:root {
    --primary-color: #3498db;
    --secondary-color: #2c3e50;
    --accent-color: #e74c3c;
    --bg-color: #f4f7f6;
    --text-color: #333;
    --card-bg: #fff;
    --shadow: 0 4px 6px rgba(0,0,0,0.1);
}

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

header {
    background-color: var(--secondary-color);
    color: white;
    padding: 1rem 0;
    text-align: center;
    box-shadow: var(--shadow);
}

main {
    margin: 2rem auto;
    padding: 0 1rem;
}

.card {
    background-color: var(--card-bg);
    padding: 2rem;
    border-radius: 8px;
    box-shadow: var(--shadow);
}

table {
    width: 100%;
    border-collapse: collapse;
    margin: 1.5rem 0;
}

th, td {
    padding: 12px 15px;
    text-align: left;
    border-bottom: 1px solid #ddd;
}

th {
    background-color: #f2f2f2;
    font-weight: bold;
}

tr:hover {
    background-color: #f9f9f9;
}

.btn {
    display: inline-block;
    padding: 8px 16px;
    border-radius: 4px;
    text-decoration: none;
    font-weight: 500;
    cursor: pointer;
    border: none;
    transition: background 0.3s;
}

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

.btn-primary:hover {
    background-color: #2980b9;
}

.btn-danger {
    background-color: var(--accent-color);
    color: white;
}

.btn-danger:hover {
    background-color: #c0392b;
}

form div {
    margin-bottom: 1rem;
}

label {
    display: block;
    margin-bottom: 0.5rem;
    font-weight: 600;
}

input[type="text"], input[type="datetime-local"] {
    width: 100%;
    padding: 10px;
    border: 1px solid #ccc;
    border-radius: 4px;
    box-sizing: border-box;
}