*, *::before, *::after { box-sizing: border-box; }

body { background: #f5f7f6; color: #222; }

.container {
    max-width: 1180px;
    margin: 0 auto;
    padding: 40px 24px 64px;
}

/* ─── Breadcrumb ─── */
.breadcrumb {
    display: flex;
    align-items: center;
    gap: 6px;
    font-size: 13px;
    color: #999;
    margin-bottom: 20px;
    flex-wrap: wrap;
}
.breadcrumb a {
    color: #1d7a6f;
    text-decoration: none;
}
.breadcrumb a:hover { text-decoration: underline; }
.breadcrumb .sep { font-size: 10px; color: #ccc; }

/* ─── Main Grid ─── */
.product-detail {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 40px;
    background: #fff;
    border-radius: 24px;
    padding: 36px;
    box-shadow: 0 4px 40px rgba(0,0,0,.08);
    align-items: start;
}

/* ─── Gallery ─── */
.product-gallery { grid-column: 1; }

.main-image {
    width: 100%;
    aspect-ratio: 4/3;
    border-radius: 16px;
    overflow: hidden;
    background: #f0f4f3;
    margin-bottom: 14px;
    display: flex;
    align-items: center;
    justify-content: center;
}

.main-image img {
    width: 100%;
    height: 100%;
    object-fit: contain;
    display: block;
    transition: opacity .2s;
}

.thumb-list {
    display: flex;
    gap: 10px;
    flex-wrap: wrap;
}

.thumb {
    width: 72px;
    height: 72px;
    border-radius: 10px;
    overflow: hidden;
    border: 2px solid #e2eaea;
    cursor: pointer;
    opacity: .55;
    transition: all .2s;
    background: #f5f7f6;
    flex-shrink: 0;
}

.thumb:hover {
    opacity: .9;
    border-color: #1d7a6f;
    transform: translateY(-2px);
}

.thumb.active {
    opacity: 1;
    border-color: #1d7a6f;
    box-shadow: 0 0 0 3px rgba(29,122,111,.15);
}

.thumb img {
    width: 100%;
    height: 100%;
    object-fit: contain;
    display: block;
}

/* ─── Product Info ─── */
.product-info {
    grid-column: 2;
    display: flex;
    flex-direction: column;
}

.category {
    display: inline-block;
    background: #e8f5f2;
    color: #1d7a6f;
    padding: 5px 14px;
    border-radius: 999px;
    font-size: 13px;
    font-weight: 600;
    margin-bottom: 14px;
    width: fit-content;
}

.product-title {
    font-size: 28px;
    font-weight: 800;
    color: #1a2e2b;
    line-height: 1.3;
    margin-bottom: 20px;
}

/* ─── Price ─── */
.price-wrap {
    background: linear-gradient(135deg, #1d463f 0%, #1d7a6f 100%);
    border-radius: 14px;
    padding: 18px 22px;
    margin-bottom: 24px;
    display: flex;
    align-items: center;
    justify-content: space-between;
}

.price {
    font-size: 30px;
    font-weight: 800;
    color: #fff;
    letter-spacing: -.5px;
}

.price-note {
    font-size: 12px;
    color: rgba(255,255,255,.65);
    font-weight: 500;
}

.short-desc {
    font-size: 15px;
    line-height: 1.8;
    color: #666;
    margin-bottom: 20px;
}

/* ─── Spec Box ─── */
.spec-box {
    background: #f8fbfb;
    border: 1px solid #e3eded;
    border-radius: 16px;
    padding: 20px 22px;
    margin-bottom: 24px;
}

.spec-box h3 {
    font-size: 13px;
    text-transform: uppercase;
    letter-spacing: 1.5px;
    color: #1d7a6f;
    font-weight: 700;
    margin-bottom: 14px;
    padding-left: 10px;
    border-left: 3px solid #1d7a6f;
}

.spec-box ul {
    list-style: none;
    padding: 0;
    display: flex;
    flex-direction: column;
    gap: 0;
}

