* {
    box-sizing: border-box;
    margin: 0;
    padding: 0;
    font-family: 'Arial', sans-serif;
}

body {
    background: #f5f5f5;
    padding: 2rem;
    min-height: 100vh;
}

.timer-container {
    text-align: center;
    margin-bottom: 2rem;
    padding: 1rem;
    background: #fff;
    border-radius: 8px;
    box-shadow: 0 2px 4px rgba(0, 0, 0, 0.1);
}

#countdown {
    font-size: 2rem;
    color: #e74c3c;
    font-weight: bold;
}

.pricing-container {
    display: flex;
    justify-content: center;
    gap: 2rem;
    flex-wrap: wrap;
    max-width: 1200px;
    margin: 0 auto;
}

.pricing-card {
    background: white;
    border-radius: 10px;
    padding: 2rem;
    width: 300px;
    box-shadow: 0 4px 6px rgba(0, 0, 0, 0.1);
    transition: transform 0.3s ease;
}

.pricing-card:hover {
    transform: translateY(-5px);
}

.price-header {
    text-align: center;
    margin-bottom: 1.5rem;
}

.price {
    font-size: 2.5rem;
    color: #2ecc71;
    margin: 1rem 0;
}

.original-price {
    color: #999;
    text-decoration: line-through;
    font-size: 1.5rem;
    margin-bottom: 0.5rem;
}

.feature-list {
    list-style: none;
    margin: 1.5rem 0;
}

.feature-list li {
    margin: 0.8rem 0;
    padding-left: 2rem;
    position: relative;
}

.feature-list li::before {
    content: "✓";
    color: #2ecc71;
    position: absolute;
    left: 0;
}

.btn {
    display: block;
    width: 100%;
    padding: 1rem;
    background: #2ecc71;
    color: white;
    text-align: center;
    border: none;
    border-radius: 5px;
    text-decoration: none;
    font-weight: bold;
    cursor: pointer;
    transition: all 0.3s ease;
}

.btn:hover {
    background: #27ae60;
    text-decoration: none;
    color: white;
}

.btn.disabled {
    background: #cccccc;
    cursor: not-allowed;
    opacity: 0.7;
    pointer-events: none;
}

.highlight {
    border: 2px solid #2ecc71;
}

.all-topics {
    font-weight: bold;
    color: #2ecc71;
}

.agreement-container {
    margin: 1rem 0;
    display: flex;
    align-items: start;
    gap: 0.5rem;
}

.agreement-container input[type="checkbox"] {
    width: 18px;
    height: 18px;
    cursor: pointer;
    margin-top: 3px;
}

.terms-container {
    display: flex;
    flex-direction: column;
}

.agreement-text {
    font-size: 0.9rem;
    color: #666;
}

.view-terms {
    font-size: 0.7rem;
    color: #2ecc71;
    text-decoration: none;
    margin-top: 2px;
}

.view-terms:hover {
    text-decoration: underline;
}

.error-message {
    color: #e74c3c;
    font-size: 0.9rem;
    margin-top: 0.5rem;
    text-align: center;
    display: none;
}

@media (max-width: 768px) {
    .pricing-card {
        width: 100%;
        max-width: 350px;
    }
}
h1 {
    color: #2c3e50;
    margin-bottom: 1rem;
    font-size: 2.5rem;
}

.subtitle {
    color: #7f8c8d;
    font-size: 1.2rem;
}

.testimonials {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 2rem;
    margin-top: 2rem;
}

.testimonial {
    background: #fff;
    padding: 2rem;
    border-radius: 15px;
    box-shadow: 0 4px 20px rgba(0,0,0,0.1);
    transition: transform 0.3s ease;
}

.testimonial:hover {
    transform: translateY(-5px);
}

.testimonial img {
    width: 150px;
    height: 150px;
    border-radius: 50%;
    margin-bottom: 1rem;
    object-fit: cover;
    border: 5px solid #f0f2f5;
}

.student-info {
    text-align: center;
    margin-bottom: 1.5rem;
}

.student-name {
    color: #2c3e50;
    font-size: 1.25rem;
    font-weight: bold;
    margin-bottom: 0.5rem;
}

.student-grade {
    color: #3498db;
    font-weight: 500;
    margin-bottom: 0.5rem;
}

.quote {
    color: #34495e;
    line-height: 1.6;
    font-style: italic;
    position: relative;
    padding: 0 1rem;
}

.quote::before, .quote::after {
    content: '"';
    font-size: 2rem;
    color: #3498db;
    position: absolute;
}

.quote::before {
    left: -5px;
    top: -10px;
}

.quote::after {
    right: -5px;
    bottom: -10px;
}

.improvement {
    margin-top: 1rem;
    padding: 0.5rem;
    background: #e8f4fc;
    border-radius: 5px;
    color: #2980b9;
    font-weight: 500;
}

@media (max-width: 768px) {
    .container {
        padding: 1rem;
    }

    h1 {
        font-size: 2rem;
    }

    .testimonial {
        padding: 1.5rem;
    }
}

.fade-in {
    opacity: 0;
    transform: translateY(20px);
    animation: fadeIn 0.8s ease forwards;
}

@keyframes fadeIn {
    to {
        opacity: 1;
        transform: translateY(0);
    }
}