* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

body {
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    min-height: 100vh;
    padding: 20px;
}

.container {
    max-width: 600px;
    margin: 0 auto;
}

header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 30px;
    padding: 20px;
    background: rgba(255, 255, 255, 0.1);
    border-radius: 15px;
    backdrop-filter: blur(10px);
}

header h1 {
    color: white;
    font-size: 1.8rem;
    font-weight: 600;
}

.logout-btn {
    background: #ff6b6b;
    color: white;
    border: none;
    padding: 10px 20px;
    border-radius: 8px;
    cursor: pointer;
    font-weight: 600;
    transition: all 0.3s ease;
}

.logout-btn:hover {
    background: #ee5a5a;
    transform: translateY(-2px);
}

.auth-card, .task-input-card, .tasks-card {
    background: white;
    border-radius: 20px;
    padding: 30px;
    margin-bottom: 20px;
    box-shadow: 0 10px 40px rgba(0, 0, 0, 0.2);
}

.auth-card {
    text-align: center;
}

.auth-card h2 {
    color: #333;
    margin-bottom: 10px;
    font-size: 1.8rem;
}

.subtitle {
    color: #888;
    margin-bottom: 25px;
}

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

.form-group input {
    width: 100%;
    padding: 15px;
    border: 2px solid #eee;
    border-radius: 10px;
    font-size: 1rem;
    transition: border-color 0.3s ease;
}

.form-group input:focus {
    outline: none;
    border-color: #667eea;
}

.auth-buttons {
    display: flex;
    gap: 10px;
    margin-top: 20px;
}

.btn {
    flex: 1;
    padding: 15px 25px;
    border: none;
    border-radius: 10px;
    font-size: 1rem;
    font-weight: 600;
    cursor: pointer;
    transition: all 0.3s ease;
}

.btn-primary {
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
}

.btn-primary:hover {
    transform: translateY(-2px);
    box-shadow: 0 5px 20px rgba(102, 126, 234, 0.4);
}

.btn-secondary {
    background: #f0f0f0;
    color: #333;
}

.btn-secondary:hover {
    background: #e0e0e0;
}

.task-input-card h3, .tasks-card h3 {
    color: #333;
    margin-bottom: 20px;
    font-size: 1.3rem;
}

.task-form {
    display: flex;
    gap: 10px;
    flex-wrap: wrap;
}

.task-form input {
    flex: 2;
    min-width: 200px;
    padding: 12px 15px;
    border: 2px solid #eee;
    border-radius: 10px;
    font-size: 1rem;
}

.task-form input:focus {
    outline: none;
    border-color: #667eea;
}

.task-form select {
    flex: 1;
    min-width: 140px;
    padding: 12px 15px;
    border: 2px solid #eee;
    border-radius: 10px;
    font-size: 1rem;
    background: white;
    cursor: pointer;
}

.task-form select:focus {
    outline: none;
    border-color: #667eea;
}

.task-form .btn {
    flex: 0 0 auto;
}

#taskList {
    list-style: none;
}

.task-item {
    display: flex;
    align-items: center;
    gap: 15px;
    padding: 15px;
    margin-bottom: 10px;
    background: #f8f9fa;
    border-radius: 12px;
    border-left: 4px solid #667eea;
    transition: all 0.3s ease;
}

.task-item:hover {
    transform: translateX(5px);
    box-shadow: 0 3px 15px rgba(0, 0, 0, 0.1);
}

.task-item.priority-high {
    border-left-color: #ff6b6b;
    background: #fff5f5;
}

.task-item.priority-medium {
    border-left-color: #feca57;
    background: #fffbf0;
}

.task-item.priority-low {
    border-left-color: #5cd85c;
    background: #f0fff0;
}

.task-item.completed {
    opacity: 0.6;
    background: #e9ecef;
}

.task-item.completed .task-text {
    text-decoration: line-through;
    color: #888;
}

.task-checkbox {
    width: 22px;
    height: 22px;
    cursor: pointer;
    accent-color: #667eea;
}

.task-content {
    flex: 1;
    display: flex;
    flex-direction: column;
    gap: 5px;
}

.task-text {
    font-size: 1rem;
    color: #333;
}

.task-priority {
    font-size: 0.75rem;
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 0.5px;
}

.priority-high .task-priority {
    color: #ff6b6b;
}

.priority-medium .task-priority {
    color: #feca57;
}

.priority-low .task-priority {
    color: #5cd85c;
}

.delete-btn {
    background: #ff6b6b;
    color: white;
    border: none;
    padding: 8px 15px;
    border-radius: 8px;
    cursor: pointer;
    font-size: 0.85rem;
    font-weight: 600;
    transition: all 0.3s ease;
}

.delete-btn:hover {
    background: #ee5a5a;
    transform: scale(1.05);
}

.empty-message {
    text-align: center;
    color: #888;
    padding: 30px;
    font-style: italic;
}

@media (max-width: 500px) {
    header {
        flex-direction: column;
        gap: 15px;
        text-align: center;
    }

    .task-form {
        flex-direction: column;
    }

    .task-form input,
    .task-form select,
    .task-form .btn {
        width: 100%;
    }

    .auth-buttons {
        flex-direction: column;
    }
}