Hello! Can you improve it?
<!DOCTYPE html>
<html lang="uk">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>BehindThatTeam - Ігрові та ШІ Рішення</title>
</head>
<style>
    :root {
    --md-primary: #000000;
    --md-on-primary: #ffffff;
    --md-primary-container: #f5f5f5;
    --md-surface: #ffffff;
    --md-surface-1: #fafafa;
    --md-surface-2: #f0f0f0;
    --md-outline: #e0e0e0;
    --md-background: #ffffff;
    --md-text: #000000;
    }

    body.dark-theme {
        --md-primary: #ffffff;
        --md-on-primary: #000000;
        --md-primary-container: #1a1a1a;
        --md-surface: #121212;
        --md-surface-1: #1a1a1a;
        --md-surface-2: #242424;
        --md-outline: #333333;
        --md-background: #121212;
        --md-text: #ffffff;
    }

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

    @keyframes slideIn {
        from {
            opacity: 0;
            transform: translateX(-20px);
        }
        to {
            opacity: 1;
            transform: translateX(0);
        }
    }

    body {
        margin: 0;
        font-family: system-ui, -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Oxygen, Ubuntu, Cantarell, sans-serif;
        background-color: var(--md-background);
        color: var(--md-text);
        position: relative;
        animation: fadeIn 1s ease-in-out;
        transition: background-color 0.3s ease, color 0.3s ease;
    }

    body::before {
        content: '';
        position: fixed;
        top: 0;
        left: 0;
        width: 100%;
        height: 100%;
        background: 
            linear-gradient(to right, rgba(112, 0, 255, 0.1) 1px, transparent 1px),
            linear-gradient(to bottom, rgba(112, 0, 255, 0.1) 1px, transparent 1px);
        background-size: 40px 40px;
        z-index: -1;
        transition: background 0.3s ease;
    }

    body.dark-theme::before {
        background: 
            linear-gradient(to right, rgba(123, 31, 162, 0.15) 1px, transparent 1px),
            linear-gradient(to bottom, rgba(123, 31, 162, 0.15) 1px, transparent 1px);
        background-size: 40px 40px;
        filter: drop-shadow(0 0 5px rgba(191, 131, 255, 0.3));
        animation: gridGlow 8s ease-in-out infinite;
    }

    @keyframes gridGlow {
        0%, 100% {
            filter: drop-shadow(0 0 5px rgba(191, 131, 255, 0.3));
        }
        50% {
            filter: drop-shadow(0 0 10px rgba(191, 131, 255, 0.5));
        }
    }

    .top-app-bar {
        position: sticky;
        top: 0;
        z-index: 100;
        background: rgba(255, 255, 255, 0.9);
        backdrop-filter: blur(10px);
        border-bottom: 1px solid var(--md-outline);
        padding: 0.75rem 0;
    }

    .content {
        padding: 1rem;
        display: flex;
        flex-direction: column;
        gap: 1rem;
    }

    .button {
        border: none;
        border-radius: 4px;
        padding: 10px 24px;
        font-size: 14px;
        font-weight: 600;
        cursor: pointer;
        transition: background 0.3s ease, color 0.3s ease, transform 0.3s ease;
        text-transform: uppercase;
        letter-spacing: 0.5px;
    }

    .button.filled {
        background: var(--md-primary);
        color: var(--md-on-primary);
    }

    .button.tonal {
        background: transparent;
        color: var(--md-primary);
        border: 2px solid var(--md-primary);
    }

    .button.outlined {
        background: transparent;
        border: 1px solid var(--md-outline);
        color: var(--md-primary);
    }

    .card, .feature-card {
        background: rgba(255, 255, 255, 0.9);
        border: 1px solid var(--md-outline);
        border-radius: 12px;
        padding: 1rem;
        box-shadow: 0 4px 12px rgba(0, 0, 0, 0.1);
        color: var(--md-text);
        transition: transform 0.3s ease, box-shadow 0.3s ease, background 0.3s ease, color 0.3s ease;
        animation: fadeIn 1s ease-in-out;
    }

    .hero {
        background: transparent;
        padding: 4rem 2rem;
        text-align: center;
        position: relative;
        overflow: hidden;
    }

    .hero::before {
        content: '';
        position: absolute;
        top: 0;
        left: 0;
        width: 100%;
        height: 100%;
        background: 
            linear-gradient(45deg, var(--md-primary) 1px, transparent 1px),
            linear-gradient(-45deg, var(--md-primary) 1px, transparent 1px);
        background-size: 20px 20px;
        opacity: 0.1;
        z-index: -1;
    }

    .hero h1 {
        color: var(--md-primary);
        font-size: 2.5rem;
        margin-bottom: 1rem;
        animation: slideIn 1s ease-in-out;
    }

