body {
    font-family: Arial, sans-serif;
    margin: 0;
    padding: 0;
    background: #f5f5f5;
}

header {
    background: #2c3e50;
    color: white;
    padding: 1rem;
    text-align: center;
}

h1, h2 {
    margin: 0 0 1rem 0;
}

nav.tabs {
    display: flex;
    background: #34495e;
}

nav.tabs button {
    flex: 1;
    padding: 1rem;
    background: #34495e;
    color: white;
    border: none;
    cursor: pointer;
    font-size: 1rem;
}

nav.tabs button.active {
    background: #1abc9c;
}

main {
    padding: 1rem;
}

.tab {
    display: none;
    background: white;
    padding: 1rem;
    border-radius: 5px;
}

.tab.active {
    display: block;
}

form {
    display: flex;
    flex-direction: column;
    gap: 0.75rem;
}

label {
    display: flex;
    flex-direction: column;
    font-weight: bold;
}

input, textarea, button {
    padding: 0.5rem;
    font-size: 1rem;
    border: 1px solid #ccc;
    border-radius: 4px;
}

fieldset {
    border: 1px solid #ccc;
    padding: 0.75rem;
    border-radius: 4px;
}

legend {
    font-weight: bold;
}

button {
    background: #1abc9c;
    color: white;
    border: none;
    cursor: pointer;
    transition: background 0.2s;
}

button:hover {
    background: #16a085;
}

.batch-entry {
    border: 1px solid #ddd;
    padding: 0.75rem;
    margin-bottom: 0.75rem;
    background: #fafafa;
    border-radius: 4px;
}

@media (max-width: 600px) {
    nav.tabs {
        flex-direction: column;
    }
}