/* ============================================================
   RLB Steel — Base Reset & Global Defaults
   重置浏览器差异 + 排版 + 容器 + 工具类 + 懒加载 + 平滑滚动
   ============================================================ */

*, *::before, *::after {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

html {
  font-size: 16px;
  scroll-behavior: smooth;          /* 全局平滑滚动 */
  -webkit-text-size-adjust: 100%;
}

body {
  font-family: var(--font-primary);
  font-size: var(--font-size-md);
  font-weight: var(--font-weight-regular);
  line-height: var(--line-height-normal);
  color: var(--color-dark);
  background-color: var(--color-white);
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  padding-top: calc(var(--top-contact-height) + var(--header-height));
  overflow-x: hidden;
}

/* ── CJK字体回退 ─────────────────────────────────────── */
[lang^="zh"],
[lang="ar"] {
  font-family: var(--font-cjk), var(--font-primary);
}

/* ── Typography ──────────────────────────────────────── */
h1, h2, h3, h4, h5, h6 {
  font-family: var(--font-primary);
  font-weight: var(--font-weight-bold);
  line-height: var(--line-height-tight);
  color: var(--color-dark);
}

h1 { font-size: var(--font-size-4xl); letter-spacing: var(--letter-spacing-tight); }
h2 { font-size: var(--font-size-3xl); }
h3 { font-size: var(--font-size-2xl); }
h4 { font-size: var(--font-size-xl);  }
h5 { font-size: var(--font-size-lg);  }
h6 { font-size: var(--font-size-md);  }

p {
  margin-bottom: var(--space-4);
  color: var(--color-dark-light);
}

a {
  color: var(--color-primary);
  text-decoration: none;
  transition: color var(--transition-fast);
}

a:hover { color: var(--color-primary-dark); }

ul, ol { list-style: none; }

img {
  max-width: 100%;
  height: auto;
  display: block;
}

button, input, select, textarea {
  font-family: inherit;
  font-size: inherit;
  line-height: inherit;
  color: inherit;
}

button {
  cursor: pointer;
  border: none;
  background: none;
}

table { border-collapse: collapse; border-spacing: 0; }

/* ── Container ───────────────────────────────────────── */
.container {
  width: 100%;
  max-width: var(--container-max);
  margin-left: auto;
  margin-right: auto;
  padding-left: var(--space-6);
  padding-right: var(--space-6);
}

.container--wide { max-width: var(--container-wide); }

/* ── Section Spacing ─────────────────────────────────── */
.section {
  padding-top: var(--space-20);
  padding-bottom: var(--space-20);
}

.section--sm {
  padding-top: var(--space-12);
  padding-bottom: var(--space-12);
}

/* ── Divider — 纤细分割线 ────────────────────────────── */
.divider {
  border: none;
  border-top: var(--divider-width) solid var(--divider-color);
  margin: 0;
}

.divider--dark { border-top-color: var(--color-dark-light); }
.divider--light { border-top-color: var(--color-white-20); }

/* ── Texture Background — SVG钢材纹理低调装饰 ────────── */
.texture-rolling {
  background-image: var(--texture-rolling);
  background-repeat: repeat;
  background-size: 200px 200px;
  opacity: var(--texture-opacity);
  position: absolute;
  inset: 0;
  pointer-events: none;
  z-index: 0;
}

.texture-cutting {
  background-image: var(--texture-cutting);
  background-repeat: repeat;
  background-size: 200px 200px;
  opacity: var(--texture-opacity);
  position: absolute;
  inset: 0;
  pointer-events: none;
  z-index: 0;
}

/* ── Lazy Load — 图片懒加载通用样式 ──────────────────── */
img[data-src] {
  opacity: 0;
  transition: opacity var(--transition-base);
}

img[data-src].loaded,
img[data-src].lazy-loaded {
  opacity: 1;
}

/* 占位骨架屏 */
.lazy-placeholder {
  background: var(--color-gray-light);
  border-radius: var(--radius-md);
  min-height: 100px;
}

/* ── Scroll Reveal — 滚动淡入上浮动画 ───────────────── */
.reveal {
  opacity: 0;
  transform: translateY(30px);
  transition: opacity var(--transition-slow),
              transform var(--transition-slow);
}

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

.reveal--left {
  opacity: 0;
  transform: translateX(-30px);
  transition: opacity var(--transition-slow),
              transform var(--transition-slow);
}

.reveal--left.visible {
  opacity: 1;
  transform: translateX(0);
}

.reveal--right {
  opacity: 0;
  transform: translateX(30px);
  transition: opacity var(--transition-slow),
              transform var(--transition-slow);
}

.reveal--right.visible {
  opacity: 1;
  transform: translateX(0);
}

/* ── Image Modal — 图片弹窗放大基础样式 ──────────────── */
.image-modal-overlay {
  position: fixed;
  inset: 0;
  background: var(--color-overlay);
  z-index: 1200;
  display: flex;
  align-items: center;
  justify-content: center;
  opacity: 0;
  visibility: hidden;
  transition: opacity var(--transition-base),
              visibility var(--transition-base);
}

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

.image-modal__close {
  position: absolute;
  top: 88px;
  right: 24px;
  width: 44px;
  height: 44px;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 0;
  color: #FFFFFF !important;
  background: #0B5CCB;
  border: 2px solid #FFFFFF;
  border-radius: 50%;
  font-size: 32px;
  font-weight: 400;
  line-height: 8;
  opacity: 1;
  box-shadow: 0 4px 14px rgba(0, 0, 0, 0.35);
  cursor: pointer;
  z-index: 1201;
  transition: transform var(--transition-fast), background var(--transition-fast);
}

.image-modal__close:hover {
  background: #084AA5;
  transform: scale(1.08);
}

@media (max-width: 576px) {
  .image-modal__close {
    top: 80px;
    right: 12px;
    width: 40px;
    height: 40px;
    font-size: 28px;
  }
}

.image-modal__content {
  max-width: 90vw;
  max-height: 90vh;
}

.image-modal__img {
  max-width: 100%;
  max-height: 90vh;
  object-fit: contain;
  border-radius: var(--radius-md);
}

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

.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;
}

/* ── Page Entrance ───────────────────────────────────── */
body {
  animation: pageIn var(--transition-slow) forwards;
}

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