/* ============================================
   COMMON.CSS - Global Shared Styles
   Hebei Cangtie Industrial Co., Ltd.
============================================ */

/* --- Google Fonts Import --- */
@import url("https://fonts.googleapis.com/css2?family=Inter:wght@300;400;500;600;700;800;900&family=Barlow+Condensed:wght@400;500;600;700;800;900&display=swap");

/* --- CSS Variables / Design Tokens --- */
:root {
  /* Primary Brand Colors - Industrial Blue */
  --clr-primary: #0a4b8f;
  --clr-primary-dark: #062d59;
  --clr-primary-mid: #0e5eaf;
  --clr-primary-light: #1a7fd4;
  --clr-accent: #f0a500;
  --clr-accent-hover: #e09500;

  /* Neutrals */
  --clr-bg: #f4f6fa;
  --clr-bg-dark: #0a0e1a;
  --clr-bg-section: #eef1f7;
  --clr-surface: #ffffff;
  --clr-border: #d8e0ee;

  /* Text Colors */
  --clr-text-primary: #0f1b2d;
  --clr-text-secondary: #4a5e78;
  --clr-text-muted: #7c93b0;
  --clr-text-white: #ffffff;
  --clr-text-light: #c8d8ea;

  /* Typography */
  --font-body: "Inter", sans-serif;
  --font-heading: "Barlow Condensed", sans-serif;

  /* Sizing */
  --max-width: 1600px;
  --page-padding: 2vw;

  /* Spacing Scale */
  --sp-xs: 4px;
  --sp-sm: 8px;
  --sp-md: 16px;
  --sp-lg: 24px;
  --sp-xl: 40px;
  --sp-2xl: 64px;
  --sp-3xl: 50px;

  /* Radius */
  --radius-sm: 4px;
  --radius-md: 8px;
  --radius-lg: 16px;
  --radius-xl: 24px;
  --radius-full: 9999px;

  /* Shadows */
  --shadow-sm: 0 2px 8px rgba(10, 75, 143, 0.08);
  --shadow-md: 0 8px 32px rgba(10, 75, 143, 0.12);
  --shadow-lg: 0 16px 64px rgba(10, 75, 143, 0.18);
  --shadow-xl: 0 32px 80px rgba(10, 75, 143, 0.22);

  /* Transitions */
  --transition-fast: 0.2s ease;
  --transition-base: 0.35s ease;
  --transition-slow: 0.6s ease;

  /* Z-index layers */
  --z-base: 1;
  --z-dropdown: 100;
  --z-sticky: 200;
  --z-overlay: 300;
  --z-modal: 400;
  --z-toast: 500;
}

/* --- CSS Reset & Base --- */
*,
*::before,
*::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

html {
  scroll-behavior: smooth;
  font-size: 16px;
  -webkit-text-size-adjust: 100%;
}

body {
  font-family: var(--font-body);
  color: var(--clr-text-primary);
  /* background-color: var(--clr-bg); */
  line-height: 1.6;
  overflow-x: hidden;
}

video {
  max-width: 100%;
  height: auto;
  display: block;
}
img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  display: block;
}
a {
  text-decoration: none;
  color: inherit;
  transition: color var(--transition-fast);
}

ul,
ol {
  list-style: none;
}

button {
  cursor: pointer;
  border: none;
  background: none;
  font-family: inherit;
}

/* --- Layout Utilities --- */
.container {
  width: 100%;
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0 var(--page-padding);
}

.section {
  padding: var(--sp-3xl) 0;
}

.section-sm {
  padding: var(--sp-2xl) 0;
}

/* --- Section Header --- */
.section-header {
  text-align: center;
  margin-bottom: var(--sp-2xl);
}

.section-label {
  display: inline-flex;
  align-items: center;
  gap: var(--sp-sm);
  font-family: var(--font-body);
  font-size: 0.75rem;
  font-weight: 700;
  letter-spacing: 0.15em;
  text-transform: uppercase;
  color: var(--clr-accent);
  margin-bottom: var(--sp-md);
}

.section-label::before,
.section-label::after {
  content: "";
  display: block;
  width: 24px;
  height: 2px;
  background: var(--clr-primary-light);
}

.section-title {
  font-family: var(--font-heading);
  font-size: clamp(2rem, 4vw, 3.25rem);
  font-weight: 800;
  line-height: 1.1;
  color: var(--clr-text-primary);
  letter-spacing: -0.01em;
}

