/* mirror_flow:p6_ai_generated */
/* ============================================================
   湖北平达机械制造有限公司 - 主样式表
   保存路径: style/css/style.css
   基于现代布局 (Flex/Grid) 与响应式设计
   ============================================================ */

/* ========== CSS 变量定义 ========== */
:root {
  /* 主色系 - 工业蓝 */
  --color-primary: #1a4f8a;
  --color-primary-light: #1e5fbb;
  --color-primary-dark: #143b66;
  --color-primary-hover: #2055a4;
  --color-primary-active: #0f2f52;

  /* 辅助色 */
  --color-accent: #e8831a;
  --color-accent-hover: #c96e15;
  --color-accent-light: #f4a64b;

  /* 中性色 */
  --color-white: #ffffff;
  --color-black: #1a1a1a;
  --color-gray-50: #f8f9fa;
  --color-gray-100: #f0f2f5;
  --color-gray-200: #e2e6ea;
  --color-gray-300: #ced4da;
  --color-gray-400: #adb5bd;
  --color-gray-500: #6c757d;
  --color-gray-600: #495057;
  --color-gray-700: #343a40;
  --color-gray-800: #212529;
  --color-gray-900: #121416;

  /* 语义色 */
  --color-success: #28a745;
  --color-warning: #ffc107;
  --color-danger: #dc3545;
  --color-info: #17a2b8;

  /* 字体 */
  --font-family-base: "Microsoft YaHei", "微软雅黑", "PingFang SC", "Helvetica Neue", Arial, sans-serif;
  --font-family-heading: "Microsoft YaHei", "微软雅黑", "PingFang SC", "Helvetica Neue", Arial, sans-serif;
  --font-family-number: "Arial", "Helvetica Neue", sans-serif;

  --font-size-xs: 0.75rem;
  --font-size-sm: 0.875rem;
  --font-size-base: 1rem;
  --font-size-md: 1.125rem;
  --font-size-lg: 1.25rem;
  --font-size-xl: 1.5rem;
  --font-size-2xl: 1.75rem;
  --font-size-3xl: 2rem;
  --font-size-4xl: 2.5rem;

  --font-weight-light: 300;
  --font-weight-normal: 400;
  --font-weight-medium: 500;
  --font-weight-semibold: 600;
  --font-weight-bold: 700;

  --line-height-tight: 1.25;
  --line-height-normal: 1.6;
  --line-height-relaxed: 1.75;

  /* 间距 */
  --spacing-xs: 0.25rem;
  --spacing-sm: 0.5rem;
  --spacing-md: 1rem;
  --spacing-lg: 1.5rem;
  --spacing-xl: 2rem;
  --spacing-2xl: 3rem;
  --spacing-3xl: 4rem;
  --spacing-4xl: 5rem;

  /* 边框与圆角 */
  --border-radius-sm: 4px;
  --border-radius-md: 6px;
  --border-radius-lg: 10px;
  --border-radius-xl: 16px;
  --border-radius-round: 50%;

  --border-width-thin: 1px;
  --border-width-medium: 2px;
  --border-width-thick: 3px;

  --border-color-light: var(--color-gray-200);
  --border-color-base: var(--color-gray-300);
  --border-color-dark: var(--color-gray-400);

  /* 阴影 */
  --shadow-sm: 0 1px 3px rgba(0, 0, 0, 0.06), 0 1px 2px rgba(0, 0, 0, 0.04);
  --shadow-md: 0 4px 12px rgba(0, 0, 0, 0.08), 0 2px 4px rgba(0, 0, 0, 0.04);
  --shadow-lg: 0 10px 30px rgba(0, 0, 0, 0.1), 0 4px 8px rgba(0, 0, 0, 0.05);
  --shadow-xl: 0 20px 50px rgba(0, 0, 0, 0.12), 0 8px 16px rgba(0, 0, 0, 0.06);

  /* 过渡 */
  --transition-fast: 0.15s ease;
  --transition-base: 0.25s ease;
  --transition-slow: 0.4s ease;

  /* 容器宽度 */
  --container-max-width: 1200px;
  --container-padding: 1.25rem;

  /* 导航高度 */
  --header-height: 72px;
  --header-height-mobile: 56px;

