/* Tabs container */
#tabs {
    background-color: #e5e5e5;
    padding: 4px 8px;
    border-bottom: 1px solid #b0b0b0;
    display: flex;
    gap: 4px;
    align-items: flex-end;
    height: 36px;
    overflow-x: auto;
    border-top: 1px solid #666;
    border-bottom: 1px solid #b0b0b0;
}

/* Tab appearance */
.tab {
    display: inline-flex;
    align-items: center;
    background: linear-gradient(to bottom, #f4f4f4, #e4e4e4);
    padding: 6px 10px;
    font-size: 13px;
    border: 1px solid #bbb;
    border-bottom: none;
    border-top-left-radius: 6px;
    border-top-right-radius: 6px;
    cursor: pointer;
    user-select: none;
    box-shadow: 0 1px 2px rgba(0, 0, 0, 0.15);
    max-width: 180px;
    overflow: hidden;
    white-space: nowrap;
    text-overflow: ellipsis;
    transition: margin 200ms ease, transform 200ms ease;
}

.tab:hover {
    background-color: #eaeaea;
}

.tab.active {
    background-color: #fff;
    font-weight: bold;
    z-index: 2;
    box-shadow: none;
}

/* Tab close button */
.tab button {
    margin-left: 8px;
    background-color: #ccc;
    border: none;
    border-radius: 4px;
    width: 16px;
    height: 16px;
    font-size: 12px;
    font-weight: bold;
    color: #333;
    cursor: pointer;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    padding: 0;
}

.tab button:hover {
    background-color: #d9534f;
    color: white;
}

/* Tab content area */
.tab-frame {
    width: 100%;
    height: 100%;
    border: none;
}

#iframe-loader {
    display: none;
}

/* Drag-and-drop visual feedback for tabs */
.tab.drag-over {
    transform: translateX(5px);
    background-color: #eef6ff;
    border-left: 2px solid #0078d4;
}