/* ========================================
   Soto Machinery - Category Pages CSS
   Shared: Wastewater + Waste Gas Treatment
   Version: 1.0.0
   ======================================== */

:root {
    --soto-primary: #0d7377;
    --soto-secondary: #145374;
    --soto-accent: #f5a623;
    --soto-text: #2d3748;
    --soto-text-light: #5a6b7d;
    --soto-bg: #f7f9fc;
    --soto-white: #ffffff;
    --soto-border: #e8edf2;
    --soto-radius: 8px;
    --soto-shadow: 0 4px 20px rgba(0,0,0,0.08);
    --soto-shadow-hover: 0 8px 30px rgba(0,0,0,0.12);
    --soto-transition: all 0.3s ease;
    --soto-container: 1400px;
}

.soto-category-page {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', 'Noto Sans CJK SC', 'PingFang SC', 'Microsoft YaHei', sans-serif;
    color: var(--soto-text);
    line-height: 1.7;
    box-sizing: border-box;
}

.soto-category-page *, .soto-category-page *::before, .soto-category-page *::after { box-sizing: border-box; margin: 0; padding: 0; }
.soto-category-page a { text-decoration: none; color: var(--soto-primary); transition: var(--soto-transition); }
.soto-category-page a:hover { color: var(--soto-accent); }
.soto-category-page img { max-width: 100%; height: auto; display: block; }
.soto-category-page .soto-container { max-width: var(--soto-container); margin: 0 auto; padding: 0 24px; }

/* Hero */
.soto-cat-hero { position: relative; background: linear-gradient(135deg, rgba(13,115,119,0.92) 0%, rgba(20,83,116,0.95) 100%); padding: 80px 0 60px; overflow: hidden; }
.soto-cat-hero::before { content: ''; position: absolute; inset: 0; background-size: cover; background-position: center; opacity: 0.2; z-index: 0; }
.soto-cat-hero .soto-container { position: relative; z-index: 1; }
.soto-breadcrumb { display: flex; align-items: center; gap: 8px; font-size: 14px; color: rgba(255,255,255,0.7); margin-bottom: 20px; }
.soto-breadcrumb a { color: rgba(255,255,255,0.85); }
.soto-breadcrumb a:hover { color: #fff; }
.soto-breadcrumb span { color: rgba(255,255,255,0.5); }
.soto-breadcrumb .soto-current { color: #fff; font-weight: 500; }
.soto-cat-hero h1 { font-size: 46px; font-weight: 700; color: #fff; line-height: 1.2; margin-bottom: 16px; }
.soto-cat-hero p { font-size: 18px; color: rgba(255,255,255,0.85); max-width: 800px; line-height: 1.6; }

/* Overview */
.soto-cat-overview { padding: 80px 0; }
.soto-cat-overview-grid { display: grid; grid-template-columns: 1fr 1fr; gap: 48px; align-items: center; }
.soto-cat-overview-text h2 { font-size: 32px; font-weight: 700; color: var(--soto-text); margin-bottom: 20px; }
.soto-cat-overview-text p { font-size: 17px; color: var(--soto-text-light); margin-bottom: 16px; }
.soto-cat-overview-text ul { list-style: none; padding: 0; margin: 24px 0; }
.soto-cat-overview-text ul li { padding-left: 28px; position: relative; margin-bottom: 10px; font-size: 16px; color: var(--soto-text); }
.soto-cat-overview-text ul li::before { content: ''; position: absolute; left: 0; top: 8px; width: 8px; height: 8px; border-radius: 50%; background: var(--soto-primary); }
.soto-cat-overview-image { border-radius: var(--soto-radius); overflow: hidden; box-shadow: var(--soto-shadow); }
.soto-cat-overview-image img { width: 100%; height: 400px; object-fit: cover; }

