:root {
    --primary-color: #2196F3;
    --secondary-color: #1976D2;
    --background-color: #f8f9fa;
    --text-color: #2c3e50;
    --card-bg: #ffffff;
    --accent-color: #FF4081;
    --border-radius: 12px;
    --shadow: 0 4px 20px rgba(0, 0, 0, 0.08);
}

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

@keyframes fadeIn {
    from { opacity: 0; transform: translateY(20px); }
    to { opacity: 1; transform: translateY(0); }
}

@keyframes pulse {
    0% { transform: scale(1); }
    50% { transform: scale(1.02); }
    100% { transform: scale(1); }
}

@keyframes slideIn {
    from { transform: translateX(-100%); opacity: 0; }
    to { transform: translateX(0); opacity: 1; }
}

body {
    font-family: 'Arial', sans-serif;
    background-color: var(--background-color);
    color: var(--text-color);
    line-height: 1.8;
    font-size: 16px;
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 2rem;
    animation: fadeIn 1s ease-out;
}

.hero-section {
    text-align: center;
    padding: 4rem 2rem;
    background: linear-gradient(135deg, var(--primary-color), var(--secondary-color));
    color: white;
    border-radius: var(--border-radius);
    margin-bottom: 3rem;
    animation: fadeIn 1.2s ease-out;
    box-shadow: var(--shadow);
}

.hero-section h1 {
    font-size: 3.5rem;
    margin-bottom: 1.5rem;
    font-weight: 700;
    letter-spacing: -0.5px;
}

.hero-section p {
    font-size: 1.25rem;
    max-width: 800px;
    margin: 0 auto;
    opacity: 0.95;
}

.chronometer {
    background-color: var(--card-bg);
    border-radius: var(--border-radius);
    padding: 3rem 2rem;
    box-shadow: var(--shadow);
    margin: 2rem 0;
    animation: fadeIn 1.5s ease-out;
    text-align: center;
}

.display {
    font-size: 6rem;
    font-weight: 700;
    margin: 2rem 0;
    font-family: 'Courier New', monospace;
    color: var(--primary-color);
    text-shadow: 2px 2px 4px rgba(0, 0, 0, 0.1);
    animation: pulse 2s infinite;
    letter-spacing: 2px;
}

.controls {
    display: flex;
    gap: 1rem;
    justify-content: center;
    flex-wrap: wrap;
    margin: 2rem 0;
    padding: 0 1rem;
}

.btn {
    padding: 1rem 2.5rem;
    font-size: 1.1rem;
    border: none;
    border-radius: 50px;
    cursor: pointer;
    background-color: var(--primary-color);
    color: white;
    transition: all 0.3s ease;
    box-shadow: 0 2px 10px rgba(0, 0, 0, 0.1);
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 0.5px;
}

.btn:hover {
    background-color: var(--secondary-color);
    transform: translateY(-2px);
    box-shadow: 0 4px 15px rgba(0, 0, 0, 0.2);
}

.btn:disabled {
    background-color: #ccc;
    cursor: not-allowed;
    transform: none;
    box-shadow: none;
    opacity: 0.7;
}

.laps {
    margin-top: 2rem;
    text-align: left;
    animation: slideIn 1s ease-out;
    background-color: rgba(33, 150, 243, 0.05);
    border-radius: var(--border-radius);
    padding: 2rem;
}

.laps h2 {
    font-size: 1.8rem;
    margin-bottom: 1.5rem;
    color: var(--primary-color);
    text-align: center;
}

#lapTimes {
    list-style: none;
    max-height: 300px;
    overflow-y: auto;
    padding: 1rem;
    background-color: var(--card-bg);
    border-radius: var(--border-radius);
    box-shadow: inset 0 2px 10px rgba(0, 0, 0, 0.05);
}

#lapTimes li {
    padding: 1rem;
    border-bottom: 1px solid rgba(0, 0, 0, 0.1);
    transition: background-color 0.3s ease;
    font-size: 1.1rem;
}

#lapTimes li:hover {
    background-color: rgba(33, 150, 243, 0.1);
}

.content-section {
    background: var(--card-bg);
    padding: 3rem;
    border-radius: var(--border-radius);
    margin: 2rem 0;
    box-shadow: var(--shadow);
    animation: fadeIn 1s ease-out;
}

.content-section h2 {
    color: var(--primary-color);
    font-size: 2.2rem;
    margin-bottom: 2rem;
    text-align: center;
    position: relative;
    padding-bottom: 1rem;
}

.content-section h2::after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 50%;
    transform: translateX(-50%);
    width: 100px;
    height: 3px;
    background: var(--primary-color);
    border-radius: 2px;
}

.content-section h3 {
    color: var(--secondary-color);
    font-size: 1.6rem;
    margin: 2rem 0 1rem 0;
}

.features-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: 2rem;
    margin: 2rem 0;
}

.feature-card {
    padding: 2rem;
    border-radius: var(--border-radius);
    background: rgba(33, 150, 243, 0.03);
    transition: transform 0.3s ease, box-shadow 0.3s ease;
    border: 1px solid rgba(33, 150, 243, 0.1);
}

.feature-card:hover {
    transform: translateY(-5px);
    box-shadow: var(--shadow);
}

.feature-card h3 {
    color: var(--primary-color);
    font-size: 1.4rem;
    margin-bottom: 1rem;
    text-align: center;
}

.feature-card p {
    color: var(--text-color);
    line-height: 1.6;
    text-align: center;
}

.faq-item {
    margin-bottom: 2rem;
    padding: 1.5rem;
    border-radius: var(--border-radius);
    background: rgba(33, 150, 243, 0.03);
    transition: transform 0.3s ease;
    border: 1px solid rgba(33, 150, 243, 0.1);
}

.faq-item:hover {
    transform: translateX(10px);
    background: rgba(33, 150, 243, 0.05);
}

.faq-item h3 {
    color: var(--primary-color);
    font-size: 1.3rem;
    margin-bottom: 1rem;
}

.faq-item p {
    color: var(--text-color);
    line-height: 1.8;
}

.content-section ul {
    list-style-position: inside;
    padding-left: 1.5rem;
    margin: 1rem 0;
}

.content-section ul li {
    margin-bottom: 0.8rem;
    position: relative;
    padding-left: 1rem;
}

footer {
    text-align: center;
    padding: 3rem 2rem;
    margin-top: 4rem;
    background: var(--card-bg);
    border-radius: var(--border-radius) var(--border-radius) 0 0;
    box-shadow: var(--shadow);
}

footer p {
    color: var(--text-color);
    margin: 0.5rem 0;
    font-size: 1.1rem;
}

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

    .hero-section {
        padding: 3rem 1rem;
    }

    .hero-section h1 {
        font-size: 2.5rem;
    }

    .display {
        font-size: 4rem;
    }

    .controls {
        flex-direction: column;
        padding: 0;
    }

    .btn {
        width: 100%;
    }

    .content-section {
        padding: 2rem 1.5rem;
    }

    .feature-card {
        padding: 1.5rem;
    }

    .faq-item {
        padding: 1.2rem;
    }
}