/* ============================================
   Minus K 中文门户 — 星朗浩宇光电科技
   设计系统：黑白紫 · 工业极简风
   ============================================ */

/* --- CSS Variables --- */
:root {
  /* 核心色 */
  --black: #0d0d0d;
  --dark: #1a1a1a;
  --gray-700: #333333;
  --gray-400: #888888;
  --gray-200: #cccccc;
  --gray-100: #e8e8e8;
  --light: #f2f2f2;
  --white: #ffffff;

  /* 紫色系 */
  --purple: #6c3eb8;
  --purple-dark: #4a1d8c;
  --purple-light: #e8dff5;
  --purple-glow: rgba(108, 62, 184, 0.15);

  /* 间距 */
  --space-xs: 0.5rem;
  --space-sm: 1rem;
  --space-md: 1.5rem;
  --space-lg: 2.5rem;
  --space-xl: 4rem;
  --space-2xl: 6rem;

  /* 排版 */
  --font-stack: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC", "Microsoft YaHei", "Noto Sans SC", sans-serif;
  --font-mono: "SF Mono", "Cascadia Code", "Consolas", monospace;
  --text-base: 1rem;
  --text-sm: 0.875rem;
  --text-xs: 0.75rem;
  --text-lg: 1.125rem;
  --text-xl: 1.5rem;
  --text-2xl: 2rem;
  --text-3xl: 2.5rem;
  --text-hero: 3.25rem;

  /* 圆角 */
  --radius-sm: 2px;
  --radius-md: 4px;
  --radius-lg: 8px;

  /* 过渡 */
  --ease-out: cubic-bezier(0.16, 1, 0.3, 1);
  --ease-in-out: cubic-bezier(0.65, 0, 0.35, 1);
  --duration-fast: 150ms;
  --duration-normal: 300ms;
  --duration-slow: 500ms;

  /* 布局 */
  --max-width: 1200px;
  --nav-height: 100px;
}

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

html {
  scroll-behavior: smooth;
  font-size: 16px;
}

body {
  font-family: var(--font-stack);
  font-size: var(--text-base);
  line-height: 1.7;
  color: var(--black);
  background: var(--light);
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

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

a {
  text-decoration: none;
  color: inherit;
  transition: color var(--duration-fast) var(--ease-out);
}

ul {
  list-style: none;
}

/* --- Typography --- */
h1, h2, h3, h4, h5, h6 {
  font-weight: 700;
  line-height: 1.25;
  color: var(--black);
}

h1 {
  font-size: var(--text-hero);
  letter-spacing: -0.02em;
}

h2 {
  font-size: var(--text-2xl);
  letter-spacing: -0.01em;
}

h3 {
  font-size: var(--text-xl);
}

.section-label {
  display: inline-block;
  font-size: var(--text-xs);
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.12em;
  color: var(--purple);
  margin-bottom: var(--space-xs);
}

/* H2 区块标题 — 紫色下划线装饰 */
.section-title {
  font-size: var(--text-2xl);
  font-weight: 700;
  color: var(--black);
  margin-bottom: var(--space-lg);
  padding-bottom: var(--space-sm);
  position: relative;
}

.section-title::after {
  content: '';
  position: absolute;
  bottom: 0;
  left: 0;
  width: 48px;
  height: 2px;
  background: var(--purple);
}

.section-title--center {
  text-align: center;
}

.section-title--center::after {
  left: 50%;
  transform: translateX(-50%);
}

.section-title--light {
  color: var(--white);
}

.section-subtitle {
  font-size: var(--text-lg);
  color: var(--gray-400);
  margin-top: calc(var(--space-sm) * -1);
  margin-bottom: var(--space-lg);
  max-width: 600px;
}

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

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

.section--dark {
  background: var(--black);
  color: var(--white);
}

.section--dark .section-title {
  color: var(--white);
}

.section--light {
  background: var(--white);
}

.section--gray {
  background: var(--light);
}

/* --- Navigation --- */
.navbar {
  position: sticky;
  top: 0;
  z-index: 1000;
  background: var(--black);
  height: var(--nav-height);
  border-bottom: 1px solid rgba(255, 255, 255, 0.06);
  backdrop-filter: blur(10px);
}