.section-title span {
  color: var(--clr-primary-light);
}

.section-desc {
  margin-top: var(--sp-md);
  font-size: 1.05rem;
  color: var(--clr-text-secondary);
  max-width: 680px;
  margin-left: auto;
  margin-right: auto;
  line-height: 1.7;
}

/* --- Buttons --- */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: var(--sp-sm);
  padding: 14px 32px;
  border-radius: var(--radius-sm);
  font-size: 0.9rem;
  font-weight: 700;
  letter-spacing: 0.04em;
  text-transform: uppercase;
  transition: all var(--transition-base);
  cursor: pointer;
  white-space: nowrap;
  font-family: var(--font-body);
  position: relative;
  overflow: hidden;
}

.btn::after {
  content: "";
  position: absolute;
  inset: 0;
  background: rgba(255, 255, 255, 0);
  transition: background var(--transition-fast);
}

.btn:hover::after {
  background: rgba(255, 255, 255, 0.08);
}

.btn-primary {
  background: linear-gradient(
    135deg,
    var(--clr-primary-light),
    var(--clr-primary)
  );
  color: #fff;
  box-shadow: 0 4px 24px rgba(10, 75, 143, 0.35);
}

.btn-primary:hover {
  transform: translateY(-2px);
  box-shadow: 0 8px 32px rgba(10, 75, 143, 0.45);
}

.btn-accent {
  background: linear-gradient(135deg, #f0a500, #d48800);
  color: #fff;
  box-shadow: 0 4px 20px rgba(240, 165, 0, 0.35);
}

.btn-accent:hover {
  transform: translateY(-2px);
  box-shadow: 0 8px 28px rgba(240, 165, 0, 0.45);
}

.btn-outline {
  border: 2px solid var(--clr-border);
  color: var(--clr-text-primary);
  background: transparent;
}

.btn-outline:hover {
  border-color: var(--clr-primary-light);
  color: var(--clr-primary-light);
  transform: translateY(-2px);
}

.btn-outline-white {
  border: 2px solid rgba(255, 255, 255, 0.5);
  color: #fff;
  background: transparent;
}

.btn-outline-white:hover {
  border-color: #fff;
  background: rgba(255, 255, 255, 0.1);
  transform: translateY(-2px);
}

.btn-sm {
  padding: 10px 22px;
  font-size: 0.82rem;
}

.btn-lg {
  padding: 18px 44px;
  font-size: 1rem;
}

/* --- Tag / Badge --- */
.tag {
  display: inline-block;
  padding: 4px 12px;
  border-radius: var(--radius-full);
  font-size: 0.72rem;
  font-weight: 700;
  letter-spacing: 0.08em;
  text-transform: uppercase;
}

.tag-primary {
  background: rgba(10, 75, 143, 0.1);
  color: var(--clr-primary-light);
}

.tag-accent {
  background: rgba(240, 165, 0, 0.12);
  color: #d48800;
}

/* --- CTA Modal Overlay --- */
.modal-overlay {
  position: fixed;
  inset: 0;
  background: rgba(0, 0, 0, 0.65);
  backdrop-filter: blur(6px);
  -webkit-backdrop-filter: blur(6px);
  z-index: var(--z-modal);
  display: flex;
  align-items: center;
  justify-content: center;
  padding: var(--sp-md);
  opacity: 0;
  visibility: hidden;
  transition:
    opacity var(--transition-base),
    visibility var(--transition-base);
}

.modal-overlay.active {
  opacity: 1;
  visibility: visible;
}

.modal-box {
  background: var(--clr-surface);
  border-radius: var(--radius-xl);
  width: 100%;
  max-width: 640px;
  max-height: 90vh;
  overflow-y: auto;
  padding: var(--sp-xl);
  position: relative;
  transform: translateY(30px) scale(0.97);
  transition: transform var(--transition-base);
  box-shadow: var(--shadow-xl);
}

.modal-overlay.active .modal-box {
  transform: translateY(0) scale(1);
}

.modal-close {
  position: absolute;
  top: var(--sp-md);
  right: var(--sp-md);
  width: 36px;
  height: 36px;
  border-radius: var(--radius-full);
  background: var(--clr-bg-section);
  border: none;
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--clr-text-secondary);
  transition: all var(--transition-fast);
  font-size: 1rem;
}

.modal-close:hover {
  background: var(--clr-primary);
  color: #fff;
  transform: rotate(90deg);
}

.modal-title {
  font-family: var(--font-heading);
  font-size: 2rem;
  font-weight: 800;
  color: var(--clr-text-primary);
  margin-bottom: var(--sp-xs);
}

