:root {
    --brand: #1e6f9f;
    --brand-light: #e7f2f8;
    --brand-soft: rgba(30, 111, 159, 0.07);
    --body-bg: #f5f7f9;
    --card-bg: #fff;
    --text: #1c2533;
    --text-secondary: #697484;
    --border: #e4e7ec;
    --topbar-h: 56px;
    --sidebar-w: 240px;
    --radius: 8px;
    --radius-sm: 6px;
    --shadow-sm: 0 1px 2px rgba(0, 0, 0, 0.03);
    --shadow-md: 0 4px 14px rgba(0, 0, 0, 0.05);
    --transition: 0.22s cubic-bezier(0.4, 0, 0.2, 1);
    --success: #2e8b57;
    --danger: #c94a3b;
}

* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

html, body {
    height: 100%;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
    background: var(--body-bg);
    color: var(--text);
    line-height: 1.5;
    overflow: hidden;
}

/* ---- 顶栏 ---- */
.topbar {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    height: var(--topbar-h);
    background: var(--card-bg);
    border-bottom: 1px solid var(--border);
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 0 22px 0 18px;
    z-index: 200;
    box-shadow: 0 1px 3px rgba(0, 0, 0, 0.02);
}

.topbar-left {
    display: flex;
    align-items: center;
    gap: 10px;
}

.brand-icon {
    width: 34px;
    height: 34px;
    border-radius: var(--radius);
    background: var(--brand);
    display: flex;
    align-items: center;
    justify-content: center;
    color: #fff;
    font-size: 16px;
    font-weight: 700;
    flex-shrink: 0;
}

.brand-text {
    font-size: 15px;
    font-weight: 600;
    color: var(--text);
    letter-spacing: -0.3px;
}

.brand-sub {
    font-size: 10px;
    color: var(--text-secondary);
    letter-spacing: 1px;
    text-transform: uppercase;
}

.topbar-right {
    display: flex;
    align-items: center;
    gap: 16px;
    position: relative;
}

.user-btn {
    display: flex;
    align-items: center;
    gap: 8px;
    cursor: pointer;
    padding: 4px 10px 4px 4px;
    border-radius: 40px;
    transition: var(--transition);
}

.user-btn:hover {
    background: var(--body-bg);
}

.user-avatar {
    width: 32px;
    height: 32px;
    border-radius: 50%;
    background: var(--brand);
    color: #fff;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 13px;
    font-weight: 600;
    flex-shrink: 0;
}

.user-info {
    line-height: 1.3;
}

.user-name {
    font-size: 13px;
    color: var(--text);
    font-weight: 500;
}

.user-role {
    font-size: 11px;
    color: var(--text-secondary);
}

.user-dropdown {
    position: absolute;
    top: calc(var(--topbar-h) - 10px);
    right: 18px;
    background: var(--card-bg);
    border-radius: var(--radius-sm);
    box-shadow: 0 6px 20px rgba(0, 0, 0, 0.12);
    z-index: 300;
    min-width: 150px;
    padding: 4px;
    display: none;
    border: 1px solid var(--border);
}

.user-dropdown.show {
    display: block;
}

.dd-item {
    display: flex;
    align-items: center;
    gap: 8px;
    height: 36px;
    padding: 0 12px;
    border-radius: var(--radius-sm);
    cursor: pointer;
    font-size: 13px;
    color: var(--text);
    transition: background var(--transition);
}

.dd-item:hover {
    background: var(--body-bg);
}

.dd-item.logout {
    color: var(--danger);
}

/* ---- 侧边栏 ---- */
.sidebar {
    position: fixed;
    top: var(--topbar-h);
    left: 0;
    bottom: 0;
    width: var(--sidebar-w);
    background: var(--card-bg);
    overflow-y: auto;
    z-index: 199;
    padding: 16px 12px;
    display: flex;
    flex-direction: column;
    border-right: 1px solid var(--border);
}

.sidebar::-webkit-scrollbar {
    width: 3px;
}

.sidebar::-webkit-scrollbar-thumb {
    background: #d0d5dd;
    border-radius: 2px;
}

.menu-group {
    margin-bottom: 2px;
}

.menu-group .group-title {
    display: flex;
    align-items: center;
    gap: 10px;
    height: 40px;
    padding: 0 12px;
    cursor: pointer;
    color: var(--text-secondary);
    font-size: 12.5px;
    font-weight: 600;
    transition: var(--transition);
    user-select: none;
    border-radius: var(--radius-sm);
    letter-spacing: 0.2px;
}

.menu-group .group-title:hover {
    color: var(--text);
    background: #f4f7fa;
}

.menu-group .group-title .icon-wrap {
    width: 30px;
    height: 30px;
    border-radius: var(--radius-sm);
    display: flex;
    align-items: center;
    justify-content: center;
    flex-shrink: 0;
    transition: var(--transition);
    color: var(--text-secondary);
}

.menu-group .group-title svg {
    width: 16px;
    height: 16px;
}

.menu-group.open .group-title .icon-wrap {
    color: var(--brand);
}

.menu-group .group-title .arrow {
    margin-left: auto;
    font-size: 10px;
    transition: transform var(--transition);
    opacity: 0.35;
}

.menu-group.open .group-title .arrow {
    transform: rotate(90deg);
    opacity: 0.6;
}

.menu-group.open .group-title {
    color: var(--text);
    font-weight: 600;
}

.submenu {
    overflow: hidden;
    max-height: 0;
    transition: max-height 0.3s ease;
}

.menu-group.open .submenu {
    max-height: 500px;
}

.submenu .menu-item {
    display: flex;
    align-items: center;
    gap: 8px;
    height: 34px;
    padding: 0 12px 0 52px;
    cursor: pointer;
    color: var(--text-secondary);
    font-size: 12.5px;
    transition: var(--transition);
    border-radius: var(--radius-sm);
    position: relative;
    margin: 1px 0;
}

.submenu .menu-item::before {
    content: '';
    position: absolute;
    left: 38px;
    width: 4px;
    height: 4px;
    border-radius: 2px;
    background: #cdd3db;
    transition: var(--transition);
}

.submenu .menu-item:hover {
    color: var(--text);
    background: #f4f7fa;
}

.submenu .menu-item.active {
    color: var(--brand);
    background: var(--brand-light);
    font-weight: 500;
}

.submenu .menu-item.active::before {
    background: var(--brand);
    box-shadow: 0 0 0 2px rgba(30, 111, 159, 0.15);
}

.sidebar-footer {
    margin-top: auto;
    padding: 8px 14px;
    display: flex;
    align-items: center;
    gap: 8px;
    font-size: 11px;
    color: #b0b8c2;
}

.sidebar-footer .dot {
    width: 5px;
    height: 5px;
    border-radius: 50%;
    background: var(--success);
}

/* ---- 主内容区 ---- */
.main {
    position: fixed;
    top: var(--topbar-h);
    left: var(--sidebar-w);
    right: 0;
    bottom: 0;
    background: var(--body-bg);
}

#contentFrame {
    width: 100%;
    height: 100%;
    border: none;
    background: var(--body-bg);
    display: block;
}