    .hero p {
        animation: fadeIn 1.5s ease-in-out;
    }

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

    .feature-card h3 {
        font-size: 1.5rem;
        margin-bottom: 0.5rem;
        color: var(--md-primary);
    }

    .feature-card p {
        font-size: 1rem;
        color: #333;
    }

    .feature-card:hover {
        transform: translateY(-5px);
        box-shadow: 0 8px 24px rgba(0, 0, 0, 0.2);
        background: rgba(255, 255, 255, 1); 
    }

    .feature-icon {
        font-size: 24px;
        font-weight: 900;
        color: var(--md-primary);
        display: inline-block;
        margin-bottom: 1rem;
        letter-spacing: -1px;
        transition: all 0.3s ease;
    }

    .feature-card:hover .feature-icon {
        transform: scale(1.1);
        color: var(--md-primary);
    }

    .feature-card img,
    .feature-card svg {
        display: none;
    }

    .feature-card img {
        width: 64px;
        height: 64px;
        margin-bottom: 1rem;
        transition: transform 0.3s ease, filter 0.3s ease;
    }

    .feature-card:hover img {
        transform: rotate(10deg); 
        filter: brightness(1.2);
    }

    .feature-card svg {
        width: 64px;
        height: 64px;
        margin-bottom: 1rem;
        transition: transform 0.3s ease;
    }

    .feature-card:hover svg {
        transform: rotate(10deg);
    }

    .feature-card:hover svg path,
    .feature-card:hover svg circle,
    .feature-card:hover svg rect {
        transition: all 0.3s ease;
        stroke-width: 2.5;
        stroke: #ff0000;
    }

    .nav-links {
        display: flex;
        align-items: center;
        gap: 1.5rem;
    }

    .nav-links a {
        color: var(--md-text);
        text-decoration: none;
        font-size: 0.9rem;
        font-weight: 500;
        position: relative;
        transition: color 0.3s ease;
    }

    .nav-links a::after {
        content: '';
        position: absolute;
        bottom: -4px;
        left: 0;
        width: 0;
        height: 2px;
        background: var(--md-primary);
        transition: width 0.3s ease;
    }

    .nav-links a:hover {
        color: #ff0000; 
        transform: scale(1.1);
    }

    .nav-links a:hover::after {
        width: 100%;
    }

    .button:hover {
        opacity: 1;
        background: #333;
        color: var(--md-on-primary); 
        transform: scale(1.05);
    }

    .card:hover {
        box-shadow: 0 4px 8px rgba(0, 0, 0, 0.12);
    }

    .logo-text .red {
        color: #ff0000;
        font-weight: 800;
    }

    .logo-text .green {
        color: #00ff00;
        font-weight: 800;
    }

    .logo-text .blue {
        color: #0000ff;
        font-weight: 800;
    }

    #theme-transition {
        position: fixed;
        top: 0;
        left: 0;
        width: 100%;
        height: 100%;
        pointer-events: none;
        z-index: 9999;
        display: none;
    }

    @keyframes sunset {
        0% {
            background: linear-gradient(to bottom, #ff7e00, #ff0080);
            opacity: 0;
        }
        50% {
            opacity: 0.3;
        }
        100% {
            background: linear-gradient(to bottom, #1a1a1a, #000000);
            opacity: 0;
        }
    }

    @keyframes sunrise {
        0% {
            background: linear-gradient(to top, #ff7e00, #ffff00);
            opacity: 0;
        }
        50% {
            opacity: 0.3;
        }
        100% {
            background: linear-gradient(to top, #ffffff, #87ceeb);
            opacity: 0;
        }
    }

    .theme-icon {
        margin-right: 8px;
    }

    body:not(.dark-theme) .theme-icon .moon {
        display: none;
    }

    body.dark-theme .theme-icon .sun,
    body.dark-theme .theme-icon .sun-beams {
        display: none;
    }

    #theme-toggle {
        width: 40px;
        height: 40px;
        padding: 0;
        display: flex;
        align-items: center;
        justify-content: center;
        border: 1px solid var(--md-outline);
        border-radius: 50%;
        background: transparent;
        cursor: pointer;
        transition: all 0.3s ease;
    }

    #theme-toggle:hover {
        background: var(--md-surface-2);
        transform: rotate(15deg);
    }

    #theme-toggle .theme-icon {
        width: 20px;
        height: 20px;
        margin: 0;
        color: var(--md-text); 
    }

