/* ============================================
   糖护科技官网 — 全局样式
   Design Reference: Apple.com style
   Palette: Black / White / Gray / Subtle Blue
   FORBIDDEN: Red / Green elements
   ============================================ */

/* --- CSS Variables --- */
:root {
  /* Colors */
  --color-bg: #ffffff;
  --color-bg-secondary: #f5f5f7;
  --color-bg-tertiary: #fbfbfd;
  --color-text-primary: #1d1d1f;
  --color-text-secondary: #6e6e73;
  --color-text-tertiary: #86868b;
  --color-text-link: #0066cc;
  --color-text-link-hover: #004499;
  --color-border: #d2d2d7;
  --color-border-light: #e8e8ed;
  --color-nav-bg: #ffffff;
  --color-nav-border: rgba(0, 0, 0, 0.08);
  --color-blue: #2997ff;
  --color-blue-dark: #0071e3;
  --color-blue-bg: #f0f7ff;
  --color-accent: #0066cc;
  --color-overlay: rgba(0, 0, 0, 0.4);

  /* Typography */
  --font-family-zh: -apple-system, 'PingFang SC', 'Noto Sans SC', 'Helvetica Neue', 'Microsoft YaHei', sans-serif;
  --font-family-en: -apple-system, 'SF Pro Display', 'SF Pro Text', 'Helvetica Neue', Arial, sans-serif;
  --font-weight-regular: 400;
  --font-weight-medium: 500;
  --font-weight-semibold: 600;
  --font-weight-bold: 700;

  /* Font sizes (responsive base) */
  --fs-hero: clamp(2rem, 4vw, 3.25rem);
  --fs-h1: clamp(1.75rem, 3.5vw, 2.5rem);
  --fs-h2: clamp(1.5rem, 3vw, 2rem);
  --fs-h3: clamp(1.25rem, 2.5vw, 1.5rem);
  --fs-h4: clamp(1rem, 2vw, 1.25rem);
  --fs-body: clamp(0.9375rem, 1.2vw, 1.0625rem);
  --fs-caption: clamp(0.8125rem, 1vw, 0.9375rem);
  --fs-small: 0.8125rem;
  --fs-nav: clamp(0.875rem, 1vw, 0.9375rem);

  /* Spacing */
  --spacing-xs: 8px;
  --spacing-sm: 16px;
  --spacing-md: 24px;
  --spacing-lg: 40px;
  --spacing-xl: 64px;
  --spacing-2xl: 80px;
  --spacing-3xl: 120px;

  /* Layout */
  --max-width: 1200px;
  --nav-height: 48px;
  --section-padding: 80px 0;

  /* Radius */
  --radius-sm: 8px;
  --radius-md: 12px;
  --radius-lg: 18px;
  --radius-xl: 24px;

  /* Shadows */
  --shadow-sm: 0 2px 8px rgba(0, 0, 0, 0.04);
  --shadow-md: 0 4px 16px rgba(0, 0, 0, 0.08);
  --shadow-lg: 0 8px 32px rgba(0, 0, 0, 0.12);
  --shadow-card: 0 2px 12px rgba(0, 0, 0, 0.06);

  /* Transitions */
  --transition-fast: 0.15s ease;
  --transition-normal: 0.3s ease;
  --transition-slow: 0.5s ease;
}

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

html {
  font-size: 16px;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  scroll-behavior: smooth;
}

body {
  font-family: var(--font-family-zh);
  font-weight: var(--font-weight-regular);
  color: var(--color-text-primary);
  background-color: var(--color-bg);
  line-height: 1.6;
  overflow-x: hidden;
}

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

a:hover {
  color: var(--color-text-link-hover);
}

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

ul, ol {
  list-style: none;
}

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

/* --- Utility Classes --- */
.container {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0 var(--spacing-md);
}

.section {
  padding: var(--section-padding);
}

.section--gray {
  background-color: var(--color-bg-secondary);
}

.section-title {
  font-size: var(--fs-h2);
  font-weight: var(--font-weight-bold);
  color: var(--color-text-primary);
  text-align: center;
  margin-bottom: var(--spacing-sm);
  letter-spacing: -0.01em;
}

.section-subtitle {
  font-size: var(--fs-body);
  color: var(--color-text-secondary);
  text-align: center;
  margin-bottom: var(--spacing-lg);
  max-width: 680px;
  margin-left: auto;
  margin-right: auto;
}

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

/* --- Navigation --- */
.nav {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  height: var(--nav-height);
  background: var(--color-nav-bg);
  backdrop-filter: saturate(180%) blur(20px);
  -webkit-backdrop-filter: saturate(180%) blur(20px);
  border-bottom: 1px solid var(--color-nav-border);
  z-index: 1000;
  transition: background var(--transition-normal);
}