  /* 层级 */
  --z-index-dropdown: 100;
  --z-index-sticky: 200;
  --z-index-fixed: 300;
  --z-index-modal-backdrop: 400;
  --z-index-modal: 500;
  --z-index-popover: 600;
  --z-index-tooltip: 700;
}

/* ========== 全局重置 ========== */
*,
*::before,
*::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

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

body {
  font-family: var(--font-family-base);
  font-size: var(--font-size-base);
  font-weight: var(--font-weight-normal);
  line-height: var(--line-height-normal);
  color: var(--color-gray-800);
  background-color: var(--color-white);
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  overflow-x: hidden;
}

img {
  max-width: 100%;
  height: auto;
  display: block;
  border-style: none;
}

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

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

ul,
ol {
  list-style: none;
}

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

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

h1, h2, h3, h4, h5, h6 {
  font-family: var(--font-family-heading);
  font-weight: var(--font-weight-bold);
  line-height: var(--line-height-tight);
  color: var(--color-gray-900);
}

h1 { font-size: var(--font-size-4xl); }
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); }

/* ========== 工具类 ========== */
.container {
  width: 100%;
  max-width: var(--container-max-width);
  margin-left: auto;
  margin-right: auto;
  padding-left: var(--container-padding);
  padding-right: var(--container-padding);
}

.clearfix::after {
  content: "";
  display: table;
  clear: both;
}

.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;
}

.text-center { text-align: center; }
.text-left { text-align: left; }
.text-right { text-align: right; }

/* ========== 头部区域 ========== */
.site-header {
  position: sticky;
  top: 0;
  z-index: var(--z-index-sticky);
  background-color: var(--color-white);
  box-shadow: var(--shadow-sm);
  height: var(--header-height);
  transition: box-shadow var(--transition-base);
}

.site-header.scrolled {
  box-shadow: var(--shadow-md);
}

.header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 100%;
  max-width: var(--container-max-width);
  margin: 0 auto;
  padding: 0 var(--container-padding);
}

/* Logo */
.site-logo {
  display: flex;
  align-items: center;
  flex-shrink: 0;
}

.site-logo img {
  height: 48px;
  width: auto;
}

.site-logo .logo-text {
  margin-left: var(--spacing-md);
}

.site-logo .logo-title {
  font-size: var(--font-size-lg);
  font-weight: var(--font-weight-bold);
  color: var(--color-primary-dark);
  line-height: 1.2;
}

.site-logo .logo-subtitle {
  font-size: var(--font-size-xs);
  color: var(--color-gray-500);
  line-height: 1.4;
}

/* 主导航 */
.main-nav {
  display: flex;
  align-items: center;
}

.main-nav-list {
  display: flex;
  align-items: center;
  gap: 0;
}

.main-nav-item {
  position: relative;
}

.main-nav-link {
  display: block;
  padding: 0.6rem 1.1rem;
  font-size: var(--font-size-sm);
  font-weight: var(--font-weight-medium);
  color: var(--color-gray-700);
  white-space: nowrap;
  border-bottom: 2px solid transparent;
  transition: color var(--transition-fast), border-color var(--transition-fast);
}

.main-nav-link:hover,
.main-nav-link.active {
  color: var(--color-primary);
  border-bottom-color: var(--color-primary);
}

/* 下拉菜单 */
.main-nav-item.has-dropdown {
  position: relative;
}

.main-nav-item.has-dropdown > .main-nav-link::after {
  content: "";
  display: inline-block;
  width: 0;
  height: 0;
  margin-left: 0.35em;
  vertical-align: 0.15em;
  border-top: 4px solid currentColor;
  border-right: 4px solid transparent;
  border-left: 4px solid transparent;
  transition: transform var(--transition-fast);
}

.main-nav-item.has-dropdown:hover > .main-nav-link::after {
  transform: rotate(180deg);
}

.sub-nav {
  position: absolute;
  top: 100%;
  left: 0;
  min-width: 180px;
  background-color: var(--color-white);
  border-radius: var(--border-radius-md);
  box-shadow: var(--shadow-lg);
  opacity: 0;
  visibility: hidden;
  transform: translateY(8px);
  transition: opacity var(--transition-base), visibility var(--transition-base), transform var(--transition-base);
  z-index: var(--z-index-dropdown);
  padding: var(--spacing-sm) 0;
}

.main-nav-item.has-dropdown:hover .sub-nav {
  opacity: 1;
  visibility: visible;
  transform: translateY(0);
}

