-items {
    display: grid;
    gap: 12px;
    margin-top: 14px;
}

.item-card {
    border: 1px solid #e3e8ef;
    border-radius: 10px;
    background: #fff;
    padding: 12px;
}

.item-actions {
    display: flex;
    gap: 8px;
    margin-top: 10px;
    flex-wrap: wrap;
}

.edit-btn {
    background: #2f6fd7;
    color: #fff;
}

.edit-btn:hover {
    background: #245ab2;
}

.save-btn {
    background: #298a53;
    color: #fff;
}

.save-btn:hover {
    background: #1f6d41;
}

.cancel-btn {
    background: #e6ebf2;
    color: #27303a;
}

.cancel-btn:hover {
    background: #d9e1ec;
}

.danger-btn {
    background: var(--danger-color);
    color: #fff;
}

.danger-btn:hover {
    background: var(--danger-hover);
}

.copy-item-btn {
    width: 100%;
    margin-top: 10px;
    background: var(--accent-color);
    color: #fff;
    font-size: 1rem;
    font-weight: 700;
    padding: 14px 16px;
}

.copy-item-btn:hover {
    background: var(--accent-hover);
}

.item-add-form {
    margin-top: 14px;
    padding-top: 14px;
    border-top: 1px dashed var(--border-color);
    display: grid;
    gap: 10px;
}

.add-item-btn {
    justify-self: flex-start;
    background: var(--primary-color);
    color: #fff;
}

.add-item-btn:hover {
    background: var(--primary-hover);
}

.toast {
    position: fixed;
    right: 20px;
    bottom: 20px;
    background: #1f8f5f;
    color: #fff;
    border-radius: 8px;
    padding: 12px 16px;
    box-shadow: var(--shadow);
    opacity: 0;
    transform: translateY(20px);
    pointer-events: none;
    transition: opacity 0.25s ease, transform 0.25s ease;
    max-width: 420px;
    z-index: 999;
}

.toast.show {
    opacity: 1;
    transform: translateY(0);
}

.toast.error {
    background: #d93f3f;
}

@media (max-width: 900px) {
    .container {
        padding: 18px;
    }

    .top-bar {
        align-items: stretch;
        flex-direction: column;
    }

    .add-group-btn {
        align-self: flex-end;
    }
}

@media (max-width: 600px) {
    body {
        padding: 12px;
    }

    .container {
        padding: 14px;
    }

    .heading-wrap h1 {
        font-size: 1.6rem;
    }

    .item-actions .btn,
    .add-item-btn,
    .add-group-btn,
    .danger-btn {
        width: 100%;
    }

    .add-group-btn {
        align-self: stretch;
    }

    .toast {
        left: 12px;
        right: 12px;
        bottom: 12px;
        max-width: none;
    }
}

/* ホームボタンのスタイル */
.home-header {
    background-color: #4CAF50;
    text-align: center;
    padding: 15px 0;
    box-shadow: 0 2px 4px rgba(0,0,0,0.2);
    position: relative;
    z-index: 1000;
    margin-bottom: 20px;
}

.home-button {
    display: inline-block;
    color: white;
    padding: 8px 15px;
    text-decoration: none;
    font-weight: bold;
    transition: all 0.3s ease;
}

/* PC表示時のスタイル */@media (min-width: 768px) {    .home-header {        text-align: right;        padding: 10px 20px;        background-color: transparent;        box-shadow: none;    }        .home-button {        display: inline-block;        background-color: #4CAF50;        border-radius: 5px;        box-shadow: 0 2px 4px rgba(0,0,0,0.2);        margin-right: 10px;    }        .home-button:hover {        background-color: #45a049;        box-shadow: 0 4px 8px rgba(0,0,0,0.3);        transform: translateY(-2px);    }}