.navbar__inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 100%;
  max-width: none;
  margin: 0 auto;
  padding: 0 var(--space-md);
}

.navbar__logo {
  display: flex;
  align-items: center;
  gap: 10px;
  font-weight: 700;
  font-size: var(--text-lg);
  color: var(--white);
  letter-spacing: -0.01em;
}

.navbar__logo-img {
  height: 32px;
  width: auto;
}

.navbar__logo-accent {
  color: var(--white);
  font-weight: 400;
  font-size: var(--text-lg);
}

.navbar__links {
  display: flex;
  align-items: center;
  gap: var(--space-lg);
}

.navbar__link {
  font-size: var(--text-base);
  font-weight: 500;
  color: var(--gray-400);
  position: relative;
  padding: var(--space-xs) 0;
  transition: color var(--duration-fast) var(--ease-out);
}

.navbar__link:hover,
.navbar__link--active {
  color: var(--white);
}

/* 当前页链接底部紫色短线 */
.navbar__link--active::after {
  content: '';
  position: absolute;
  bottom: -2px;
  left: 0;
  width: 100%;
  height: 2px;
  background: var(--purple);
  border-radius: 1px;
}

.navbar__link::after {
  content: '';
  position: absolute;
  bottom: -2px;
  left: 0;
  width: 0;
  height: 2px;
  background: var(--purple);
  border-radius: 1px;
  transition: width var(--duration-normal) var(--ease-out);
}

.navbar__link:hover::after {
  width: 100%;
}

/* 汉堡菜单按钮 */
.navbar__toggle {
  display: none;
  flex-direction: column;
  gap: 5px;
  background: none;
  border: none;
  cursor: pointer;
  padding: var(--space-xs);
}

.navbar__toggle-bar {
  width: 22px;
  height: 2px;
  background: var(--white);
  border-radius: 1px;
  transition: all var(--duration-normal) var(--ease-out);
}

.navbar__toggle.active .navbar__toggle-bar:nth-child(1) {
  transform: rotate(45deg) translate(5px, 5px);
}

.navbar__toggle.active .navbar__toggle-bar:nth-child(2) {
  opacity: 0;
}

.navbar__toggle.active .navbar__toggle-bar:nth-child(3) {
  transform: rotate(-45deg) translate(5px, -5px);
}

/* --- Hero --- */
.hero {
  position: relative;
  background: var(--black);
  background-image: url('../images/hero-banner.png');
  background-size: cover;
  background-position: center;
  background-repeat: no-repeat;
  color: var(--white);
  padding: var(--space-2xl) 0;
  overflow: hidden;
  min-height: 75vh;
  display: flex;
  align-items: center;
}

.hero__logo {
  position: absolute;
  top: 24px;
  right: 40px;
  height: 80px;
  width: auto;
  z-index: 10;
}

/* 几何线条装饰 */
.hero::before {
  content: '';
  position: absolute;
  top: -30%;
  right: -15%;
  width: 600px;
  height: 600px;
  border: 1px solid rgba(108, 62, 184, 0.2);
  border-radius: 50%;
  pointer-events: none;
}

.hero::after {
  content: '';
  position: absolute;
  bottom: -10%;
  left: -5%;
  width: 400px;
  height: 400px;
  border: 1px solid rgba(108, 62, 184, 0.1);
  border-radius: 50%;
  pointer-events: none;
}

.hero__grid {
  position: absolute;
  inset: 0;
  background-image:
    linear-gradient(rgba(255,255,255,0.02) 1px, transparent 1px),
    linear-gradient(90deg, rgba(255,255,255,0.02) 1px, transparent 1px);
  background-size: 60px 60px;
  pointer-events: none;
}

.hero__content {
  position: relative;
  z-index: 2;
  max-width: 700px;
}

.hero__label {
  display: inline-block;
  font-size: var(--text-xs);
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.15em;
  color: var(--purple);
  margin-bottom: var(--space-md);
  padding: var(--space-xs) var(--space-sm);
  border: 1px solid rgba(108, 62, 184, 0.3);
  border-radius: var(--radius-sm);
}

