* {
    box-sizing: border-box;
}

body {
    margin: 0;
    font-family: Arial, Helvetica, sans-serif;
    background: #f4f6f8;
    color: #222;
}

.topbar {
    background: #0f766e;
    color: white;
    padding: 15px 25px;
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.topbar-title {
    font-size: 22px;
    font-weight: bold;
}

.menu a {
    color: white;
    text-decoration: none;
    margin-left: 15px;
    font-weight: bold;
}

.menu a:hover {
    text-decoration: underline;
}

.container {
    width: 95%;
    max-width: 1300px;
    margin: 25px auto;
}

.card {
    background: white;
    border-radius: 8px;
    padding: 20px;
    margin-bottom: 20px;
    box-shadow: 0 2px 8px rgba(0,0,0,0.08);
}

.grid {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 15px;
}

.stat {
    background: white;
    border-left: 5px solid #0f766e;
    border-radius: 8px;
    padding: 18px;
    box-shadow: 0 2px 8px rgba(0,0,0,0.07);
}

.stat h3 {
    margin: 0;
    color: #555;
    font-size: 14px;
}

.stat p {
    font-size: 28px;
    margin: 8px 0 0;
    font-weight: bold;
}

.table {
    width: 100%;
    border-collapse: collapse;
    background: white;
}

.table th,
.table td {
    padding: 12px;
    border-bottom: 1px solid #ddd;
    text-align: left;
}

.table th {
    background: #0f766e;
    color: white;
}

.btn {
    display: inline-block;
    background: #0f766e;
    color: white;
    padding: 10px 15px;
    text-decoration: none;
    border-radius: 5px;
    border: none;
    cursor: pointer;
}

.btn:hover {
    background: #115e59;
}

.btn-danger {
    background: #dc2626;
}

.btn-danger:hover {
    background: #b91c1c;
}

.form-group {
    margin-bottom: 15px;
}

label {
    font-weight: bold;
    display: block;
    margin-bottom: 6px;
}

input,
select,
textarea {
    width: 100%;
    padding: 10px;
    border: 1px solid #bbb;
    border-radius: 5px;
}

.login-box {
    width: 400px;
    max-width: 95%;
    margin: 80px auto;
    background: white;
    padding: 25px;
    border-radius: 8px;
    box-shadow: 0 3px 12px rgba(0,0,0,0.12);
}

.alert {
    padding: 12px;
    border-radius: 5px;
    margin-bottom: 15px;
}

.alert-error {
    background: #fee2e2;
    color: #991b1b;
}

.alert-success {
    background: #dcfce7;
    color: #166534;
}

.status-online {
    color: green;
    font-weight: bold;
}

.status-offline {
    color: red;
    font-weight: bold;
}

@media (max-width: 900px) {
    .grid {
        grid-template-columns: repeat(2, 1fr);
    }

    .topbar {
        flex-direction: column;
        gap: 15px;
    }
}

@media (max-width: 600px) {
    .grid {
        grid-template-columns: 1fr;
    }

    .menu a {
        display: block;
        margin: 8px 0;
    }
}