/* Process Flow */
.soto-cat-process { padding: 80px 0; background: var(--soto-bg); }
.soto-section-header { text-align: center; max-width: 700px; margin: 0 auto 56px; }
.soto-section-label { display: inline-block; font-size: 13px; font-weight: 600; text-transform: uppercase; letter-spacing: 2px; color: var(--soto-primary); background: rgba(13,115,119,0.08); padding: 6px 16px; border-radius: 50px; margin-bottom: 16px; }
.soto-section-header h2 { font-size: 36px; font-weight: 700; color: var(--soto-text); line-height: 1.3; margin-bottom: 12px; }
.soto-section-header p { font-size: 17px; color: var(--soto-text-light); }
.soto-process-steps { display: grid; grid-template-columns: repeat(4, 1fr); gap: 24px; }
.soto-process-step { background: var(--soto-white); border-radius: var(--soto-radius); padding: 32px 24px; text-align: center; position: relative; }
.soto-process-step-num { width: 48px; height: 48px; background: var(--soto-primary); color: #fff; border-radius: 50%; display: flex; align-items: center; justify-content: center; font-size: 20px; font-weight: 700; margin: 0 auto 16px; }
.soto-process-step h3 { font-size: 18px; font-weight: 700; color: var(--soto-text); margin-bottom: 8px; }
.soto-process-step p { font-size: 14px; color: var(--soto-text-light); }

/* Product Grid */
.soto-cat-products { padding: 80px 0; }
.soto-product-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 32px; }
.soto-product-card { background: var(--soto-white); border: 1px solid var(--soto-border); border-radius: var(--soto-radius); overflow: hidden; transition: var(--soto-transition); }
.soto-product-card:hover { box-shadow: var(--soto-shadow-hover); transform: translateY(-4px); border-color: transparent; }
.soto-product-card-img { width: 100%; height: 220px; overflow: hidden; }
.soto-product-card-img img { width: 100%; height: 100%; object-fit: cover; transition: transform 0.3s ease; }
.soto-product-card:hover .soto-product-card-img img { transform: scale(1.05); }
.soto-product-card-body { padding: 24px; }
.soto-product-card-body h3 { font-size: 20px; font-weight: 700; color: var(--soto-text); margin-bottom: 8px; }
.soto-product-card-body p { font-size: 15px; color: var(--soto-text-light); margin-bottom: 16px; line-height: 1.6; }
.soto-product-card-tags { display: flex; flex-wrap: wrap; gap: 6px; margin-bottom: 16px; }
.soto-product-tag { font-size: 12px; padding: 3px 10px; border-radius: 50px; background: rgba(13,115,119,0.08); color: var(--soto-primary); font-weight: 500; }
.soto-product-card-link { display: inline-flex; align-items: center; gap: 6px; color: var(--soto-accent); font-weight: 600; font-size: 15px; }
.soto-product-card-link:hover { color: #e0951a; }

/* Comparison Table */
.soto-cat-compare { padding: 80px 0; background: var(--soto-bg); }
.soto-compare-table { width: 100%; border-collapse: collapse; background: var(--soto-white); border-radius: var(--soto-radius); overflow: hidden; box-shadow: var(--soto-shadow); }
.soto-compare-table th { background: var(--soto-primary); color: #fff; padding: 16px 20px; text-align: left; font-size: 15px; font-weight: 600; }
.soto-compare-table td { padding: 14px 20px; border-bottom: 1px solid var(--soto-border); font-size: 15px; color: var(--soto-text); }
.soto-compare-table tr:last-child td { border-bottom: none; }
.soto-compare-table tr:nth-child(even) td { background: var(--soto-bg); }
.soto-compare-table .soto-compare-product { font-weight: 600; color: var(--soto-primary); }