.hero__title {
  font-size: var(--text-hero);
  font-weight: 700;
  line-height: 1.15;
  letter-spacing: -0.02em;
  margin-bottom: var(--space-md);
  color: var(--white);
}

.hero__title span {
  color: var(--purple);
}

.hero__subtitle {
  font-size: var(--text-lg);
  color: var(--gray-400);
  line-height: 1.7;
  margin-bottom: var(--space-lg);
  max-width: 540px;
}

/* --- Buttons --- */
.btn {
  display: inline-flex;
  align-items: center;
  gap: var(--space-xs);
  padding: 0.75rem 1.75rem;
  font-size: var(--text-sm);
  font-weight: 600;
  font-family: var(--font-stack);
  border: 2px solid transparent;
  border-radius: var(--radius-sm);
  cursor: pointer;
  transition: all var(--duration-normal) var(--ease-out);
  letter-spacing: 0.02em;
  text-decoration: none;
}

.btn--primary {
  background: var(--purple);
  color: var(--white);
  border-color: var(--purple);
}

.btn--primary:hover {
  background: var(--purple-dark);
  border-color: var(--purple-dark);
}

.btn--outline {
  background: transparent;
  color: var(--white);
  border-color: rgba(255, 255, 255, 0.3);
}

.btn--outline:hover {
  border-color: var(--white);
  color: var(--white);
}

.btn--outline-dark {
  background: transparent;
  color: var(--black);
  border-color: var(--black);
}

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

.btn--sm {
  padding: 0.5rem 1.25rem;
  font-size: var(--text-xs);
}

.btn--lg {
  padding: 1rem 2.25rem;
  font-size: var(--text-base);
}

/* --- Cards --- */
.card {
  background: var(--white);
  border: 1px solid var(--gray-100);
  border-radius: var(--radius-sm);
  overflow: hidden;
  transition: all var(--duration-normal) var(--ease-out);
}

.card:hover {
  border-color: var(--purple);
  transform: translateY(-2px);
}

.card__image {
  width: 100%;
  aspect-ratio: 4 / 3;
  background: var(--white);
  display: flex;
  align-items: center;
  justify-content: center;
  overflow: hidden;
}

.card__image img {
  width: 100%;
  height: 100%;
  object-fit: contain;
}

.card__image-placeholder {
  width: 60%;
  height: 40%;
  background: linear-gradient(135deg, var(--gray-200), var(--gray-100));
  border-radius: var(--radius-sm);
  position: relative;
}

.card__image-placeholder::after {
  content: '';
  position: absolute;
  inset: 8px;
  border: 1px dashed var(--gray-400);
  border-radius: 2px;
}

.card__body {
  padding: var(--space-md);
}

.card__category {
  font-size: var(--text-xs);
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  color: var(--purple);
  margin-bottom: var(--space-xs);
}

.card__title {
  font-size: var(--text-lg);
  font-weight: 700;
  color: var(--black);
  margin-bottom: var(--space-xs);
}

.card__desc {
  font-size: var(--text-sm);
  color: var(--gray-400);
  line-height: 1.6;
  margin-bottom: var(--space-sm);
}

.card__tags {
  display: flex;
  flex-wrap: wrap;
  gap: var(--space-xs);
  margin-bottom: var(--space-sm);
}

.card__tag {
  display: inline-block;
  font-size: var(--text-xs);
  padding: 2px 10px;
  background: var(--purple-light);
  color: var(--purple-dark);
  border-radius: 3px;
  font-weight: 500;
}

.card__link {
  display: inline-flex;
  align-items: center;
  gap: 4px;
  font-size: var(--text-sm);
  font-weight: 600;
  color: var(--purple);
  transition: gap var(--duration-fast) var(--ease-out);
}

.card__link:hover {
  gap: 8px;
}

.card__link::after {
  content: '→';
  font-size: var(--text-sm);
}

/* 深色卡片变体 */
.card--dark {
  background: var(--dark);
  border-color: rgba(255,255,255,0.06);
}

.card--dark .card__title {
  color: var(--white);
}

.card--dark .card__desc {
  color: var(--gray-400);
}

.card--dark:hover {
  border-color: var(--purple);
}

/* --- Product Card (产品卡片) --- */
.product-card {
  background: var(--white);
  border: 1px solid var(--gray-100);
  border-radius: var(--radius-sm);
  overflow: hidden;
  transition: all var(--duration-normal) var(--ease-out);
  display: flex;
  flex-direction: column;
}