    #theme-toggle:hover .theme-icon {
        color: var(--md-text); 
    }

    body.dark-theme #theme-toggle .theme-icon {
        color: var(--md-text);
    }

    body.dark-theme #theme-toggle:hover .theme-icon {
        color: var(--md-text);
    }

    body.dark-theme .card,
    body.dark-theme .feature-card {
        background: var(--md-surface-1);
        border-color: var(--md-outline);
    }

    body.dark-theme .feature-card p {
        color: #cccccc;
    }

    body.dark-theme .top-app-bar {
        background: rgba(18, 18, 18, 0.9);
    }

    body.dark-theme .button.outlined {
        border-color: var(--md-outline);
        color: var(--md-primary);
    }

    body.dark-theme .button:hover {
        background: var(--md-primary);
        color: var(--md-background);
    }

    body.dark-theme .feature-card:hover {
        background: var(--md-surface-2);
    }

    #theme-toggle {
        margin: 0;
        border-radius: 50%;
        aspect-ratio: 1;
        transition: background-color 0.3s ease;
    }

    #theme-toggle:hover {
        background-color: var(--md-surface-2);
        transform: rotate(15deg);
    }
</style>
<body>
    <header class="top-app-bar">
        <div style="display: flex; align-items: center; max-width: 1200px; margin: 0 auto; padding: 0 1rem;">
            <h2 class="logo-text" style="font-weight: 800; letter-spacing: -1px; margin-right: auto;">
                <span class="red">Behind</span><span class="green">That</span><span class="blue">Team</span>
            </h2>
            <div style="display: flex; align-items: center; gap: 2rem;">
                <nav class="nav-links">
                    <a href="#home">Головна</a>
                    <a href="#games">Ігри</a>
                    <a href="#ai">ШІ Рішення</a>
                    <a href="#contact">Контакти</a>
                </nav>
                <button id="theme-toggle" class="button outlined">
                    <svg class="theme-icon" width="20" height="20" viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="2">
                        <circle class="sun" cx="12" cy="12" r="4"/>
                        <path class="sun-beams" d="M12 2v2m0 16v2M4.93 4.93l1.41 1.41m11.32 11.32l1.41 1.41M2 12h2m16 0h2M4.93 19.07l1.41-1.41m11.32-11.32l1.41-1.41"/>
                        <path class="moon" d="M21 12.79A9 9 0 1 1 11.21 3 7 7 0 0 0 21 12.79z"/>
                    </svg>
                </button>
            </div>
        </div>
    </header>

    <section class="hero">
        <h1 style="font-size: 4rem; font-weight: 800; letter-spacing: -2px; margin-bottom: 2rem;">
            Ігри Зустрічають<br>Штучний Інтелект
        </h1>
        <p style="font-size: 1.2rem; color: #999; margin-bottom: 2rem;">
            Створення ігрових досвідів нового покоління, що підтримують взаємодію з штучним інтелектом.
        </p>
        <div style="display: flex; gap: 1rem; justify-content: center;">
            <button class="button filled">Наші Проекти</button>
        </div>
    </section>

    <main class="grid">
        <div class="feature-card">
            <span class="feature-icon">GAME</span>
            <h3>Розробка Ігор</h3>
            <p>Передові ігри з захоплюючими досвідами</p>
        </div>
        <div class="feature-card">
            <span class="feature-icon">AI</span>
            <h3>ШІ Рішення</h3>
            <p>Передова інтеграція ШІ в ваші застосунки</p>
        </div>
        <div class="feature-card">
            <span class="feature-icon">TECH</span>
            <h3>Інновації в Технологіях</h3>
            <p>Розширення меж інтерактивних технологій</p>
        </div>
    </main>

    <section class="content">
        <div class="card" style="max-width: 800px; margin: 0 auto;">
            <h2 style="font-weight: 700; letter-spacing: -1px;">Хто Ми Є</h2>
            <p style="color: #999; line-height: 1.6;">
                У BehindThatTeam ми захоплюємося створенням виняткових ігрових досвідів 
                та інноваційними ШІ рішенями. Наша команда розробників та ШІ спеціалістів 
                працює разом, щоб розширити межі можливого в інтерактивних розвагах.
            </p>
            <button class="button tonal">Приєднатися до Нашої Команди</button>
        </div>
    </section>

    <div id="theme-transition"></div>
    <script>
        const themeToggle = document.getElementById('theme-toggle');
        const themeTransition = document.getElementById('theme-transition');

        themeToggle.addEventListener('click', () => {
            document.body.classList.toggle('dark-theme');
            const isDark = document.body.classList.contains('dark-theme');
            themeTransition.style.display = 'block';
            themeTransition.style.animation = isDark ? 'sunset 1s forwards' : 'sunrise 1s forwards';
            
            setTimeout(() => {
                themeTransition.style.display = 'none';
            }, 1000);
        });
    </script>
</body>
</html>