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

body {
    font-family: 'Comic Sans MS', 'Chalkboard SE', 'Comic Neue', cursive, sans-serif;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    min-height: 100vh;
    padding: 0;
    margin: 0;
    color: #333;
}

.app-wrapper {
    display: flex;
    min-height: 100vh;
    gap: 20px;
    padding: 20px;
}

.sidebar {
    width: 280px;
    background: white;
    border-radius: 20px;
    padding: 20px;
    box-shadow: 0 10px 40px rgba(0, 0, 0, 0.2);
    position: sticky;
    top: 20px;
    height: fit-content;
    max-height: calc(100vh - 40px);
    overflow-y: auto;
}

.sidebar-item {
    padding: 15px;
    margin-bottom: 10px;
    border-radius: 10px;
    cursor: pointer;
    transition: all 0.3s ease;
    background: linear-gradient(135deg, #a8edea 0%, #fed6e3 100%);
    border: 2px solid transparent;
}

.sidebar-item:hover {
    transform: translateX(5px);
    box-shadow: 0 4px 10px rgba(0, 0, 0, 0.15);
}

.sidebar-item.active {
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
    border-color: rgba(255, 255, 255, 0.3);
    box-shadow: 0 4px 15px rgba(102, 126, 234, 0.4);
}

.sidebar-item-title {
    font-size: 1.1em;
    font-weight: bold;
    margin-bottom: 5px;
}

.main-content {
    flex: 1;
    min-width: 0;
}

.container {
    max-width: 100%;
    background: white;
    border-radius: 20px;
    padding: 30px;
    box-shadow: 0 10px 40px rgba(0, 0, 0, 0.2);
}

header {
    text-align: center;
    margin-bottom: 30px;
}

h1 {
    font-size: 2.5em;
    color: #667eea;
    margin-bottom: 20px;
    text-shadow: 2px 2px 4px rgba(0, 0, 0, 0.1);
}

.points-display {
    background: linear-gradient(135deg, #f093fb 0%, #f5576c 100%);
    padding: 20px;
    border-radius: 15px;
    color: white;
    box-shadow: 0 5px 15px rgba(0, 0, 0, 0.2);
}

.points-label {
    font-size: 1.2em;
    margin-bottom: 10px;
}

.points-value {
    font-size: 3em;
    font-weight: bold;
    text-shadow: 2px 2px 4px rgba(0, 0, 0, 0.2);
}

.progress-section {
    margin-bottom: 30px;
    text-align: center;
}

.progress-label {
    font-size: 1.3em;
    color: #667eea;
    margin-bottom: 10px;
    font-weight: bold;
}

.progress-bar-container {
    width: 100%;
    height: 30px;
    background: #e0e0e0;
    border-radius: 15px;
    overflow: hidden;
    margin-bottom: 10px;
    box-shadow: inset 0 2px 5px rgba(0, 0, 0, 0.1);
}

.progress-bar {
    height: 100%;
    background: linear-gradient(90deg, #4facfe 0%, #00f2fe 100%);
    width: 0%;
    transition: width 0.5s ease;
    border-radius: 15px;
    box-shadow: 0 2px 5px rgba(0, 0, 0, 0.2);
}

.progress-text {
    font-size: 1.1em;
    color: #666;
    font-weight: bold;
}

.task-section {
    margin-top: 30px;
}

.chapter-description {
    background: linear-gradient(135deg, #e8f5e9 0%, #fff3e0 100%);
    padding: 20px;
    border-radius: 15px;
    margin-bottom: 25px;
    font-size: 1.1em;
    line-height: 1.6;
    color: #555;
    border-left: 4px solid #667eea;
    box-shadow: 0 2px 8px rgba(0, 0, 0, 0.1);
}

.task-container {
    display: grid;
    gap: 20px;
}

.task-card {
    background: linear-gradient(135deg, #a8edea 0%, #fed6e3 100%);
    padding: 25px;
    border-radius: 15px;
    box-shadow: 0 5px 15px rgba(0, 0, 0, 0.1);
    transition: transform 0.2s, box-shadow 0.2s, opacity 0.5s ease, transform 0.5s ease;
    position: relative;
    overflow: hidden;
}

.task-card:hover {
    transform: translateY(-3px);
    box-shadow: 0 8px 20px rgba(0, 0, 0, 0.15);
}

.task-card.confetti-animation {
    animation: confettiFadeOut 1.5s ease forwards;
}

