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

body {
    font-family: 'Arial', sans-serif;
    background: linear-gradient(135deg, #546e7a 0%, #37474f 100%);
    min-height: 100vh;
    display: flex;
    justify-content: center;
    align-items: center;
    padding: 20px;
    overflow-x: hidden;
}

.container {
    background: white;
    border-radius: 20px;
    padding: 40px;
    box-shadow: 0 20px 60px rgba(0, 0, 0, 0.3);
    max-width: 1000px;
    width: 100%;
    position: relative;
}

h1 {
    color: #333;
    text-align: center;
    margin-bottom: 25px;
    font-size: 32px;
}

/* Story Box */
.story-box {
    background: linear-gradient(135deg, #e0f2f1 0%, #b2dfdb 100%);
    border-left: 5px solid #00897b;
    padding: 25px;
    border-radius: 10px;
    margin-bottom: 30px;
}

.story-header {
    display: flex;
    align-items: center;
    gap: 15px;
    margin-bottom: 15px;
}

.icon {
    font-size: 50px;
    animation: float 3s ease-in-out infinite;
}

@keyframes float {
    0%, 100% { transform: translateY(0); }
    50% { transform: translateY(-10px); }
}

.header-text strong {
    color: #004d40;
    font-size: 20px;
    display: block;
}

.header-text p {
    color: #666;
    font-size: 14px;
    margin-top: 3px;
}

.story-text {
    color: #333;
    line-height: 1.8;
    font-size: 18px;
    text-align: center;
}

/* Wiper Section */
.wiper-section {
    margin: 40px 0;
    display: flex;
    justify-content: center;
}

.wiper-container {
    background: linear-gradient(135deg, #eceff1 0%, #cfd8dc 100%);
    border: 3px solid #546e7a;
    border-radius: 20px;
    padding: 30px;
    box-shadow: 0 10px 30px rgba(0, 0, 0, 0.2);
}

.wiper-svg {
    width: 100%;
    max-width: 500px;
    height: auto;
    display: block;
}

.wiper-left {
    animation: wipe-left 3s ease-in-out infinite;
    transform-origin: 250px 380px;
}

.wiper-right {
    animation: wipe-right 3s ease-in-out infinite;
    transform-origin: 250px 380px;
}

@keyframes wipe-left {
    0%, 100% { opacity: 1; }
    50% { opacity: 0.3; }
}

@keyframes wipe-right {
    0%, 100% { opacity: 0.3; }
    50% { opacity: 1; }
}

/* Info Section */
.info-section {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 20px;
    margin: 30px 0;
}

.info-box {
    background: linear-gradient(135deg, #fff3e0 0%, #ffe0b2 100%);
    border: 3px solid #ff9800;
    border-radius: 15px;
    padding: 20px;
}

.info-label {
    font-size: 18px;
    font-weight: bold;
    color: #e65100;
    margin-bottom: 12px;
    padding-bottom: 10px;
    border-bottom: 2px solid #ff9800;
}

.info-content {
    display: flex;
    flex-direction: column;
    gap: 10px;
}

.info-item {
    font-size: 16px;
    color: #333;
}

.value {
    color: #d84315;
    font-weight: bold;
    font-size: 18px;
}

.formula-text {
    font-family: 'Courier New', monospace;
    font-size: 18px;
    color: #1565c0;
    font-weight: bold;
}

/* Question Section */
.question-section {
    margin: 30px 0;
}

.question-label {
    font-size: 20px;
    font-weight: bold;
    color: #333;
    text-align: center;
    margin-bottom: 15px;
    padding: 20px;
    background: linear-gradient(135deg, #f3e5f5 0%, #e1bee7 100%);
    border-radius: 10px;
    border-left: 5px solid #9c27b0;
}

.question-text {
    font-size: 18px;
    color: #555;
    text-align: center;
    margin-bottom: 25px;
}

/* Input Container */
.input-container {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 15px;
    margin: 30px 0;
    padding: 25px;
    background: linear-gradient(135deg, #fff9c4 0%, #fff59d 100%);
    border-radius: 15px;
    border: 3px solid #fbc02d;
    flex-wrap: wrap;
}

.input-label {
    font-size: 24px;
    font-weight: bold;
    color: #f57f17;
}

.answer-input {
    min-width: 200px;
    max-width: 300px;
    padding: 15px 20px;
    font-size: 24px;
    font-weight: bold;
    border: 3px solid #1976d2;
    border-radius: 10px;
    text-align: center;
    outline: none;
    transition: all 0.3s ease;
}