.product-card:hover {
  border-color: var(--purple);
  transform: translateY(-2px);
}

.product-card__image {
  width: 100%;
  aspect-ratio: 3 / 2;
  background: var(--white);
  display: flex;
  align-items: center;
  justify-content: center;
  position: relative;
  overflow: hidden;
}

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

/* 占位产品图 */
.product-card__img-placeholder {
  width: 70%;
  height: 50%;
  background: linear-gradient(135deg, #ddd, #eee);
  border-radius: var(--radius-sm);
  position: relative;
}

.product-card__img-placeholder::after {
  content: '';
  position: absolute;
  inset: 6px;
  border: 1px dashed var(--gray-400);
  border-radius: 2px;
}

.product-card__body {
  padding: var(--space-sm) var(--space-md);
  display: flex;
  flex-direction: column;
  flex: 1;
}

.product-card__model {
  font-size: var(--text-lg);
  font-weight: 700;
  color: var(--black);
  margin-bottom: 2px;
  font-family: var(--font-mono);
  letter-spacing: 0.02em;
}

.product-card__name {
  font-size: var(--text-sm);
  font-weight: 600;
  color: var(--black);
  margin-bottom: var(--space-xs);
}

.product-card__desc {
  font-size: var(--text-xs);
  color: var(--gray-400);
  line-height: 1.6;
  margin-bottom: var(--space-sm);
}

.product-card__specs {
  display: flex;
  flex-wrap: wrap;
  gap: var(--space-xs);
  margin-bottom: var(--space-md);
  margin-top: auto;
}

.product-card__spec {
  font-size: var(--text-xs);
  padding: 3px 10px;
  background: var(--purple-light);
  color: var(--purple-dark);
  border-radius: 3px;
  font-weight: 500;
}

.product-card__link {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 4px;
  padding: 0.5rem 1rem;
  font-size: var(--text-xs);
  font-weight: 600;
  color: var(--purple);
  border: 1px solid var(--purple);
  border-radius: var(--radius-sm);
  transition: all var(--duration-normal) var(--ease-out);
  width: 100%;
}

.product-card__link:hover {
  background: var(--purple);
  color: var(--white);
}

.product-card__link::after {
  content: '→';
}

/* --- Grid Systems --- */
.grid {
  display: grid;
  gap: var(--space-md);
}

.grid--2 { grid-template-columns: repeat(2, 1fr); }
.grid--3 { grid-template-columns: repeat(3, 1fr); }
.grid--4 { grid-template-columns: repeat(4, 1fr); }
.grid--auto { grid-template-columns: repeat(auto-fill, minmax(280px, 1fr)); }

/* --- Advantage Cards (产品核心优势) --- */
.advantages-grid {
  display: grid;
  grid-template-columns: repeat(5, 1fr);
  gap: var(--space-md);
}

.advantage-card {
  text-align: center;
  padding: var(--space-lg) var(--space-md);
  background: var(--white);
  border: 1px solid var(--gray-100);
  border-radius: var(--radius-sm);
  transition: all var(--duration-normal) var(--ease-out);
}

.advantage-card:hover {
  border-color: var(--purple);
  transform: translateY(-2px);
}

.advantage-card__num {
  font-size: 1.75rem;
  font-weight: 700;
  color: var(--purple);
  margin-bottom: var(--space-sm);
  font-family: var(--font-mono);
}

.advantage-card__title {
  font-size: var(--text-base);
  font-weight: 600;
  color: var(--black);
  margin-bottom: var(--space-xs);
}

.advantage-card__desc {
  font-size: var(--text-xs);
  color: var(--gray-400);
  line-height: 1.6;
}

/* --- Feature Cards (代理优势) --- */
.feature-card {
  text-align: center;
  padding: var(--space-lg) var(--space-md);
}

.feature-card__icon {
  width: 56px;
  height: 56px;
  margin: 0 auto var(--space-md);
  display: flex;
  align-items: center;
  justify-content: center;
  border: 1px solid var(--gray-200);
  border-radius: var(--radius-sm);
  font-size: 1.5rem;
}