/* CTA */
.soto-cta-section { background: linear-gradient(135deg, var(--soto-primary), var(--soto-secondary)); padding: 64px 0; text-align: center; position: relative; overflow: hidden; }
.soto-cta-section::before { content: ''; position: absolute; inset: 0; background-size: cover; background-position: center; opacity: 0.15; }
.soto-cta-content { position: relative; z-index: 1; max-width: 700px; margin: 0 auto; padding: 0 24px; }
.soto-cta-content h2 { font-size: 32px; font-weight: 700; color: #fff; margin-bottom: 12px; }
.soto-cta-content p { font-size: 17px; color: rgba(255,255,255,0.85); margin-bottom: 32px; }
.soto-cta-buttons { display: flex; gap: 16px; justify-content: center; flex-wrap: wrap; }
.soto-btn { display: inline-flex; align-items: center; gap: 8px; padding: 14px 32px; border-radius: 6px; font-size: 16px; font-weight: 600; transition: var(--soto-transition); cursor: pointer; }
.soto-btn svg { width: 20px; height: 20px; fill: currentColor; }
.soto-btn-primary { background: #fff; color: var(--soto-primary); border: 2px solid #fff; }
.soto-btn-primary:hover { background: var(--soto-accent); color: #fff; border-color: var(--soto-accent); transform: translateY(-2px); box-shadow: 0 6px 20px rgba(0,0,0,0.3); }
.soto-btn-outline { background: var(--soto-accent); color: #fff; border: 2px solid var(--soto-accent); }
.soto-btn-outline:hover { background: #e0951a; border-color: #e0951a; color: #fff; transform: translateY(-2px); box-shadow: 0 6px 20px rgba(245,166,35,0.4); }
.soto-cat-form-contact-text a, .soto-cat-form-contact-text p { font-size: 17px; color: var(--soto-text); font-weight: 600; margin: 0; text-decoration: none; transition: color .2s; }
.soto-cat-form-contact-text a:hover { color: var(--soto-primary); text-decoration: underline; }

/* Industry Applications */
.soto-cat-industries { padding: 80px 0; }
.soto-cat-industries-grid { display: grid; grid-template-columns: repeat(4, 1fr); gap: 24px; }
.soto-cat-industry-card { background: var(--soto-white); border: 1px solid var(--soto-border); border-radius: var(--soto-radius); padding: 32px 24px; text-align: center; transition: var(--soto-transition); }
.soto-cat-industry-card:hover { box-shadow: var(--soto-shadow); border-color: transparent; transform: translateY(-4px); }
.soto-cat-industry-icon { width: 64px; height: 64px; background: rgba(13,115,119,0.1); border-radius: 50%; display: flex; align-items: center; justify-content: center; margin: 0 auto 16px; }
.soto-cat-industry-icon svg { width: 32px; height: 32px; fill: var(--soto-primary); }
.soto-cat-industry-card h3 { font-size: 16px; font-weight: 700; color: var(--soto-text); margin-bottom: 6px; }
.soto-cat-industry-card p { font-size: 13px; color: var(--soto-text-light); }

/* Why Choose Us */
.soto-cat-why { padding: 80px 0; background: var(--soto-bg); }
.soto-cat-why-grid { display: grid; grid-template-columns: 1fr 1fr; gap: 48px; align-items: center; }
.soto-cat-why-img { border-radius: var(--soto-radius); overflow: hidden; box-shadow: var(--soto-shadow); }
.soto-cat-why-img img { width: 100%; height: 420px; object-fit: cover; }
.soto-cat-why-text h2 { font-size: 32px; font-weight: 700; color: var(--soto-text); margin-bottom: 16px; }
.soto-cat-why-text > p { font-size: 16px; color: var(--soto-text-light); margin-bottom: 28px; }
.soto-cat-why-list { display: flex; flex-direction: column; gap: 20px; }
.soto-cat-why-item { display: flex; gap: 16px; }
.soto-cat-why-icon { width: 48px; height: 48px; background: var(--soto-white); border-radius: 50%; display: flex; align-items: center; justify-content: center; flex-shrink: 0; box-shadow: 0 2px 8px rgba(0,0,0,0.06); }
.soto-cat-why-icon svg { width: 24px; height: 24px; fill: var(--soto-primary); }
.soto-cat-why-item h4 { font-size: 17px; font-weight: 700; color: var(--soto-text); margin-bottom: 4px; }
.soto-cat-why-item p { font-size: 14px; color: var(--soto-text-light); margin: 0; }

