/* Reset default margins and ensure box-sizing */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

body {
    font-family: Arial, sans-serif;
    background-color: #f4f4f4;
    padding: 2%; /* Relative padding */
    line-height: 1.6;
}

header {
    background-color: #333;
    color: white;
    padding: 1rem;
    text-align: center;
}

header h1 {
    font-size: 1.5rem; /* Scales with screen */
}

nav {
    margin-top: 1rem;
}

nav a {
    color: white;
    text-decoration: none;
    padding: 0.5rem 1rem;
    display: inline-block; /* Allows stacking on small screens */
}

nav a:hover {
    text-decoration: underline;
}

main {
    width: 90%; /* Fluid width */
    max-width: 800px; /* Retains max limit */
    margin: 2rem auto;
    background: white;
    padding: 1.5rem;
    border-radius: 5px;
    box-shadow: 0 0 10px rgba(0,0,0,0.1);
}

h2 {
    color: #333;
    font-size: 1.25rem;
    margin-bottom: 1rem;
}

table {
    width: 100%;
    border-collapse: collapse;
    margin-top: 1rem;
}

table, th, td {
    border: 1px solid #ddd;
}

th, td {
    padding: 0.75rem;
    text-align: left;
    font-size: 0.9rem; /* Slightly smaller for mobile */
}

th {
    background-color: #f2f2f2;
}

form label {
    display: block;
    margin: 1rem 0;
    font-size: 0.9rem;
}

input[type="text"], 
input[type="password"], 
input[type="number"] {
    padding: 0.5rem;
    width: 100%; /* Full width for responsiveness */
    max-width: 300px; /* Limits width on larger screens */
    font-size: 1rem;
}

input[type="submit"], 
button {
    padding: 0.75rem 1.5rem;
    background-color: #4CAF50; /* Green for submit */
    color: white;
    border: none;
    cursor: pointer;
    margin-top: 1rem;
    font-size: 1rem;
}

input[type="submit"]:hover {
    background-color: #45a049;
}

button {
    background-color: #ff4444; /* Red for remove */
    padding: 0.5rem 1rem;
}

button:hover {
    background-color: #cc0000;
}

.error {
    color: red;
    font-size: 0.9rem;
    margin-top: 1rem;
}

.success {
    color: green;
    font-size: 0.9rem;
    margin-top: 1rem;
}

/* Media Queries for Mobile */
@media (max-width: 600px) {
    header h1 {
        font-size: 1.2rem;
    }

    nav a {
        display: block; /* Stack nav links vertically */
        padding: 0.5rem;
    }

    main {
        width: 95%;
        padding: 1rem;
    }

    th, td {
        padding: 0.5rem;
        font-size: 0.8rem;
    }

    input[type="text"], 
    input[type="password"], 
    input[type="number"] {
        max-width: 100%; /* Full width on small screens */
    }

    input[type="submit"], 
    button {
        width: 100%; /* Full width buttons */
        padding: 0.75rem;
    }
}

/* Ensure tables are scrollable on small screens if DataTables isn't responsive */
@media (max-width: 600px) {
    table {
        display: block;
        overflow-x: auto;
        white-space: nowrap;
    }
}