.modal-subtitle {
  font-size: 0.95rem;
  color: var(--clr-text-secondary);
  margin-bottom: var(--sp-xl);
}

/* --- Form Styles --- */
.form-group {
  margin-bottom: var(--sp-md);
}

.form-row {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: var(--sp-md);
}

.form-label {
  display: block;
  font-size: 0.85rem;
  font-weight: 600;
  color: var(--clr-text-primary);
  margin-bottom: 6px;
}

.form-control {
  width: 100%;
  padding: 12px 16px;
  border: 1.5px solid var(--clr-border);
  border-radius: var(--radius-md);
  font-family: var(--font-body);
  font-size: 0.95rem;
  color: var(--clr-text-primary);
  background: var(--clr-bg);
  transition:
    border-color var(--transition-fast),
    box-shadow var(--transition-fast);
  outline: none;
}

.form-control:focus {
  border-color: var(--clr-primary-light);
  box-shadow: 0 0 0 3px rgba(26, 127, 212, 0.15);
  background: #fff;
}

.form-control::placeholder {
  color: var(--clr-text-muted);
}

textarea.form-control {
  resize: vertical;
  min-height: 110px;
}

select.form-control {
  cursor: pointer;
  appearance: none;
  -webkit-appearance: none;
  background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='12' height='8' viewBox='0 0 12 8'%3E%3Cpath d='M1 1l5 5 5-5' stroke='%234a5e78' stroke-width='1.5' fill='none' stroke-linecap='round'/%3E%3C/svg%3E");
  background-repeat: no-repeat;
  background-position: right 14px center;
  padding-right: 40px;
}

/* --- Keyframe Animations --- */
@keyframes fadeInUp {
  from {
    opacity: 0;
    transform: translateY(30px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

@keyframes fadeIn {
  from {
    opacity: 0;
  }
  to {
    opacity: 1;
  }
}

@keyframes slideInDown {
  from {
    opacity: 0;
    transform: translateY(-20px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

@keyframes scaleIn {
  from {
    opacity: 0;
    transform: scale(0.9);
  }
  to {
    opacity: 1;
    transform: scale(1);
  }
}

@keyframes pulse-ring {
  0% {
    transform: scale(1);
    opacity: 0.6;
  }
  100% {
    transform: scale(1.5);
    opacity: 0;
  }
}

@keyframes shimmer {
  0% {
    background-position: -200% 0;
  }
  100% {
    background-position: 200% 0;
  }
}

/* --- Scroll Reveal --- */
.reveal {
  opacity: 0;
  transform: translateY(40px);
  transition:
    opacity 0.7s ease,
    transform 0.7s ease;
}

.reveal.visible {
  opacity: 1;
  transform: translateY(0);
}

.reveal-delay-1 {
  transition-delay: 0.1s;
}
.reveal-delay-2 {
  transition-delay: 0.2s;
}
.reveal-delay-3 {
  transition-delay: 0.3s;
}
.reveal-delay-4 {
  transition-delay: 0.4s;
}
.reveal-delay-5 {
  transition-delay: 0.5s;
}

/* --- Utility Classes --- */
.text-center {
  text-align: center;
}
.text-left {
  text-align: left;
}
.text-right {
  text-align: right;
}

.mt-auto {
  margin-top: auto;
}
.d-flex {
  display: flex;
}
.d-grid {
  display: grid;
}
.gap-md {
  gap: var(--sp-md);
}

/* --- Sticky Sidebar Components --- */
.sticky-sidebar {
  position: sticky;
  top: 100px;
  height: fit-content;
  display: flex;
  flex-direction: column;
  gap: var(--sp-xl);
}

.sidebar-widget {
  background: var(--clr-surface);
  border-radius: var(--radius-lg);
  padding: var(--sp-lg);
  border: 1px solid var(--clr-border);
  box-shadow: var(--shadow-sm);
}

.sidebar-title {
  font-family: var(--font-heading);
  font-size: 1.25rem;
  font-weight: 800;
  color: var(--clr-primary-dark);
  margin-bottom: var(--sp-md);
  padding-bottom: 12px;
  border-bottom: 2px solid var(--clr-primary-light);
  display: inline-block;
}