/* Stats / Numbers */
.soto-cat-stats { padding: 64px 0; background: linear-gradient(135deg, var(--soto-primary), var(--soto-secondary)); position: relative; overflow: hidden; }
.soto-cat-stats::before { content: ''; position: absolute; inset: 0; background-size: cover; background-position: center; opacity: 0.1; }
.soto-cat-stats .soto-container { position: relative; z-index: 1; }
.soto-cat-stats-grid { display: grid; grid-template-columns: repeat(4, 1fr); gap: 32px; }
.soto-cat-stat { text-align: center; }
.soto-cat-stat-num { font-size: 48px; font-weight: 800; color: #fff; margin-bottom: 8px; line-height: 1; }
.soto-cat-stat-num span { font-size: 24px; }
.soto-cat-stat-label { font-size: 15px; color: rgba(255,255,255,0.8); font-weight: 500; }

/* FAQ Section for Category */
.soto-cat-faq { padding: 80px 0; }
.soto-cat-faq-grid { display: grid; grid-template-columns: 1fr 1.5fr; gap: 48px; align-items: start; }
.soto-cat-faq-sidebar h2 { font-size: 28px; font-weight: 700; color: var(--soto-text); margin-bottom: 12px; }
.soto-cat-faq-sidebar p { font-size: 16px; color: var(--soto-text-light); margin-bottom: 24px; }
.soto-cat-faq-cta { padding: 24px; background: var(--soto-bg); border-radius: var(--soto-radius); margin-top: 24px; }
.soto-cat-faq-cta p { font-size: 14px; color: var(--soto-text-light); margin-bottom: 12px; }
.soto-cat-faq-cta a { display: inline-flex; align-items: center; gap: 6px; font-weight: 600; color: var(--soto-primary); }
.soto-cat-faq-list { display: flex; flex-direction: column; gap: 12px; }
.soto-cat-faq-item { background: var(--soto-white); border: 1px solid var(--soto-border); border-radius: var(--soto-radius); overflow: hidden; }
.soto-cat-faq-q { padding: 18px 24px; cursor: pointer; display: flex; justify-content: space-between; align-items: center; font-size: 16px; font-weight: 600; color: var(--soto-text); }
.soto-cat-faq-q .soto-cat-faq-icon { font-size: 20px; color: var(--soto-primary); transition: transform 0.3s ease; }
.soto-cat-faq-item.active .soto-cat-faq-q .soto-cat-faq-icon { transform: rotate(45deg); }
.soto-cat-faq-a { max-height: 0; overflow: hidden; transition: max-height 0.3s ease, padding 0.3s ease; }
.soto-cat-faq-item.active .soto-cat-faq-a { max-height: 400px; padding: 0 24px 18px; }
.soto-cat-faq-a p { font-size: 15px; color: var(--soto-text-light); line-height: 1.7; }

/* FAQ — native <details>/<summary> accordion */
.soto-cat-faq-item[open] { border-color: var(--soto-primary); box-shadow: 0 4px 14px rgba(13,115,119,.08); }
.soto-cat-faq-item summary { padding: 18px 24px; cursor: pointer; font-size: 16px; font-weight: 600; color: var(--soto-text); display: flex; justify-content: space-between; align-items: center; list-style: none; transition: color .2s; }
.soto-cat-faq-item summary::-webkit-details-marker { display: none; }
.soto-cat-faq-item summary::after { content: '+'; font-size: 22px; color: var(--soto-primary); font-weight: 400; line-height: 1; }
.soto-cat-faq-item[open] summary { color: var(--soto-primary); border-bottom: 1px solid var(--soto-border); }
.soto-cat-faq-item[open] summary::after { content: '−'; }
.soto-cat-faq-answer { padding: 16px 24px 20px; font-size: 15px; color: var(--soto-text-light); line-height: 1.7; }

