* {
    box-sizing: border-box;
}

body {
    margin: 0;
    font-family: Arial, Helvetica, sans-serif;
    background: #f5f6f8;
    color: #222;
}

a {
    text-decoration: none;
    color: inherit;
}

.app-wrapper {
    min-height: 100vh;
}

.topbar {
    height: 60px;
    background: #1f2937;
    color: #fff;
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 0 24px;
}

.brand a {
    font-size: 20px;
    font-weight: bold;
}

.user-area {
    display: flex;
    align-items: center;
    gap: 20px;
}

.user-area a {
    color: #fff;
}

.sidebar {
    position: fixed;
    top: 60px;
    left: 0;
    bottom: 0;
    width: 230px;
    background: #111827;
    padding: 20px 0;
}

.sidebar-nav {
    display: flex;
    flex-direction: column;
}

.sidebar-nav a {
    color: #d1d5db;
    padding: 13px 22px;
}

.sidebar-nav a:hover {
    background: #1f2937;
    color: #fff;
}

.main-content {
    margin-left: 230px;
    padding: 25px;
    min-height: calc(100vh - 60px);
}

.page-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 25px;
}

.page-header h1 {
    margin: 0;
}

.card {
    background: #fff;
    border-radius: 8px;
    padding: 20px;
    box-shadow: 0 1px 4px rgba(0, 0, 0, 0.08);
}

.btn {
    display: inline-block;
    padding: 9px 15px;
    border-radius: 5px;
    border: none;
    cursor: pointer;
    background: #2563eb;
    color: #fff;
}

.btn:hover {
    opacity: 0.9;
}

.btn-danger {
    background: #dc2626;
}

.btn-secondary {
    background: #6b7280;
}

.form-group {
    margin-bottom: 16px;
}

.form-group label {
    display: block;
    margin-bottom: 6px;
    font-weight: 600;
}

.form-control {
    width: 100%;
    padding: 10px;
    border: 1px solid #d1d5db;
    border-radius: 5px;
}

table {
    width: 100%;
    border-collapse: collapse;
    background: #fff;
}

th,
td {
    padding: 11px;
    border-bottom: 1px solid #e5e7eb;
    text-align: left;
}

th {
    background: #f3f4f6;
}

@media (max-width: 768px) {

    .sidebar {
        width: 190px;
    }

    .main-content {
        margin-left: 190px;
    }

    .topbar {
        padding: 0 15px;
    }
}

@media (max-width: 600px) {

    .sidebar {
        position: static;
        width: 100%;
    }

    .main-content {
        margin-left: 0;
    }

    .topbar {
        height: auto;
        padding: 15px;
        flex-direction: column;
        gap: 10px;
    }

    .user-area {
        flex-direction: column;
        gap: 5px;
    }
}