:root {
    --bg: #1e1e2f;         /* màu nền chung (background) */
    --bg-sb: #2c3e50;
    --bg-sb-h: #34495e;
    --card: #2a2a3d;       /* màu thẻ card */
    --accent: #ffcc00;     /* màu nhấn (button, highlight) */
    --muted: #b0b3c1;      /* màu chữ phụ */
    --glass: rgba(255, 255, 255, 0.05);
    --cl: #e6eef6
}

* {
    box-sizing: border-box
}

body {
    margin: 0;
    font-family: Inter, system-ui, -apple-system, 'Segoe UI', Roboto, 'Helvetica Neue', Arial;
    background: var(--bg);
    color: var(--cl);
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
    min-height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
    padding: 32px;
}

/* Sidebar mặc định (PC) */
.sidebar {
    width: 220px;
    background: var(--bg-sb);
    color: #fff;
    height: 100vh;
    position: fixed;
    top: 0;
    left: 0;
    padding-top: 20px;
    transition: 0.3s;
}


.sidebar h2 {
    text-align: center;
    margin-bottom: 30px;
}


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


.sidebar ul li {
    padding: 15px 20px;
    border-left: 4px solid transparent;
    cursor: pointer;
    transition: 0.3s;
}


.sidebar ul li:hover {
    background: var(--bg-sb-h);
    border-left: 4px solid #1abc9c;
}


.sidebar ul li a {
    text-decoration: none;
    color: #fff;
    display: block;
}


/* Nội dung */
.main {
    margin-left: 220px;
    padding: 20px;
    transition: 0.3s;
    flex: 1;
    display: flex;
    flex-direction: column;
    height: 100vh;
}

.toggle-btn {
    display: none;
}

@media (max-width: 768px) {

    /* Sidebar mặc định ẩn */
    .sidebar {
        left: -220px;
    }

    /* Khi bật active thì trượt ra */
    .sidebar.active {
        left: 0;
    }

    /* Nút toggle hiện ra */
    .toggle-btn {
        display: block;
        position: fixed;
        left: 10px;
        top: 10px;
        /* background: #2c3e50;
    color: white; */
        border: none;
        padding: 10px 15px;
        cursor: pointer;
        font-size: 18px;
        z-index: 1000;
        border-radius: 5px;
    }

    /* Nội dung chiếm full khi sidebar ẩn */
    .content {
        margin-left: 0;
    }
}