.sub-nav-item a {
  display: block;
  padding: 0.6rem 1.25rem;
  font-size: var(--font-size-sm);
  color: var(--color-gray-600);
  transition: background-color var(--transition-fast), color var(--transition-fast);
}

.sub-nav-item a:hover {
  background-color: var(--color-gray-50);
  color: var(--color-primary);
}

/* 移动端菜单按钮 */
.mobile-menu-toggle {
  display: none;
  flex-direction: column;
  justify-content: center;
  align-items: center;
  width: 40px;
  height: 40px;
  cursor: pointer;
  background: none;
  border: none;
  padding: 6px;
}

.mobile-menu-toggle span {
  display: block;
  width: 24px;
  height: 2px;
  background-color: var(--color-gray-700);
  border-radius: 2px;
  transition: transform var(--transition-base), opacity var(--transition-base);
}

.mobile-menu-toggle span:nth-child(2) {
  margin: 5px 0;
}

.mobile-menu-toggle.active span:nth-child(1) {
  transform: translateY(7px) rotate(45deg);
}

.mobile-menu-toggle.active span:nth-child(2) {
  opacity: 0;
}

.mobile-menu-toggle.active span:nth-child(3) {
  transform: translateY(-7px) rotate(-45deg);
}

/* ========== Banner 区域 ========== */
.banner-section {
  position: relative;
  background-color: var(--color-gray-800);
  overflow: hidden;
}

.banner-slider {
  position: relative;
  width: 100%;
}

.banner-slide {
  position: relative;
  width: 100%;
  min-height: 420px;
  max-height: 600px;
  overflow: hidden;
}

.banner-slide img {
  width: 100%;
  height: 100%;
  object-fit: cover;
}

.banner-overlay {
  position: absolute;
  inset: 0;
  background: linear-gradient(to bottom, rgba(0,0,0,0.2) 0%, rgba(0,0,0,0.5) 100%);
}

.banner-content {
  position: absolute;
  bottom: 18%;
  left: 50%;
  transform: translateX(-50%);
  text-align: center;
  color: var(--color-white);
  z-index: 1;
  width: 90%;
  max-width: 700px;
}

.banner-content h2 {
  font-size: clamp(1.5rem, 4vw, 2.8rem);
  font-weight: var(--font-weight-bold);
  color: var(--color-white);
  margin-bottom: var(--spacing-md);
  text-shadow: 0 2px 8px rgba(0,0,0,0.3);
}

.banner-content p {
  font-size: clamp(0.9rem, 2vw, 1.2rem);
  color: rgba(255,255,255,0.9);
  margin-bottom: var(--spacing-lg);
  text-shadow: 0 1px 4px rgba(0,0,0,0.3);
}

.banner-content .btn {
  display: inline-block;
  padding: 0.75rem 2rem;
  font-size: var(--font-size-base);
  font-weight: var(--font-weight-medium);
  border-radius: var(--border-radius-md);
  transition: all var(--transition-base);
}

.banner-content .btn-primary {
  background-color: var(--color-primary);
  color: var(--color-white);
}

.banner-content .btn-primary:hover {
  background-color: var(--color-primary-hover);
  color: var(--color-white);
  transform: translateY(-2px);
  box-shadow: var(--shadow-md);
}

.banner-content .btn-outline {
  background-color: transparent;
  color: var(--color-white);
  border: 2px solid var(--color-white);
  margin-left: var(--spacing-md);
}

.banner-content .btn-outline:hover {
  background-color: var(--color-white);
  color: var(--color-primary-dark);
}

/* Banner 指示器 */
.banner-indicators {
  position: absolute;
  bottom: 1.5rem;
  left: 50%;
  transform: translateX(-50%);
  display: flex;
  gap: 0.5rem;
  z-index: 2;
}

.banner-indicator {
  width: 12px;
  height: 12px;
  border-radius: var(--border-radius-round);
  background-color: rgba(255,255,255,0.5);
  cursor: pointer;
  transition: background-color var(--transition-fast), transform var(--transition-fast);
  border: 2px solid transparent;
}

.banner-indicator.active {
  background-color: var(--color-white);
  transform: scale(1.2);
  border-color: var(--color-primary-light);
}

/* ========== 通用区块 ========== */
.section {
  padding: var(--spacing-3xl) 0;
}

.section-gray {
  background