@keyframes confettiFadeOut {
    0% {
        transform: scale(1) rotate(0deg);
        opacity: 1;
    }
    50% {
        transform: scale(1.1) rotate(5deg);
        opacity: 0.8;
    }
    100% {
        transform: scale(0) rotate(10deg);
        opacity: 0;
    }
}

.confetti {
    position: absolute;
    width: 10px;
    height: 10px;
    background: #ffd700;
    animation: confettiFall linear forwards;
    z-index: 1000;
    pointer-events: none;
}

@keyframes confettiFall {
    0% {
        transform: translateY(0) translateX(0) rotate(0deg);
        opacity: 1;
    }
    100% {
        transform: translateY(400px) translateX(calc(var(--random-x, 0) * 100px)) rotate(720deg);
        opacity: 0;
    }
}

.task-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 15px;
}

.task-title {
    font-size: 1.3em;
    font-weight: bold;
    color: #333;
}

.task-points {
    background: #ffd700;
    color: #333;
    padding: 5px 15px;
    border-radius: 20px;
    font-weight: bold;
    font-size: 1.1em;
    box-shadow: 0 2px 5px rgba(0, 0, 0, 0.2);
}

.task-question {
    font-size: 1.5em;
    text-align: center;
    margin: 20px 0;
    color: #333;
    font-weight: bold;
    white-space: pre-line;
}

.task-input-group {
    display: flex;
    gap: 10px;
    align-items: center;
    justify-content: center;
    margin-bottom: 15px;
}

.task-input {
    font-size: 1.5em;
    padding: 10px 15px;
    border: 3px solid #667eea;
    border-radius: 10px;
    width: 120px;
    text-align: center;
    font-family: 'Comic Sans MS', cursive;
    font-weight: bold;
}

.task-input:focus {
    outline: none;
    border-color: #764ba2;
    box-shadow: 0 0 10px rgba(102, 126, 234, 0.3);
}

.task-button {
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
    border: none;
    padding: 12px 25px;
    font-size: 1.2em;
    border-radius: 10px;
    cursor: pointer;
    font-family: 'Comic Sans MS', cursive;
    font-weight: bold;
    transition: transform 0.2s, box-shadow 0.2s;
    box-shadow: 0 4px 10px rgba(0, 0, 0, 0.2);
}

.task-button:hover {
    transform: translateY(-2px);
    box-shadow: 0 6px 15px rgba(0, 0, 0, 0.3);
}

.task-button:active {
    transform: translateY(0);
}

.task-button:disabled {
    background: #ccc;
    cursor: not-allowed;
    transform: none;
}

.task-status {
    text-align: center;
    font-size: 1.1em;
    font-weight: bold;
    margin-top: 10px;
    min-height: 25px;
}

.task-status.success {
    color: #4caf50;
}

.task-status.error {
    color: #f44336;
}

.task-status.completed {
    color: #ff9800;
}

.message {
    position: fixed;
    top: 20px;
    right: 20px;
    padding: 15px 25px;
    border-radius: 10px;
    font-weight: bold;
    font-size: 1.2em;
    box-shadow: 0 5px 15px rgba(0, 0, 0, 0.3);
    transform: translateX(400px);
    transition: transform 0.3s ease;
    z-index: 1000;
}

.message.show {
    transform: translateX(0);
}

.message.success {
    background: #4caf50;
    color: white;
}

.message.error {
    background: #f44336;
    color: white;
}

@media (max-width: 900px) {
    .app-wrapper {
        flex-direction: column;
        padding: 10px;
    }
    
    .sidebar {
        width: 100%;
        position: relative;
        top: 0;
        max-height: none;
        display: flex;
        gap: 10px;
        overflow-x: auto;
        overflow-y: hidden;
        padding: 15px;
    }
    
    .sidebar-item {
        min-width: 200px;
        margin-bottom: 0;
    }
}

@media (max-width: 600px) {
    .container {
        padding: 20px;
    }
    
    h1 {
        font-size: 2em;
    }
    
    .points-value {
        font-size: 2.5em;
    }
    
    .task-input-group {
        flex-direction: column;
    }
    
    .task-button {
        width: 100%;
    }
    
    .sidebar {
        padding: 10px;
    }
    
    .sidebar-item {
        min-width: 180px;
        padding: 12px;
    }
    
    .sidebar-item-title {
        font-size: 1em;
    }
}