.feature-card__title {
  font-size: var(--text-lg);
  font-weight: 600;
  margin-bottom: var(--space-xs);
  color: var(--black);
}

.feature-card__desc {
  font-size: var(--text-sm);
  color: var(--gray-400);
  line-height: 1.6;
}

/* --- Application Card (应用领域卡片) --- */
.app-card {
  background: var(--white);
  border: 1px solid var(--gray-100);
  border-radius: var(--radius-sm);
  padding: var(--space-lg);
  transition: all var(--duration-normal) var(--ease-out);
  display: flex;
  flex-direction: column;
}

.app-card:hover {
  border-color: var(--purple);
  transform: translateY(-2px);
}

.app-card__icon {
  font-size: 2rem;
  margin-bottom: var(--space-md);
}

.app-card__title {
  font-size: var(--text-base);
  font-weight: 700;
  color: var(--black);
  margin-bottom: var(--space-xs);
}

.app-card__desc {
  font-size: var(--text-sm);
  color: var(--gray-400);
  line-height: 1.6;
  flex: 1;
}

.app-card__tag {
  margin-top: var(--space-sm);
  font-size: var(--text-xs);
  color: var(--purple);
  font-weight: 500;
}

/* --- Page Header --- */
.page-header {
  background: var(--black);
  color: var(--white);
  padding: var(--space-xl) 0;
  text-align: center;
  position: relative;
  overflow: hidden;
}

.page-header::after {
  content: '';
  position: absolute;
  bottom: 0;
  left: 50%;
  transform: translateX(-50%);
  width: 60px;
  height: 2px;
  background: var(--purple);
}

.page-header__title {
  color: var(--white);
  font-size: var(--text-3xl);
  margin-bottom: var(--space-sm);
}

.page-header__subtitle {
  color: var(--gray-400);
  font-size: var(--text-lg);
  max-width: 500px;
  margin: 0 auto;
}

/* --- Category Tabs (产品分类标签) --- */
.category-tabs {
  display: flex;
  gap: var(--space-sm);
  flex-wrap: wrap;
  justify-content: center;
  margin-bottom: var(--space-xl);
  position: sticky;
  top: 100px;
  z-index: 100;
  background: var(--white);
  padding: 10px 0;
  border-bottom: 1px solid var(--gray-100);
}

.category-tab {
  padding: var(--space-sm) var(--space-md);
  font-size: var(--text-sm);
  font-weight: 500;
  font-family: var(--font-stack);
  border: 1px solid var(--gray-200);
  background: var(--white);
  color: var(--gray-700);
  border-radius: var(--radius-sm);
  cursor: pointer;
  transition: all var(--duration-normal) var(--ease-out);
}

.category-tab:hover {
  border-color: var(--purple);
  color: var(--purple);
}

.category-tab--active {
  background: var(--purple);
  color: var(--white);
  border-color: var(--purple);
}

/* --- Category Section (产品分类区块) --- */
.category-section {
  margin-bottom: var(--space-2xl);
  scroll-margin-top: 180px;
}

.category-section__header {
  margin-bottom: var(--space-lg);
  padding-bottom: var(--space-sm);
  border-bottom: 1px solid var(--gray-100);
}

.category-section__title {
  font-size: var(--text-xl);
  font-weight: 700;
  color: var(--black);
}

.category-section__desc {
  font-size: var(--text-sm);
  color: var(--gray-400);
  margin-top: var(--space-xs);
}

/* --- Technology Blocks (技术页面) --- */
.tech-intro__text {
  font-size: var(--text-base);
  color: var(--gray-400);
  line-height: 1.9;
  max-width: 800px;
}

.tech-block {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: var(--space-xl);
  align-items: center;
}

.tech-block__content {
  display: flex;
  flex-direction: column;
}

.tech-block__image {
  display: flex;
  align-items: center;
  justify-content: center;
}

.tech-block--img-right .tech-block__image {
  order: 2;
}
.tech-block--img-right .tech-block__content {
  order: 1;
}