.spec-box ul li {
    display: flex;
    align-items: center;
    gap: 10px;
    font-size: 15px;
    color: #333;
    line-height: 1.5;
    padding: 9px 0;
    border-bottom: 1px solid #eef3f2;
}

.spec-box ul li:last-child { border-bottom: none; }

.spec-box ul li::before {
    content: '';
    width: 20px;
    height: 20px;
    border-radius: 50%;
    background: #e8f5f2 url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 12 12'%3E%3Cpath fill='%231d7a6f' d='M9.5 3L5 8 2.5 5.5 1.5 6.5 5 10 10.5 4z'/%3E%3C/svg%3E") center / 11px no-repeat;
    flex-shrink: 0;
}

/* ─── Action Buttons ─── */
.action-group {
    display: flex;
    flex-direction: column;
    gap: 12px;
    margin-top: auto;
    padding-top: 4px;
}

.btn {
    padding: 15px 24px;
    border: none;
    border-radius: 12px;
    font-size: 16px;
    font-weight: 600;
    cursor: pointer;
    transition: all .2s;
    width: 100%;
    letter-spacing: .3px;
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 10px;
    text-align: center;
}

.btn-buy {
    background: linear-gradient(135deg, #1d7a6f, #1d463f);
    color: white;
    box-shadow: 0 6px 20px rgba(29,122,111,.28);
}

.btn-buy:hover {
    background: linear-gradient(135deg, #1a6b61, #132e29);
    transform: translateY(-2px);
    box-shadow: 0 10px 28px rgba(29,122,111,.36);
}

.btn-back {
    background: transparent;
    color: #666;
    border: 1.5px solid #dde4e3;
}

.btn-back:hover {
    background: #f0f4f3;
    color: #1d463f;
    border-color: #bdd4d0;
}

/* ─── Detail Section (full width) ─── */
.detail-section {
    grid-column: 1 / -1;
    background: #f8fbfb;
    border: 1px solid #e8eded;
    border-radius: 20px;
    padding: 28px 32px;
}

.detail-section h2 {
    font-size: 18px;
    color: #1a2e2b;
    margin-bottom: 12px;
    font-weight: 700;
    padding-left: 12px;
    border-left: 3px solid #1d7a6f;
}

.detail-section p {
    line-height: 1.9;
    color: #555;
    font-size: 15px;
}

/* ─────────────────────────
   Responsive
───────────────────────── */

@media (max-width: 1024px) {
    .container { padding: 32px 20px 56px; }
    .product-detail { gap: 28px; padding: 28px; }
    .product-title { font-size: 24px; }
}

@media (max-width: 768px) {
    .container { padding: 20px 14px 48px; }

    .product-detail {
        grid-template-columns: 1fr;
        gap: 0;
        border-radius: 16px;
        padding: 0;
        overflow: hidden;
    }

    .product-gallery {
        grid-column: 1;
        padding: 20px 20px 16px;
        border-bottom: 1px solid #f0f4f3;
        background: #fff;
    }

    .product-info {
        grid-column: 1;
        padding: 20px;
        background: #fff;
    }

    .detail-section {
        grid-column: 1;
        margin-top: 14px;
        border-radius: 16px;
        padding: 22px 20px;
    }

    .product-title { font-size: 22px; }
    .price { font-size: 26px; }
    .thumb { width: 62px; height: 62px; }
}

@media (max-width: 480px) {
    .container { padding: 14px 10px 40px; }
    .product-gallery { padding: 16px 14px 12px; }
    .product-info { padding: 14px; }
    .product-title { font-size: 20px; }
    .price { font-size: 22px; }
    .price-wrap { padding: 14px 16px; }
    .spec-box { padding: 14px 16px; }
    .thumb { width: 52px; height: 52px; }
    .btn { padding: 13px 16px; font-size: 15px; }
    .detail-section { padding: 18px 14px; margin-top: 10px; }
}