img {
    max-width: 250px;
    display: block;
    margin: 1rem auto;
}

body {
    margin: 2rem;
    position: relative;
    overflow-x: hidden;
    color: #222;
}

p {
    text-align: left;
    max-width: 60ch;
}

.sr-only {
    position: absolute;
    width: 1px;
    height: 1px;
    padding: 0;
    margin: -1px;
    overflow: hidden;
    clip: rect(0, 0, 0, 0);
    white-space: nowrap;
    border: 0;
}

.math-bg {
    position: fixed;
    top: 0;
    left: 0;
    width: 100vw;
    height: 100vh;
    min-height: 100vh;
    z-index: 0;
    overflow: hidden;
    pointer-events: none;
}

.product-container {
    position: relative;
    z-index: 1;
    max-width: 600px;
    margin: 2rem auto;
    background: #fff;
    border-radius: 16px;
    box-shadow: 0 4px 24px rgba(0, 0, 0, 0.08), 0 1.5px 6px rgba(0, 0, 0, 0.04);
    padding: 2.5rem 2.5rem 2rem 2.5rem;
    text-align: center;
}

.product-title {
    font-size: 2.2rem;
    font-weight: 700;
    margin-bottom: 0.2em;
}

.product-subtitle {
    font-size: 1.2rem;
    font-weight: 400;
    color: #2d6a4f;
    margin-top: 0;
    margin-bottom: 1.2em;
}

.product-image {
    box-shadow: 0 2px 12px rgba(44, 62, 80, 0.08);
    margin-bottom: 1.2em;
}

.product-tagline {
    font-size: 1.05rem;
    color: #555;
    margin-bottom: 1.5em;
}

.product-details h3 {
    font-size: 1.1rem;
    color: #264653;
    margin-bottom: 0.5em;
    margin-top: 0;
}

.product-features {
    text-align: left;
    margin: 0 auto 1.5em auto;
    padding-left: 0;
    max-width: 600px;
    list-style: none;
}

.product-features li {
    display: flex;
    align-items: flex-start;
    margin-bottom: 0.7em;
    font-size: 1rem;
    line-height: 1.5;
}

.feature-emoji {
    display: inline-block;
    width: 2em;
    min-width: 2em;
    text-align: center;
    font-size: 1.2em;
    margin-right: 0.5em;
    flex-shrink: 0;
}

.feature-text {
    display: inline-block;
    flex: 1 1 0;
}

.product-buy {
    margin-top: 2rem;
    margin-bottom: 3rem;
}

.product-buy a {
    display: inline-block;
    background: linear-gradient(90deg, #3a2476 0%, #5f3dc4 100%);
    color: #fff;
    font-weight: 700;
    text-decoration: none;
    padding: 0.85em 2.2em;
    border-radius: 8px;
    font-size: 1.1rem;
    box-shadow: 0 2px 8px rgba(63, 36, 118, 0.13);
    transition: background 0.18s, box-shadow 0.18s, transform 0.13s;
    border: none;
    outline: none;
}

.product-buy a:hover {
    background: linear-gradient(90deg, #2a1851 0%, #3a2476 100%);
    box-shadow: 0 4px 16px rgba(63, 36, 118, 0.18);
    transform: translateY(-2px) scale(1.03);
}

.back-link {
    display: inline-block;
    color: #5f3dc4;
    font-weight: 600;
    font-size: 1.05rem;
    text-decoration: none;
    background: rgba(255, 255, 255, 0.7);
    border-radius: 6px;
    padding: 0.4em 1em 0.4em 0.7em;
    box-shadow: 0 1px 4px rgba(90, 61, 196, 0.06);
    transition: background 0.15s, color 0.15s, box-shadow 0.15s;
    position: relative;
    z-index: 2;
}

.back-link:hover {
    background: #ede9fa;
    color: #3a2476;
    text-decoration: underline;
    box-shadow: 0 2px 8px rgba(90, 61, 196, 0.10);
}

@media (max-width: 600px) {
    .product-container {
        padding: 1.2rem 0.5rem 1.5rem 0.5rem;
        max-width: 100%;
    }

    .product-features {
        max-width: 100%;
        padding-left: 0;
    }

    .product-title {
        font-size: 1.5rem;
    }

    .product-subtitle {
        font-size: 1rem;
    }
}

@media (min-width: 900px) {
    .product-container {
        display: flex;
        flex-direction: row;
        align-items: flex-start;
        max-width: 1000px;
        padding: 2.5rem 2.5rem;
        text-align: left;
        gap: 2.5rem;
    }

    .product-image,
    .product-buy {
        margin-left: 0;
        margin-right: 0;
        text-align: center;
    }

    .product-left {
        display: flex;
        flex-direction: column;
        align-items: center;
        flex: 0 0 320px;
        max-width: 320px;
        width: 100%;
        gap: 1.2em;
    }

    .product-content {
        flex: 1 1 0;
        display: flex;
        flex-direction: column;
        justify-content: center;
    }

    .product-details,
    .product-title,
    .product-subtitle,
    .product-tagline {
        text-align: left;
    }
}