.answer-input:focus {
    border-color: #0d47a1;
    box-shadow: 0 0 10px rgba(25, 118, 210, 0.3);
}

.input-unit {
    font-size: 24px;
    font-weight: bold;
    color: #f57f17;
}

.check-btn {
    background: #1976d2;
    color: white;
    border: none;
    padding: 15px 35px;
    border-radius: 10px;
    font-size: 18px;
    font-weight: bold;
    cursor: pointer;
    transition: all 0.3s ease;
}

.check-btn:hover {
    background: #0d47a1;
    transform: translateY(-2px);
    box-shadow: 0 5px 15px rgba(25, 118, 210, 0.4);
}

.check-btn:active {
    transform: translateY(0);
}

.check-btn:disabled {
    background: #9e9e9e;
    cursor: not-allowed;
    transform: none;
}

/* Feedback */
.feedback {
    text-align: center;
    font-size: 20px;
    font-weight: bold;
    min-height: 30px;
    margin-top: 20px;
    padding: 15px;
    border-radius: 10px;
}

.feedback.success {
    color: #4caf50;
    background: linear-gradient(135deg, #c8e6c9 0%, #a5d6a7 100%);
}

.feedback.error {
    color: #f44336;
    background: linear-gradient(135deg, #ffcdd2 0%, #ef9a9a 100%);
}

/* Reset Button */
.reset-btn {
    display: block;
    margin: 20px auto;
    background: #4caf50;
    color: white;
    border: none;
    padding: 15px 40px;
    border-radius: 10px;
    font-size: 16px;
    font-weight: bold;
    cursor: pointer;
    transition: all 0.3s ease;
}

.reset-btn:hover {
    background: #388e3c;
    transform: translateY(-2px);
    box-shadow: 0 5px 15px rgba(76, 175, 80, 0.4);
}

.reset-btn:active {
    transform: translateY(0);
}

/* Clapping Animation */
.clapping-container {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    pointer-events: none;
    z-index: 9999;
    display: none;
}

.clapping-container.active {
    display: block;
}

.clap-emoji {
    position: absolute;
    font-size: 60px;
    animation: clapping 1.5s ease-out forwards;
    opacity: 0;
}

.clap-emoji:nth-child(1) { top: 20%; left: 15%; animation-delay: 0s; }
.clap-emoji:nth-child(2) { top: 30%; left: 25%; animation-delay: 0.1s; }
.clap-emoji:nth-child(3) { top: 40%; left: 35%; animation-delay: 0.2s; }
.clap-emoji:nth-child(4) { top: 50%; left: 45%; animation-delay: 0.3s; }
.clap-emoji:nth-child(5) { top: 60%; left: 55%; animation-delay: 0.4s; }
.clap-emoji:nth-child(6) { top: 25%; right: 15%; animation-delay: 0.5s; }
.clap-emoji:nth-child(7) { top: 35%; right: 25%; animation-delay: 0.6s; }
.clap-emoji:nth-child(8) { top: 45%; right: 35%; animation-delay: 0.7s; }
.clap-emoji:nth-child(9) { top: 55%; right: 45%; animation-delay: 0.8s; }
.clap-emoji:nth-child(10) { top: 65%; right: 55%; animation-delay: 0.9s; }

@keyframes clapping {
    0% {
        opacity: 0;
        transform: scale(0) rotate(0deg);
    }
    50% {
        opacity: 1;
        transform: scale(1.2) rotate(15deg);
    }
    100% {
        opacity: 0;
        transform: scale(0.8) rotate(-15deg);
    }
}

/* Responsive */
@media (max-width: 968px) {
    .info-section {
        grid-template-columns: 1fr;
    }
}

@media (max-width: 768px) {
    .container {
        padding: 25px;
    }

    h1 {
        font-size: 26px;
    }

    .wiper-svg {
        max-width: 380px;
    }

    .question-label {
        font-size: 18px;
    }

    .answer-input {
        min-width: 150px;
        font-size: 20px;
    }

    .input-container {
        flex-wrap: wrap;
    }
}

@media (max-width: 480px) {
    .container {
        padding: 20px;
    }

    h1 {
        font-size: 22px;
    }

    .story-text {
        font-size: 16px;
    }

    .wiper-svg {
        max-width: 300px;
    }

    .question-label {
        font-size: 16px;
    }

    .answer-input {
        min-width: 120px;
        font-size: 18px;
        padding: 12px 15px;
    }

    .input-label, .input-unit {
        font-size: 20px;
    }

    .check-btn {
        padding: 12px 25px;
        font-size: 16px;
    }

    .feedback {
        font-size: 18px;
    }
}