.tech-concept {
  margin-bottom: var(--space-md);
}

.tech-concept h3 {
  font-size: var(--text-sm);
  font-weight: 700;
  color: var(--purple);
  margin-bottom: var(--space-xs);
  text-transform: uppercase;
  letter-spacing: 0.05em;
}

.tech-concept p {
  font-size: var(--text-sm);
  color: var(--gray-400);
  line-height: 1.7;
}

.tech-formula {
  display: flex;
  gap: var(--space-lg);
  margin: var(--space-sm) 0;
  padding: var(--space-sm) var(--space-md);
  background: var(--purple-light);
  border-radius: var(--radius-sm);
  font-family: var(--font-mono);
  font-size: var(--text-lg);
  font-weight: 600;
  color: var(--purple-dark);
  justify-content: center;
  flex-wrap: wrap;
}

.tech-note {
  font-size: var(--text-xs);
  color: var(--gray-400);
  line-height: 1.6;
  font-style: italic;
}

.tech-highlight {
  background: var(--purple-light);
  border: 1px solid #d4c4f0;
  border-radius: var(--radius-sm);
  padding: var(--space-md);
}

@media (max-width: 768px) {
  .tech-block {
    grid-template-columns: 1fr;
    gap: var(--space-md);
  }
  .tech-block--img-right .tech-block__image {
    order: -1;
  }
  .tech-formula {
    font-size: var(--text-base);
  }
}

/* --- Application Blocks (应用中心) --- */
.app-section {
  padding: var(--space-xl) 0;
  scroll-margin-top: 160px;
}

.app-block {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: var(--space-xl);
  align-items: center;
}

.app-block__image {
  display: flex;
  align-items: center;
  justify-content: center;
}

.app-block__image img {
  width: 100%;
  height: auto;
  max-height: 380px;
  object-fit: contain;
  display: block;
}

.app-block__placeholder {
  text-align: center;
  color: var(--gray-400);
  font-size: var(--text-sm);
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: var(--space-xs);
}

.app-block__content {
  display: flex;
  flex-direction: column;
}

.app-block__title {
  font-size: var(--text-2xl);
  font-weight: 700;
  color: var(--black);
  margin-bottom: var(--space-xs);
}

.app-block__subtitle {
  font-size: var(--text-base);
  font-weight: 600;
  color: var(--purple);
  margin-bottom: var(--space-sm);
}

.app-block__intro {
  font-size: var(--text-sm);
  color: var(--gray-400);
  line-height: 1.7;
  margin-bottom: var(--space-md);
}

/* 痛点 vs 优势对比区 */
.app-compare {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: var(--space-md);
  margin-bottom: var(--space-sm);
}

.app-compare__col {
  padding: var(--space-md);
  border-radius: var(--radius-sm);
  font-size: var(--text-sm);
  line-height: 1.6;
}

.app-compare__col--bad {
  background: #fef2f2;
  border: 1px solid #fecaca;
}

.app-compare__col--bad h4 {
  color: #991b1b;
  font-size: var(--text-sm);
  font-weight: 600;
  margin-bottom: var(--space-xs);
}

.app-compare__col--good {
  background: var(--purple-light);
  border: 1px solid #d4c4f0;
}

.app-compare__col--good h4 {
  color: var(--purple-dark);
  font-size: var(--text-sm);
  font-weight: 600;
  margin-bottom: var(--space-xs);
}

.app-compare__col ul {
  list-style: none;
  padding: 0;
}

.app-compare__col li {
  position: relative;
  padding-left: 1rem;
  margin-bottom: 4px;
  color: var(--gray-700);
}

.app-compare__col li::before {
  content: '';
  position: absolute;
  left: 0;
  top: 0.55em;
  width: 5px;
  height: 5px;
  border-radius: 50%;
}

.app-compare__col--bad li::before {
  background: #dc2626;
}

.app-compare__col--good li::before {
  background: var(--purple);
}

/* 图片在右时文本顺序不变，靠 grid order 切换 */
.app-block--img-right .app-block__image {
  order: 2;
}

.app-block--img-right .app-block__content {
  order: 1;
}

@media (max-width: 1024px) {
  .app-compare {
    grid-template-columns: 1fr;
  }
}