/* Project / Case Section */
.soto-cat-projects { padding: 80px 0; background: var(--soto-bg); }
.soto-cat-projects-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 28px; }
.soto-cat-project-card { background: var(--soto-white); border-radius: var(--soto-radius); overflow: hidden; box-shadow: var(--soto-shadow); transition: var(--soto-transition); }
.soto-cat-project-card:hover { transform: translateY(-4px); box-shadow: var(--soto-shadow-hover); }
.soto-cat-project-img { width: 100%; height: 200px; overflow: hidden; position: relative; }
.soto-cat-project-img img { width: 100%; height: 100%; object-fit: cover; }
.soto-cat-project-tag { position: absolute; top: 12px; left: 12px; background: var(--soto-accent); color: #fff; font-size: 12px; font-weight: 600; padding: 4px 10px; border-radius: 4px; }
.soto-cat-project-body { padding: 20px 24px; }
.soto-cat-project-body h3 { font-size: 17px; font-weight: 700; color: var(--soto-text); margin-bottom: 6px; }
.soto-cat-project-body p { font-size: 14px; color: var(--soto-text-light); margin-bottom: 12px; }
.soto-cat-project-meta { display: flex; gap: 16px; font-size: 12px; color: var(--soto-text-light); }
.soto-cat-project-meta span { display: flex; align-items: center; gap: 4px; }

/* Contact Form Section for Category */
.soto-cat-form { padding: 80px 0; background: var(--soto-bg); }
.soto-cat-form-grid { display: grid; grid-template-columns: 1fr 1fr; gap: 56px; align-items: start; }
.soto-cat-form-info h2 { font-size: 32px; font-weight: 700; color: var(--soto-text); margin-bottom: 16px; }
.soto-cat-form-info > p { font-size: 17px; color: var(--soto-text-light); margin-bottom: 32px; }
.soto-cat-form-contact-item { display: flex; align-items: center; gap: 16px; padding: 18px 22px; background: var(--soto-white); border-radius: var(--soto-radius); margin-bottom: 14px; border: 1px solid var(--soto-border); transition: var(--soto-transition); }
.soto-cat-form-contact-item:hover { box-shadow: 0 4px 12px rgba(0,0,0,0.06); }
.soto-cat-form-contact-icon { width: 48px; height: 48px; background: rgba(13,115,119,0.1); border-radius: 50%; display: flex; align-items: center; justify-content: center; flex-shrink: 0; }
.soto-cat-form-contact-icon svg { width: 24px; height: 24px; fill: var(--soto-primary); }
.soto-cat-form-contact-text h4 { font-size: 13px; color: var(--soto-text-light); margin-bottom: 2px; font-weight: 500; }
.soto-cat-form-contact-text p { font-size: 17px; color: var(--soto-text); font-weight: 600; margin: 0; }
.soto-cat-form-box { background: var(--soto-white); padding: 36px; border-radius: var(--soto-radius); box-shadow: var(--soto-shadow); }
.soto-cat-form-box h3 { font-size: 24px; font-weight: 700; color: var(--soto-text); margin-bottom: 8px; }
.soto-cat-form-box > p { font-size: 15px; color: var(--soto-text-light); margin-bottom: 28px; }
.soto-cat-form-shortcode { min-height: 350px; }

