:root {
    --bg-color: #f5f5f5;
    --card-bg: #fff;
    --text-color: #222;
    --header-color: #2c3e50;
    --subheader-color: #34495e;
    --border-color: #ddd;
    --primary-btn-bg: #333;
    --primary-btn-hover: #111;
    --delete-btn-bg: #e74c3c;
    --delete-btn-hover: #c0392b;
    --revoke-btn-bg: #f39c12;
    --revoke-btn-hover: #d35400;
    --create-btn-bg: #16ff00;
    --create-btn-hover: #0b9f00;
    --font-family: system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
}

@media (prefers-color-scheme: dark) {
    :root {
        --bg-color: #181818;
        --card-bg: #242424;
        --text-color: #eee;
        --header-color: #ecf0f1;
        --subheader-color: #bdc3c7;
        --border-color: #3a3a3a;
        --primary-btn-bg: #e5e5e5;
        --primary-btn-hover: #fff;
    }
}

* {
    box-sizing: border-box;
}

body {
    margin: 0;
    padding: 20px;
    font-family: var(--font-family);
    background-color: var(--bg-color);
    color: var(--text-color);
    line-height: 1.5;
}

h1 {
    color: var(--header-color);
    text-align: center;
    margin-bottom: 30px;
}

h2 {
    color: var(--subheader-color);
    border-bottom: 2px solid var(--border-color);
    padding-bottom: 10px;
    margin-top: 0;
    margin-bottom: 1.5rem;
}

button {
    padding: 8px 12px;
    border: none;
    border-radius: 4px;
    cursor: pointer;
    font-family: inherit;
    font-weight: 600;
    transition: background-color 0.2s;
    font-size: 0.9em;
}

button:disabled {
    pointer-events: none;
    opacity: 0.8;
}

.btn-primary {
    background-color: var(--primary-btn-bg);
    color: var(--bg-color);
}

.btn-primary:hover {
    background-color: var(--primary-btn-hover);
}

.btn-delete {
    background-color: var(--delete-btn-bg);
    color: white;
}

.btn-delete:not(:disabled):hover {
    background-color: var(--delete-btn-hover);
}

.btn-revoke {
    background-color: var(--revoke-btn-bg);
    color: white;
}

.btn-revoke:not(:disabled):hover {
    background-color: var(--revoke-btn-hover);
}

.btn-create {
    background-color: var(--create-btn-bg);
}

.btn-create:not(:disabled):hover {
    background-color: var(--create-btn-hover);
}

table {
    width: 100%;
    border-collapse: collapse;
    margin-top: 10px;
}

th, td {
    text-align: left;
    padding: 12px;
    border-bottom: 1px solid var(--border-color);
}

th {
    background-color: rgba(0,0,0,0.05);
    font-weight: 600;
}

tr:hover {
    background-color: rgba(0,0,0,0.02);
}

.card, .table-section {
    background: var(--card-bg);
    padding: 20px;
    border-radius: 8px;
    box-shadow: 0 2px 4px rgba(0,0,0,0.1);
    border: 1px solid var(--border-color);
}