body {
    margin: 0;
    font-family: "Microsoft YaHei", sans-serif;
    background-color: #0d0d2b;
    color: #ffffff;
}

header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 15px 30px;
    background-color: #0b0b25;
}

header .logo img {
    height: 40px;
}

header nav a {
    color: #ffffff;
    margin-left: 20px;
    text-decoration: none;
    font-weight: bold;
}

header .logout button {
    background-color: #3a22d0;
    color: #fff;
    border: none;
    padding: 6px 15px;
    border-radius: 5px;
    cursor: pointer;
}

.sidebar {
    position: fixed;
    top: 60px;
    left: 0;
    width: 200px;
    background-color: #12123b;
    height: calc(100vh - 60px);
    padding: 20px;
}

.sidebar ul {
    list-style: none;
    padding: 0;
}

.sidebar ul li {
    margin-bottom: 15px;
    cursor: pointer;
}

.main-content {
    margin-left: 220px;
    padding: 30px;
}

.dashboard {
    display: flex;
    gap: 20px;
}

.dashboard .card {
    background-color: #12123b;
    border-radius: 12px;
    padding: 20px;
    text-align: center;
    flex: 1;
}

table {
    width: 100%;
    border-collapse: collapse;
    margin-top: 20px;
    background-color: #12123b;
    border-radius: 12px;
}

table th, table td {
    padding: 10px;
    text-align: center;
    border-bottom: 1px solid #1b1b42;
}