@media (max-width: 768px) {
  .app-block {
    grid-template-columns: 1fr;
    gap: var(--space-md);
  }
  .app-block--img-right .app-block__image {
    order: -1;
  }
  .app-block__title {
    font-size: var(--text-xl);
  }
}

/* --- About Page --- */
.about-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: var(--space-xl);
  align-items: center;
}

.about-image {
  background: var(--light);
  aspect-ratio: 4 / 3;
  display: flex;
  align-items: center;
  justify-content: center;
  border: 1px solid var(--gray-100);
  border-radius: var(--radius-sm);
  color: var(--gray-400);
  font-size: var(--text-sm);
}

.about-text h3 {
  margin-bottom: var(--space-sm);
}

.about-text p {
  margin-bottom: var(--space-md);
  color: var(--gray-700);
  line-height: 1.8;
}

/* --- Timeline (品牌故事) --- */
.timeline {
  position: relative;
  padding-left: 2rem;
  border-left: 2px solid var(--gray-100);
}

.timeline__item {
  position: relative;
  margin-bottom: var(--space-lg);
  padding-left: var(--space-md);
}

.timeline__item::before {
  content: '';
  position: absolute;
  left: -2.45rem;
  top: 0.35rem;
  width: 10px;
  height: 10px;
  background: var(--purple);
  border-radius: 50%;
}

.timeline__year {
  font-size: var(--text-xs);
  font-weight: 700;
  color: var(--purple);
  letter-spacing: 0.08em;
  margin-bottom: var(--space-xs);
}

.timeline__title {
  font-weight: 600;
  color: var(--black);
}

/* --- Contact Page --- */
.contact-section {
  padding: 60px 0 80px;
}

.contact-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 48px;
  max-width: 1100px;
  margin: 0 auto;
}

.contact-info h2 {
  font-size: 1.4rem;
  font-weight: 600;
  color: var(--black);
  margin-bottom: 12px;
}

.contact-info > p {
  font-size: 0.9rem;
  color: var(--gray-400);
  line-height: 1.7;
  margin-bottom: 28px;
}

.contact-item {
  display: flex;
  gap: 14px;
  margin-bottom: 20px;
  align-items: flex-start;
}

.contact-item-icon {
  width: 44px;
  height: 44px;
  border-radius: 50%;
  background: var(--purple-light);
  display: flex;
  align-items: center;
  justify-content: center;
  flex-shrink: 0;
  font-size: 1.1rem;
}

.contact-item-text h4 {
  font-size: 0.8rem;
  font-weight: 600;
  color: var(--purple);
  margin-bottom: 2px;
  text-transform: uppercase;
  letter-spacing: 0.05em;
}

.contact-item-text p {
  font-size: 0.9rem;
  color: var(--black);
  margin-bottom: 0;
  font-weight: 500;
}

/* --- Partners Section --- */
.partners {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: var(--space-xl);
  padding: var(--space-lg) 0;
  opacity: 0.6;
}

.partners__item {
  height: 40px;
  width: auto;
  filter: grayscale(1);
  transition: filter var(--duration-normal) var(--ease-out), opacity var(--duration-normal) var(--ease-out);
}

.partners__item:hover {
  filter: grayscale(0);
  opacity: 1;
}

/* --- Footer --- */
.footer {
  background: #1a1d20;
  color: rgba(255,255,255,0.6);
  padding: 60px 0 30px;
  border-top: 1px solid rgba(255,255,255,0.06);
}

.footer__grid {
  display: grid;
  grid-template-columns: 2fr 1fr 1fr 1fr;
  gap: 40px;
  margin-bottom: 40px;
}

.footer__brand {
  font-size: 1.25rem;
  font-weight: 600;
  color: var(--white);
  margin-bottom: 12px;
}

.footer__brand-desc {
  font-size: 0.85rem;
  color: rgba(255,255,255,0.5);
  line-height: 1.7;
  font-weight: 300;
}

.footer__heading {
  font-size: 0.85rem;
  font-weight: 600;
  color: var(--white);
  margin-bottom: 12px;
  text-transform: uppercase;
  letter-spacing: 0.04em;
  position: relative;
  padding-bottom: 8px;
}

