body {
    margin: 0;
    font-family: "Segoe UI", sans-serif;
    background: #f2f2f2;
}

/* ツールバー */
.toolbar {
    display: flex;
    align-items: center;
    background: #e1e1e1;
    padding: 4px 8px;
    border-bottom: 1px solid #ccc;
}

.toolbar button {
    margin-right: 6px;
    padding: 6px 10px;
    border: none;
    background: transparent;
    font-size: 16px;
    cursor: pointer;
    border-radius: 4px;
}

.toolbar button:hover {
    background: #d6d6d6;
}

.status {
    margin-left: auto;
    font-size: 12px;
    color: #666;
}

/* タブバー */
.tab-bar {
    display: flex;
    align-items: flex-end;
    background: #ddd;
    padding: 0 6px;
    overflow-x: scroll;
    white-space: nowrap;
}

.tab {
    display: flex;
    align-items: center;
    background: #cfcfcf;
    margin-right: 4px;
    border-top-left-radius: 6px;
    border-top-right-radius: 6px;
    padding: 6px 10px;
    cursor: pointer;
    position: relative;
    top: 2px;
}

.tab.active {
    background: #fff;
    border: 1px solid #ccc;
    border-bottom: none;
    top: 0;
}

.tab span {
    margin-right: 8px;
}

.tab .close {
    font-size: 14px;
    color: #666;
    cursor: pointer;
}

.tab .close:hover {
    color: #c00;
}

/* ＋ボタン */
.add-tab {
    background: transparent;
    border: none;
    font-size: 18px;
    cursor: pointer;
    padding: 6px 10px;
    margin-left: auto;
    color: #555;
}

.add-tab:hover {
    background: #d6d6d6;
    border-radius: 4px;
}

/* iframe */
.tab-content iframe {
    width: 100%;
    height: calc(100vh - 90px);
    border: none;
    display: none;
    background: #fff;
}

.tab-content iframe.active {
    display: block;
}

/* ステータスバー */
.statusbar {
    height: 20px;
    background: #f9f9f9;
    border-top: 1px solid #ccc;
    font-size: 12px;
    color: #555;
    padding: 2px 8px;
}

.tab.dragging {
    opacity: 0.5; /* ドラッグ中のタブを半透明にする */
    border: 2px dashed #007bff; /* 境界線を点線にする */
}