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

html {
    font-size: 16px;
}

@media (min-width: 1280px) {
    html {
        font-size: 22px;
    }
}

@media (max-width: 600px) {
    html {
        font-size: 14px;
    }

    h1 {
        font-size: 2.5rem;
    }

    .p {
        font-size: 1rem;
    }

    .btn {
        padding: 1rem;
    }

    footer {
        gap: 1rem;
        flex-direction: column;
        padding-bottom: 2rem;
    }
}

body {
    background-color: #070707;
    color: #FDFDFD;
    font-family: 'Inter', sans-serif;
    min-height: 100vh;
    display: flex;
    flex-direction: column;
}

main {
    flex-grow: 1;
    display: flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;
    text-align: center;
    padding: 1.25rem;
}

h1 {
    font-weight: 800;
    font-size: 3rem;
    letter-spacing: -0.02em;
    margin-bottom: 1.25rem;
    line-height: 1.1;
}

.p {
    font-weight: 400;
    font-size: 1.1rem;
    line-height: 1.6;
    color: #E9E9E9;
    max-width: 31.25rem;
    margin-bottom: 0.625rem;
}

.p-second {
    opacity: 0.8;
}

.mb {
    margin-bottom: 1.75rem;
}

.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    background-color: #3F50B4;
    color: #E9E9E9;
    font-weight: 600;
    font-size: 1rem;
    padding: 0.9em 2em;
    border-radius: 0.75rem;
    text-decoration: none;
    transition: transform 0.2s ease, background-color 0.2s ease;
    box-shadow: 0 0.25rem 0.9rem rgba(63, 80, 180, 0.4);
}

.btn:hover {
    background-color: #324090;
    transform: translateY(-0.125rem);
}

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

a {
    color: #9CA3AF;
    text-decoration: none;
    font-size: 0.9rem;
    transition: color 0.2s ease;
}

.platforms {
    display: flex;
    gap: 1.875rem;
    justify-content: center;
    align-items: center;
    flex-wrap: wrap;
    opacity: 0.6;
}

.platform-icon {
    width: 1.875rem;
    height: 1.875rem;
    fill: #9CA3AF;
    transition: fill 0.3s ease, transform 0.2s ease;
}

.platform-icon:hover {
    fill: #FDFDFD;
    transform: scale(1.1);
}

footer {
    padding: 1.5rem;
    text-align: center;
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 1.5rem;
    margin-top: auto;
}

.footer-nav {
    display: flex;
    justify-content: center;
    gap: 1.5rem;
    flex-wrap: wrap;
}

.footer-nav a {
    color: #9CA3AF;
    text-decoration: none;
    font-size: 0.9rem;
    transition: color 0.2s ease;
}

.footer-nav a:hover {
    color: #3F50B4;
}

.copyright {
    font-size: 0.8rem;
    color: #4B5563;
}

.copyright a {
    color: #6B7280;
    text-decoration: none;
    font-weight: 600;
    transition: color 0.2s ease;
}

.copyright a:hover {
    color: #FDFDFD;
}
@media (max-width: 600px) {
    footer {
        padding-bottom: 2rem;
        gap: 2rem;
    }
    
    .footer-nav {
        flex-direction: column;
        gap: 1rem;
    }
}

details {
    width: 100%;
    max-width: 50rem;
}

summary {
    cursor: pointer;
    list-style: none;
    font-weight: 500;
    color: #9CA3AF;
    transition: color 0.2s ease;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 0.5rem;
    padding: 0.5rem 1rem;
    border: 1px solid rgba(255, 255, 255, 0.2);
    border-radius: 2rem;
}

summary::-webkit-details-marker {
    display: none;
}

summary:hover {
    color: #FDFDFD;
    border-color: #3F50B4;
}

details[open] summary::after {
    transform: rotate(45deg);
}

details[open] summary {
    margin-bottom: 1.5rem;
    color: #FDFDFD;
}

.content-width {
    width: 100%;
    max-width: 50rem;
}

a.card-link {
    text-decoration: none;
    display: block;
    height: 100%;
    cursor: pointer;
}
a.card-link:hover h4 {
    color: #3F50B4;
}

.features-grid {
    display: grid;
    grid-template-columns: repeat(2, 1fr); 
    gap: 1rem;
    width: 100%;
    max-width: 50rem;
    text-align: left;
    animation: fadeIn 0.3s ease-in-out;
}

.feature-card {
    background-color: #121212;
    border: 1px solid #1F1F1F;
    border-radius: 1rem;
    padding: 1.25rem;
    transition: transform 0.2s ease, border-color 0.2s ease;
}

.feature-card:hover {
    border-color: #3F50B4;
    transform: translateY(-2px);
}

.feature-card h4 {
    color: #FDFDFD;
    font-weight: 600;
    font-size: 1rem;
    margin-bottom: 0.5rem;
}

.feature-card p {
    color: #9CA3AF;
    font-size: 0.85rem;
    line-height: 1.4;
    margin: 0;
}

@keyframes fadeIn {
    from { opacity: 0; transform: translateY(-10px); }
    to { opacity: 1; transform: translateY(0); }
}

@media (max-width: 600px) {
    .features-grid {
        grid-template-columns: 1fr;
    }
}