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

.calendar-container {
    max-width: 1200px;
    margin: 20px auto;
    background: #fff;
    padding: 20px;
    border-radius: 8px;
    box-shadow: 0 4px 6px rgba(0, 0, 0, 0.1);
}

.calendar-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 20px;
}

.calendar-header h1 {
    font-size: 1.5rem;
    margin: 0;
}

.calendar-header button {
    padding: 10px 15px;
    background-color: #007bff;
    color: #fff;
    border: none;
    border-radius: 5px;
    cursor: pointer;
}

.calendar-header button:hover {
    background-color: #0056b3;
}

.calendar-grid {
    display: grid;
    grid-template-columns: repeat(7, 1fr);
    gap: 5px;
}

.day {
    border: 1px solid #ddd;
    border-radius: 5px;
    padding: 10px;
    background-color: #f9f9f9;
    min-height: 100px;
    position: relative;
}

.day-header {
    font-weight: bold;
    margin-bottom: 10px;
}

.task {
    font-size: 0.9rem;
    background-color: #d4edda;
    color: #155724;
    border: 1px solid #c3e6cb;
    border-radius: 5px;
    padding: 5px;
    margin-bottom: 5px;
}

.task.urgent {
    background-color: #f8d7da;
    color: #721c24;
    border: 1px solid #f5c6cb;
}

.task.in-progress {
    background-color: #ffeeba;
    color: #856404;
    border: 1px solid #ffeeba;
}

.filter-section {
    margin-bottom: 20px;
    display: flex;
    gap: 10px;
    align-items: center;
}

.filter-section input, .filter-section button {
    padding: 10px;
    font-size: 1rem;
    border: 1px solid #ccc;
    border-radius: 5px;
}

.filter-section button {
    background-color: #28a745;
    color: #fff;
    cursor: pointer;
}

.filter-section button:hover {
    background-color: #218838;
}

#addTaskModal {
    display: none;
    position: fixed;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    background-color: #fff;
    padding: 30px;
    box-shadow: 0 8px 16px rgba(0, 0, 0, 0.2);
    border-radius: 12px;
    z-index: 1000;
    animation: fadeIn 0.3s ease;
}

#addTaskModal form {
    display: flex;
    flex-direction: column;
    gap: 15px;
}

#addTaskModal form input, #addTaskModal form select, #addTaskModal form button {
    padding: 12px;
    font-size: 1rem;
    border: 1px solid #ccc;
    border-radius: 8px;
}

#addTaskModal form button {
    background-color: #007bff;
    color: #fff;
    cursor: pointer;
    font-weight: bold;
}

#addTaskModal form button:hover {
    background-color: #0056b3;
}

#modalOverlay {
    display: none;
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: rgba(0, 0, 0, 0.5);
    z-index: 999;
}

#modalOverlay.show, #addTaskModal.show {
    display: block;
}

.sub-tasks-container {
    background-color: #f9f9f9;
    border-left: 2px solid #007bff;
    padding-left: 10px;
    margin-top: 10px;
}

@keyframes fadeIn {
    from {
        opacity: 0;
    }
    to {
        opacity: 1;
    }
}