/* ===============================
   THEME COLORS
================================ */
:root {
    --primary-blue: #0A66C2;
    --accent-green: #00A878;
    --white: #FFFFFF;
    --light-bg: #F5F9FC;
    --dark-text: #1F2933;
}

/* ===============================
   RESET
================================ */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
}

body {
    background: var(--light-bg);
    color: var(--dark-text);
    line-height: 1.6;
}

/* ===============================
   HEADER
================================ */
header {
    background: linear-gradient(135deg, var(--primary-blue), var(--accent-green));
    color: var(--white);
    padding: 20px 0;
    text-align: center;
}

header h1 {
    font-size: 2rem;
    margin-bottom: 10px;
}

header nav a {
    color: var(--white);
    text-decoration: none;
    margin: 0 10px;
    font-weight: 600;
    transition: 0.3s;
}

header nav a:hover {
    text-decoration: underline;
}

/* ===============================
   PRODUCT DETAILS
================================ */
.product-details {
    max-width: 1000px;
    margin: 30px auto;
    background: var(--white);
    padding: 30px;
    border-radius: 12px;
    box-shadow: 0 8px 20px rgba(0,0,0,0.1);
}

.product-details h2 {
    font-size: 1.8rem;
    color: var(--primary-blue);
    margin-bottom: 20px;
    text-align: center;
}

.product-images {
    display: flex;
    flex-direction: column;
    align-items: center;
    margin-bottom: 20px;
}

.main-image {
    width: 100%;
    max-width: 400px;
    border-radius: 12px;
    margin-bottom: 15px;
}

.thumbnail-images {
    display: flex;
    gap: 10px;
}

.thumbnail-images img {
    width: 70px;
    border-radius: 8px;
    cursor: pointer;
    border: 2px solid transparent;
    transition: 0.3s;
}

.thumbnail-images img:hover {
    border-color: var(--primary-blue);
}

/* ===============================
   PRODUCT DESCRIPTION
================================ */
#product-description {
    margin-bottom: 15px;
    font-size: 1rem;
    text-align: center;
}

.product-details ul {
    list-style: none;
    padding-left: 0;
    margin-bottom: 15px;
}

.product-details ul li {
    padding: 6px 0;
    font-size: 0.95rem;
    border-bottom: 1px solid #eee;
}

/* ===============================
   PRODUCT PRICE
================================ */
#product-price {
    font-size: 1.5rem;
    font-weight: 700;
    color: var(--accent-green);
    margin: 15px 0;
    text-align: center;
}

/* ===============================
   ADD TO CART BUTTON
================================ */
#buyNowBtn {
    display: block;
    width: 60%;
    max-width: 250px;
    margin: 20px auto;
    background: var(--primary-blue);
    color: var(--white);
    border: none;
    padding: 12px 0;
    font-size: 1rem;
    font-weight: 600;
    border-radius: 8px;
    cursor: pointer;
    transition: 0.3s;
    text-align: center;
}

#buyNowBtn:hover {
    background: var(--accent-green);
}

/* ===============================
   FOOTER
================================ */
footer {
    text-align: center;
    padding: 20px;
    margin-top: 40px;
    color: var(--white);
    background: var(--primary-blue);
    border-top-left-radius: 12px;
    border-top-right-radius: 12px;
}

/* ===============================
   RESPONSIVE
================================ */
@media (max-width: 768px) {
    .product-details {
        padding: 20px;
    }

    .main-image {
        max-width: 300px;
    }

    .thumbnail-images img {
        width: 50px;
    }

    #buyNowBtn {
        width: 80%;
    }
}

@media (max-width: 480px) {
    .main-image {
        max-width: 250px;
    }

    .thumbnail-images {
        gap: 5px;
    }

    #buyNowBtn {
        width: 90%;
    }
}