:root {
    --bg: #f5f7fa;
    --card: #ffffff;
    --text: #1f2937;
    --sidebar: #1e293b;
    --sidebar-text: #ffffff;
    --accent: #2563eb;
    --border: #d1d5db;
}

body.dark {
    --bg: #111827;
    --card: #1f2937;
    --text: #f9fafb;
    --sidebar: #0f172a;
    --sidebar-text: #ffffff;
    --accent: #3b82f6;
    --border: #374151;
}

body {
    margin: 0;
    font-family: Arial, sans-serif;
    background: var(--bg);
    color: var(--text);
}

.app {
    display: flex;
    height: 100vh;
}

.sidebar {
    width: 220px;
    background: var(--sidebar);
    color: var(--sidebar-text);
    padding: 24px;
}

.sidebar h2 {
    margin-bottom: 32px;
}

.sidebar nav {
    display: flex;
    flex-direction: column;
    gap: 16px;
}

.sidebar a {
    color: var(--sidebar-text);
    text-decoration: none;
    font-weight: 500;
}

.main-content {
    flex: 1;
    display: flex;
    flex-direction: column;
}

.header {
    background: var(--card);
    padding: 20px 32px;
    border-bottom: 1px solid var(--border);
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.content {
    padding: 32px;
    display: flex;
    gap: 24px;
    flex-wrap: wrap;
}

.card {
    background: var(--card);
    padding: 24px;
    border-radius: 12px;
    box-shadow: 0 4px 10px rgba(0,0,0,0.05);
    min-width: 320px;
    flex: 1;
}

input, select {
    width: 100%;
    padding: 10px;
    margin: 8px 0 16px;
    border: 1px solid var(--border);
    border-radius: 8px;
    background: transparent;
    color: var(--text);
}

button {
    background: var(--accent);
    color: white;
    border: none;
    padding: 10px 18px;
    border-radius: 8px;
    cursor: pointer;
}

button:hover {
    opacity: 0.9;
}

table {
    width: 100%;
    border-collapse: collapse;
    margin-top: 12px;
}

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

th {
    background: rgba(0,0,0,0.03);
}