body {
    font-family: 'Tahoma', sans-serif;
    background: #f4f6f9;
    margin: 0;
    padding: 0;
    direction: rtl;
}
header {
    background: #004b6b;
    color: white;
    padding: 1rem;
    text-align: center;
}
nav button {
    margin: 0.3rem;
    padding: 0.5rem 1rem;
    border: none;
    background: #007b9e;
    color: white;
    border-radius: 5px;
    cursor: pointer;
}
nav button:hover {
    background: #005f73;
}
main {
    padding: 1rem;
}
.tab {
    margin-top: 1rem;
    padding: 1rem;
    background: white;
    border-radius: 8px;
    box-shadow: 0 2px 5px rgba(0,0,0,0.1);
}
.hidden { display: none; }
form input, form button {
    display: block;
    margin: 0.5rem 0;
    padding: 0.5rem;
    width: 100%;
    max-width: 400px;
}
form button {
    background: #28a745;
    color: white;
    border: none;
    border-radius: 5px;
    cursor: pointer;
}
form button:hover {
    background: #218838;
}