body {
    font-family: Arial, Helvetica, sans-serif;
    background-color: #f0f0f0;
    margin: 0;
    padding: 0;
    font-size: 13px;
    color: #333;
}

.container {
    width: 760px;
    margin: 20px auto;
    background-color: #fff;
    border: 1px solid #ccc;
    padding: 20px;
}

h1, h2, h3 {
    color: #444;
    margin-top: 0;
}

h1 { font-size: 18px; border-bottom: 2px solid #ddd; padding-bottom: 10px; margin-bottom: 20px; }
h2 { font-size: 16px; margin-bottom: 10px; }
h3 { font-size: 14px; margin-bottom: 5px; }

header {
    background-color: #e0e0e0;
    border-bottom: 1px solid #999;
    padding: 10px 20px;
    margin-bottom: 20px;
}

nav a {
    margin-right: 15px;
    color: #0066cc;
    text-decoration: none;
    font-weight: bold;
}

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

table {
    width: 100%;
    border-collapse: collapse;
    margin-bottom: 20px;
    font-size: 12px;
}

table th, table td {
    border: 1px solid #ccc;
    padding: 6px;
    text-align: left;
}

table th {
    background-color: #eee;
    font-weight: bold;
}

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

label {
    display: inline-block;
    width: 100px;
    font-weight: bold;
}

input[type="text"], input[type="password"], input[type="date"] {
    padding: 3px;
    border: 1px solid #999;
}

button {
    padding: 4px 10px;
    background-color: #ddd;
    border: 1px solid #999;
    cursor: pointer;
    font-size: 12px;
}

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

.account-header {
    background-color: #f9f9f9;
    border: 1px solid #ddd;
    padding: 10px;
    margin-bottom: 20px;
}

.filters {
    margin-bottom: 15px;
    padding: 10px;
    background-color: #eee;
    border: 1px solid #ccc;
}

.footer {
    margin-top: 20px;
    font-size: 11px;
    color: #666;
    text-align: center;
    border-top: 1px solid #ddd;
    padding-top: 10px;
}

.error {
    color: red;
    margin-bottom: 10px;
}

/* Bill status colors */
.status-paid { color: green; font-weight: bold; }
.status-unpaid { color: red; font-weight: bold; }

/* Login specific */
.login-box {
    width: 300px;
    margin: 50px auto;
    border: 1px solid #999;
    padding: 20px;
    background-color: #fff;
}