.nav-category-list {
  display: flex;
  flex-direction: column;
  gap: 6px;
}

.nav-category-group {
  display: flex;
  flex-direction: column;
}

.nav-category-row {
  display: flex;
  align-items: center;
  gap: 4px;
}

.nav-category-row .nav-category-item {
  flex: 1;
}

.nav-category-item {
  display: flex;
  gap: 15px;
  align-items: center;
  padding: 12px 16px;
  border-radius: var(--radius-md);
  color: var(--clr-text-secondary);
  text-decoration: none;
  font-weight: 500;
  font-size: 0.9rem;
  transition: all var(--transition-fast);
}

.nav-category-item:hover,
.nav-category-item.active {
  background: rgba(10, 75, 143, 0.05);
  color: var(--clr-primary);
}
.nav-category-item .nav-category-title{
  line-height: 2;
}
.nav-category-item .count {
  font-size: 0.75rem;
  color: var(--clr-text-muted);
  background: var(--clr-bg);
  padding: 2px 8px;
  border-radius: var(--radius-full);
}
.nav-category-item .nav-category-title .count{
  margin-left: 15px;
}
.nav-category-item.active .count {
  background: var(--clr-primary);
  color: #fff;
}

/* Subcategory Toggle Button */
.subcategory-toggle {
  display: flex;
  align-items: center;
  justify-content: center;
  width: 42px;
  height: 42px;
  border-radius: var(--radius-md);
  color: var(--clr-text-muted);
  background: transparent;
  border: none;
  cursor: pointer;
  transition: all var(--transition-fast);
}

.subcategory-toggle:hover {
  background: rgba(10, 75, 143, 0.08);
  color: var(--clr-primary);
}

.subcategory-toggle i {
  font-size: 0.75rem;
  transition: transform var(--transition-base);
}

.nav-category-group.open .subcategory-toggle i {
  transform: rotate(180deg);
  color: var(--clr-primary);
}

/* Subcategory List with branch styling */
.subcategory-list {
  list-style: none;
  padding: 0;
  margin: 0;
  padding-left: 20px;
  margin-left: 26px;
  border-left: 1.5px solid rgba(10, 75, 143, 0.08);
  max-height: 0;
  overflow: hidden;
  opacity: 0;
  transition: max-height 0.4s cubic-bezier(0.4, 0, 0.2, 1), opacity 0.35s ease, margin 0.35s ease;
}

.subcategory-list.open {
  max-height: 800px;
  opacity: 1;
  margin-top: 4px;
  margin-bottom: 8px;
}

.subcategory-item {
  margin-bottom: 4px;
}

.subcategory-item:last-child {
  margin-bottom: 0;
}

.subcategory-link {
  display: flex;
  align-items: center;
  padding: 8px 12px;
  border-radius: var(--radius-sm);
  color: var(--clr-text-secondary);
  font-size: 0.88rem;
  font-weight: 500;
  transition: all var(--transition-fast);
  position: relative;
  text-decoration: none;
}

.subcategory-link::before {
  content: "";
  position: absolute;
  left: -20px;
  top: 50%;
  width: 12px;
  height: 1.5px;
  background: rgba(10, 75, 143, 0.08);
  transition: all var(--transition-fast);
}

.subcategory-link:hover::before,
.subcategory-link.active::before {
  background: var(--clr-primary-light);
  width: 16px;
}

.subcategory-link:hover {
  background: rgba(10, 75, 143, 0.03);
  color: var(--clr-primary-light);
  padding-left: 16px;
}

.subcategory-link.active {
  background: rgba(10, 75, 143, 0.06);
  color: var(--clr-primary);
  font-weight: 600;
  padding-left: 16px;
}

.subcategory-dot {
  width: 6px;
  height: 6px;
  border-radius: 50%;
  background: var(--clr-text-muted);
  margin-right: 8px;
  transition: all var(--transition-fast);
  flex-shrink: 0;
}

.subcategory-link:hover .subcategory-dot,
.subcategory-link.active .subcategory-dot {
  background: var(--clr-accent);
  box-shadow: 0 0 6px var(--clr-accent);
}

.subcategory-name {
  flex: 1;
}

.subcategory-count {
  font-size: 0.72rem;
  color: var(--clr-text-muted);
  background: var(--clr-bg);
  padding: 1px 6px;
  border-radius: var(--radius-full);
  margin-left: 8px;
  transition: all var(--transition-fast);
}

.subcategory-link.active .subcategory-count {
  background: var(--clr-primary-light);
  color: #fff;
}

.sidebar-contact-box {
  background: linear-gradient(
    135deg,
    var(--clr-primary-dark),
    var(--clr-primary)
  );
  color: #fff;
  border-radius: var(--radius-lg);
  padding: var(--sp-lg);
  text-align: center;
}