/* Selection Guide / How to Choose */
.soto-cat-guide { padding: 80px 0; }
.soto-cat-guide-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 28px; }
.soto-cat-guide-card { background: var(--soto-white); border: 1px solid var(--soto-border); border-radius: var(--soto-radius); padding: 32px 28px; position: relative; overflow: hidden; }
.soto-cat-guide-card::before { content: ''; position: absolute; top: 0; left: 0; right: 0; height: 4px; background: var(--soto-primary); }
.soto-cat-guide-num { font-size: 13px; font-weight: 700; color: var(--soto-accent); text-transform: uppercase; letter-spacing: 1px; margin-bottom: 12px; }
.soto-cat-guide-card h3 { font-size: 20px; font-weight: 700; color: var(--soto-text); margin-bottom: 12px; }
.soto-cat-guide-card p { font-size: 15px; color: var(--soto-text-light); margin-bottom: 16px; }
.soto-cat-guide-card ul { list-style: none; padding: 0; margin: 0; }
.soto-cat-guide-card ul li { padding: 6px 0; padding-left: 20px; position: relative; font-size: 14px; color: var(--soto-text); }
.soto-cat-guide-card ul li::before { content: '✓'; position: absolute; left: 0; color: var(--soto-primary); font-weight: 700; }

@media (max-width: 1024px) {
    .soto-cat-overview-grid { grid-template-columns: 1fr; }
    .soto-process-steps { grid-template-columns: repeat(2, 1fr); }
    .soto-product-grid { grid-template-columns: repeat(2, 1fr); }
    .soto-cat-industries-grid { grid-template-columns: repeat(2, 1fr); }
    .soto-cat-why-grid { grid-template-columns: 1fr; }
    .soto-cat-stats-grid { grid-template-columns: repeat(2, 1fr); gap: 24px; }
    .soto-cat-faq-grid { grid-template-columns: 1fr; }
    .soto-cat-projects-grid { grid-template-columns: repeat(2, 1fr); }
    .soto-cat-form-grid { grid-template-columns: 1fr; }
    .soto-cat-guide-grid { grid-template-columns: 1fr; }
}
/* Project Gallery */
.soto-cat-gallery { padding: 80px 0; background: var(--soto-bg); }
.soto-cat-gallery-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 20px; }
.soto-cat-gallery-grid img { width: 100%; height: 220px; object-fit: cover; border-radius: 10px; transition: transform 0.3s ease, box-shadow 0.3s ease; }
.soto-cat-gallery-grid img:hover { transform: scale(1.02); box-shadow: 0 4px 20px rgba(0,0,0,0.15); }

@media (max-width: 768px) {
    .soto-cat-hero h1 { font-size: 32px; }
    .soto-process-steps { grid-template-columns: 1fr; }
    .soto-product-grid { grid-template-columns: 1fr; }
    .soto-cat-gallery-grid { grid-template-columns: repeat(2, 1fr); }
    .soto-cta-buttons { flex-direction: column; align-items: center; }
    .soto-btn { width: 100%; max-width: 300px; justify-content: center; }
    .soto-section-header h2 { font-size: 28px; }
    .soto-compare-table { font-size: 13px; }
    .soto-compare-table th, .soto-compare-table td { padding: 10px 12px; }
    .soto-cat-industries-grid { grid-template-columns: 1fr 1fr; }
    .soto-cat-stats-grid { grid-template-columns: 1fr 1fr; }
    .soto-cat-stat-num { font-size: 36px; }
    .soto-cat-projects-grid { grid-template-columns: 1fr; }
    .soto-cat-form-box { padding: 24px; }
}
@media (max-width: 480px) {
    .soto-cat-hero { padding: 60px 0 40px; }
    .soto-cat-hero h1 { font-size: 28px; }
    .soto-cat-overview, .soto-cat-process, .soto-cat-products, .soto-cat-compare { padding: 48px 0; }
    .soto-cat-industries, .soto-cat-why, .soto-cat-faq, .soto-cat-projects, .soto-cat-form, .soto-cat-guide, .soto-cat-gallery { padding: 48px 0; }
    .soto-cat-industries-grid { grid-template-columns: 1fr; }
    .soto-cat-gallery-grid { grid-template-columns: 1fr; }
    .soto-cat-stats-grid { grid-template-columns: 1fr 1fr; }
}