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

body {
    background-color: #121212;
    color: #fff;
    line-height: 1.6;
}

.header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 1rem 2rem;
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 1000;
  background-color: rgba(0, 0, 0, 0.3);
  backdrop-filter: blur(8px);
  border: 1px solid rgba(255, 255, 255, 0.2);
}

.hero {
  margin-top: 70px;
}

.logo {
    display: flex;
    align-items: center;
}

.logo img {
    width: 40px;
    height: 40px;
    border-radius: 50%;
    margin-right: 0.5rem;
}

.logo span {
    font-size: 1.2rem;
    font-weight: bold;
}

.buy-link {
    color: #fff;
    text-decoration: none;
    opacity: 0.8;
    transition: opacity 0.3s ease;
    border: 1px solid #fff;
    padding: 0.5rem 1.2rem;
    border-radius: 50px;
}

.buy-link:hover {
    opacity: 1;
}

.hero {
    background: url('https://via.placeholder.com/1000x400') center/cover no-repeat;
    padding: 4rem 2rem;
}

.hero-content {
    max-width: 600px;
}

.hand-icon {
    font-size: 2rem;
    margin-bottom: 1rem;
    display: inline-block;
}

.hero-content h1 {
    font-size: 2.5rem;
    margin-bottom: 1rem;
    line-height: 1.2;
}

.hero-content p {
    font-size: 1.1rem;
    opacity: 0.8;
    margin-bottom: 1.2rem;
}

.gray-btn {
    display: inline-block;
    background-color: #555;
    color: #fff;
    text-decoration: none;
    padding: 0.6rem 1.2rem;
    border-radius: 4px;
    font-size: 1rem;
    transition: background-color 0.3s ease;
}

.gray-btn:hover {
    background-color: #666;
}

.product-section {
    display: flex;
    flex-direction: column;
    gap: 2rem;
    padding: 2rem 2rem;
}

.product-card {
    background-size: cover;
    background-position: center;
    padding: 2rem;
    border-radius: 8px;
    transition: transform 0.3s ease, box-shadow 0.3s ease;
    border: 1px solid rgba(255, 255, 255, 0.2);
}

.product-card:hover {
    transform: translateY(-5px);
    box-shadow: 0 0 20px rgba(255, 255, 255, 0.1);
}

.product-card h2 {
    font-size: 1.5rem;
    margin-bottom: 1rem;
}

.product-card p {
    opacity: 0.8;
    line-height: 1.6;
}

.research-section {
    padding: 3rem 2rem;
    display: flex;
    flex-direction: column;
    gap: 2rem;
}

.section-title {
    font-size: 2rem;
    margin-bottom: 1rem;
}

.research-card {
    background-color: #121212;
    padding: 1.5rem;
    border-radius: 8px;
    transition: transform 0.3s ease, box-shadow 0.3s ease;
    border: 1px solid rgba(255, 255, 255, 0.2);
    height: 100%;
}

.research-card:hover {
    transform: translateY(-5px);
    box-shadow: 0 0 20px rgba(255, 255, 255, 0.1);
}

.research-card img {
    width: 100%;
    border-radius: 4px;
    margin-bottom: 1rem;    
    display: block;
    margin: 0 auto;
}

.research-card h3 {
    font-size: 1.3rem;
    margin-bottom: 0.5rem;
}

.research-card p {
    opacity: 0.8;
    margin-bottom: 0.5rem;
}

.research-card-2 {
    background-color: #121212;
    padding: 1.5rem;
    border-radius: 8px;
    transition: transform 0.3s ease, box-shadow 0.3s ease;
    border: 1px solid rgba(255, 255, 255, 0.2);
    height: 100%;
}

.research-card-2:hover {
    transform: translateY(-5px);
    box-shadow: 0 0 20px rgba(255, 255, 255, 0.1);
}

.research-card-2 img {
    width: 70%;
    border-radius: 4px;
    margin-bottom: 1rem;    
    display: block;
    margin: 0 auto;
}

.research-card-2 h3 {
    font-size: 1.3rem;
    margin-bottom: 0.5rem;
}

.research-card-2 p {
    opacity: 0.8;
    margin-bottom: 0.5rem;
}

.research-card-3 {
    background-color: #121212;
    padding: 1.5rem;
    border-radius: 8px;
    transition: transform 0.3s ease, box-shadow 0.3s ease;
    border: 1px solid rgba(255, 255, 255, 0.2);
    height: 100%;
}
.research-card-3:hover {
    transform: translateY(-5px);
    box-shadow: 0 0 20px rgba(255, 255, 255, 0.1);
}
.research-card-3 h3 {
    font-size: 1.3rem;
    margin-top: 0;
    margin-bottom: 0.5rem;
}
.research-card-3 p {
    opacity: 0.8;
    margin-bottom: 0.5rem;
}

.research-card-link {
    text-decoration: none;
    color: inherit;
}

.footer {
  text-align: center;
  padding: 2rem;
  opacity: 0.9;
  border-top: 1px solid rgba(255, 255, 255, 0.2);
  background-color: #1a1a1a;
  margin-top: 2rem;
}

@media (min-width: 768px) {
    .product-section {
        flex-direction: row;
        flex-wrap: wrap;
        justify-content: space-between;
    }

    .product-card {
        flex: 1 1 calc(50% - 1rem);
    }

    .research-section {
        flex-direction: row;
        flex-wrap: wrap;
        justify-content: space-between;
    }

    .research-card {
        flex: 1 1 calc(50% - 1rem);
    }
}