.sidebar-contact-box h4 {
  font-family: var(--font-heading);
  font-size: 1.5rem;
  margin-bottom: 8px;
}

.sidebar-contact-box p {
  font-size: 0.85rem;
  opacity: 0.8;
  margin-bottom: 20px;
}

@media (max-width: 1024px) {
  .sticky-sidebar {
    position: relative;
    top: 0;
    margin-bottom: var(--sp-2xl);
  }
}

.visually-hidden {
  position: absolute;
  width: 1px;
  height: 1px;
  overflow: hidden;
  clip: rect(0, 0, 0, 0);
  white-space: nowrap;
}

/* --- Responsive Breakpoints --- */
/* Desktop:  > 1024px  (default) */
/* Tablet:   768px – 1024px */
/* Mobile:   < 768px  */

@media (max-width: 1024px) {
  :root {
    --page-padding: 4vw;
  }
  .form-row {
    grid-template-columns: 1fr;
  }
}

@media (max-width: 768px) {
  :root {
    --page-padding: 5vw;
    --sp-3xl: 64px;
    --sp-2xl: 48px;
  }
  .section {
    padding: var(--sp-2xl) 0;
  }
  .modal-box {
    padding: var(--sp-lg);
  }
}

/* --- Breadcrumb Component --- */
.breadcrumb {
  display: flex;
  align-items: center;
  flex-wrap: wrap;
  gap: 12px;
  list-style: none;
  padding: 0;
  margin-bottom: var(--sp-lg);
  font-size: 0.9rem;
}

.breadcrumb-item {
  display: flex;
  align-items: center;
  gap: 12px;
  color: rgba(255, 255, 255, 0.6);
}

.breadcrumb-item a {
  color: inherit;
  text-decoration: none;
  transition: color var(--transition-fast);
}

.breadcrumb-item a:hover {
  color: var(--clr-accent);
}

.breadcrumb-item:not(:last-child)::after {
  content: "\f054"; /* FontAwesome Chevron-right */
  font-family: "Font Awesome 6 Free";
  font-weight: 900;
  font-size: 0.7rem;
  opacity: 0.4;
}

.breadcrumb-item.active {
  color: var(--clr-accent);
  font-weight: 600;
}

/* Light version for white backgrounds */
.breadcrumb-light .breadcrumb-item {
  color: var(--clr-text-muted);
}
.breadcrumb-light .breadcrumb-item.active {
  color: var(--clr-primary);
}

/* --- FAQ Accordion (Reusable) --- */
/* .faq-list {
  max-width: 900px;
  margin: 0 auto;
} */

.faq-item {
  border-bottom: 1px solid var(--clr-border);
}

.faq-header {
  padding: 24px 0;
  display: flex;
  justify-content: space-between;
  align-items: center;
  cursor: pointer;
}

.faq-header h4 {
  font-size: 1.1rem;
  font-weight: 700;
  color: var(--clr-primary-dark);
  transition: color var(--transition-fast);
}

.faq-icon {
  width: 20px;
  height: 20px;
  position: relative;
  transition: transform 0.4s;
  flex-shrink: 0;
  margin-left: 20px;
}

.faq-icon::before,
.faq-icon::after {
  content: "";
  position: absolute;
  background: var(--clr-primary-light);
  top: 50%;
  left: 50%;
  transform: translate(-50%, -50%);
}

.faq-icon::before {
  width: 12px;
  height: 2px;
}
.faq-icon::after {
  width: 2px;
  height: 12px;
  transition: transform 0.4s;
}

.faq-item.active .faq-icon::after {
  transform: translate(-50%, -50%) rotate(90deg);
  opacity: 0;
}
.faq-item.active .faq-icon {
  transform: rotate(180deg);
}
.faq-item.active h4 {
  color: var(--clr-primary);
}

.faq-body {
  max-height: 0;
  overflow: hidden;
  transition: max-height 0.5s cubic-bezier(0.4, 0, 0.2, 1);
}

.faq-item.active .faq-body {
  max-height: 500px; /* Essential fix for accordion */
}

.faq-content {
  padding-bottom: 24px;
  color: var(--clr-text-secondary);
  font-size: 0.95rem;
  line-height: 1.7;
}
nav[aria-label="main navigation"],
nav[aria-label="breadcrumb"]{
  margin-bottom: 30px;
}
.faq-page-section{
  padding: 80px 0;
}