.footer__heading::after {
  content: '';
  position: absolute;
  bottom: 0;
  left: 0;
  width: 24px;
  height: 2px;
  background: var(--purple);
}

.footer__links {
  display: flex;
  flex-direction: column;
  gap: 8px;
}

.footer__link {
  font-size: 0.85rem;
  color: rgba(255,255,255,0.5);
  transition: color var(--duration-fast) var(--ease-out);
  font-weight: 300;
}

.footer__link:hover {
  color: var(--white);
}

.footer__contact-item {
  font-size: 0.85rem;
  color: rgba(255,255,255,0.5);
  margin-bottom: 6px;
  line-height: 1.6;
  font-weight: 300;
}

.footer__bottom {
  border-top: 1px solid rgba(255,255,255,0.08);
  padding-top: 20px;
  text-align: center;
  font-size: 0.8rem;
  color: rgba(255,255,255,0.35);
  font-weight: 300;
}

/* --- Scroll Animation --- */
.fade-in {
  opacity: 0;
  transform: translateY(20px);
  transition: opacity var(--duration-slow) var(--ease-out),
              transform var(--duration-slow) var(--ease-out);
}

.fade-in.visible {
  opacity: 1;
  transform: translateY(0);
}

/* --- CTA Banner --- */
.cta-banner {
  background: var(--purple);
  color: var(--white);
  padding: var(--space-xl) 0;
  text-align: center;
}

.cta-banner__title {
  color: var(--white);
  font-size: var(--text-2xl);
  margin-bottom: var(--space-sm);
}

.cta-banner__text {
  color: rgba(255,255,255,0.8);
  margin-bottom: var(--space-lg);
  font-size: var(--text-lg);
}

/* --- Responsive --- */

/* Tablet */
@media (max-width: 1024px) {
  :root {
    --text-hero: 2.5rem;
  }

  .grid--4 { grid-template-columns: repeat(2, 1fr); }
  .grid--3 { grid-template-columns: repeat(2, 1fr); }
  .advantages-grid { grid-template-columns: repeat(3, 1fr); }
  .footer__grid {
    grid-template-columns: 1fr 1fr;
  }
  .about-grid {
    grid-template-columns: 1fr;
  }
  .contact-grid {
    grid-template-columns: 1fr;
  }
}

/* Mobile */
@media (max-width: 768px) {
  :root {
    --text-hero: 2rem;
    --text-2xl: 1.5rem;
    --text-3xl: 2rem;
    --nav-height: 80px;
  }

  .grid--2,
  .grid--3,
  .grid--4,
  .advantages-grid {
    grid-template-columns: 1fr;
  }
  .grid--auto {
    grid-template-columns: 1fr;
  }

  /* 移动端导航 */
  .navbar__links {
    position: fixed;
    top: var(--nav-height);
    left: 0;
    right: 0;
    bottom: 0;
    background: var(--black);
    flex-direction: column;
    justify-content: center;
    gap: var(--space-lg);
    transform: translateX(100%);
    transition: transform var(--duration-normal) var(--ease-in-out);
    z-index: 999;
  }

  .navbar__links.open {
    transform: translateX(0);
  }

  .navbar__toggle {
    display: flex;
  }

  .hero {
    min-height: 60vh;
    padding: var(--space-xl) 0;
  }

  .hero__title {
    font-size: var(--text-hero);
  }

  .hero::before,
  .hero::after {
    display: none;
  }

  .footer__grid {
    grid-template-columns: 1fr;
    gap: var(--space-lg);
  }

  .footer__bottom {
    flex-direction: column;
    gap: var(--space-xs);
    text-align: center;
  }

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

  .category-tabs {
    gap: var(--space-xs);
  }

  .category-tab {
    padding: var(--space-xs) var(--space-sm);
    font-size: var(--text-xs);
  }

  .partners {
    flex-wrap: wrap;
    gap: var(--space-lg);
  }
}

/* Small Mobile */
@media (max-width: 480px) {
  :root {
    --text-hero: 1.75rem;
  }

  .hero {
    min-height: 50vh;
  }

  .btn--lg {
    padding: 0.75rem 1.5rem;
    font-size: var(--text-sm);
  }

  .page-header {
    padding: var(--space-lg) 0;
  }
}