.nav__inner {
  max-width: 1024px;
  margin: 0 auto;
  height: 100%;
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 0 var(--spacing-md);
}

.nav__logo {
  display: flex;
  align-items: center;
  gap: 8px;
  font-weight: var(--font-weight-semibold);
  font-size: var(--fs-nav);
  color: var(--color-text-primary);
  text-decoration: none;
  flex-shrink: 0;
}

.nav__logo img {
  height: 28px;
  width: auto;
}

.nav__logo-text {
  font-size: 1rem;
  font-weight: var(--font-weight-semibold);
  white-space: nowrap;
}

.nav__links {
  display: flex;
  align-items: center;
  gap: 0;
}

.nav__link {
  font-size: var(--fs-nav);
  color: var(--color-text-primary);
  text-decoration: none;
  padding: 0 12px;
  height: var(--nav-height);
  display: flex;
  align-items: center;
  transition: color var(--transition-fast);
  white-space: nowrap;
  opacity: 0.8;
}

.nav__link:hover,
.nav__link--active {
  opacity: 1;
  color: var(--color-text-primary);
}

.nav__link--active {
  font-weight: var(--font-weight-medium);
}

.nav__actions {
  display: flex;
  align-items: center;
  gap: 12px;
  flex-shrink: 0;
}

.nav__lang-btn {
  font-size: var(--fs-small);
  color: var(--color-text-secondary);
  padding: 4px 10px;
  border-radius: 20px;
  border: 1px solid var(--color-border);
  background: transparent;
  transition: all var(--transition-fast);
  white-space: nowrap;
}

.nav__lang-btn:hover {
  color: var(--color-text-primary);
  border-color: var(--color-text-primary);
}

.nav__lang-btn--disabled {
  opacity: 0.4;
  cursor: not-allowed;
}

.nav__lang-btn--disabled:hover {
  color: var(--color-text-secondary);
  border-color: var(--color-border);
}

.nav__login-btn {
  font-size: var(--fs-small);
  color: var(--color-blue-dark);
  padding: 5px 14px;
  border-radius: 20px;
  border: 1px solid var(--color-blue-dark);
  background: transparent;
  transition: all var(--transition-fast);
  white-space: nowrap;
}

.nav__login-btn:hover {
  background: var(--color-blue-dark);
  color: #fff;
}

.nav__user-avatar {
  width: 28px;
  height: 28px;
  border-radius: 50%;
  background: var(--color-bg-secondary);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 14px;
  color: var(--color-text-secondary);
  cursor: pointer;
}

/* Mobile nav toggle */
.nav__mobile-toggle {
  display: none;
  flex-direction: column;
  gap: 5px;
  padding: 8px;
  cursor: pointer;
}

.nav__mobile-toggle span {
  width: 18px;
  height: 1.5px;
  background: var(--color-text-primary);
  transition: all var(--transition-fast);
}

/* --- Mobile Navigation Menu --- */
.mobile-nav {
  display: none;
  position: fixed;
  top: var(--nav-height);
  left: 0;
  right: 0;
  bottom: 0;
  background: var(--color-bg);
  z-index: 999;
  padding: var(--spacing-md);
  overflow-y: auto;
}

.mobile-nav.is-open {
  display: block;
}

.mobile-nav__link {
  display: block;
  font-size: 1.25rem;
  font-weight: var(--font-weight-medium);
  color: var(--color-text-primary);
  padding: 16px 0;
  border-bottom: 1px solid var(--color-border-light);
  text-decoration: none;
}

.mobile-nav__actions {
  display: flex;
  gap: 12px;
  margin-top: 24px;
}

/* --- Hero Banner --- */
.banner {
  position: relative;
  width: 100%;
  height: 387px;
  overflow: hidden;
  margin-top: var(--nav-height);
  background: #000;
}

.banner__slides {
  display: flex;
  width: 100%;
  height: 100%;
  transition: transform 0.6s cubic-bezier(0.25, 0.1, 0.25, 1);
}

.banner__slide {
  min-width: 100%;
  height: 100%;
  display: flex;
  align-items: center;
  justify-content: center;
  position: relative;
}

.banner__slide-img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  opacity: 0.7;
}

.banner__slide-content {
  position: absolute;
  text-align: center;
  color: #fff;
  z-index: 2;
  padding: 0 var(--spacing-md);
}

/* Split banner (slide 3: left text + right image) */
.banner__slide--split,.banner__slide--poster {
  display: flex;
  align-items: center;
  justify-content: flex-start;
  gap: 60px;
  padding: 0 60px 0 3cm;
}

.banner__slide--split .banner__slide-content {
  position: relative;
  flex: 1;
  max-width: 480px;
  text-align: left;
  padding-left: 0;
}

.banner__slide--split .banner__slide-image {
  position: relative;
  flex: 1;
  max-width: 520px;
  z-index: 2;
}

.banner__slide-poster-img-wrap {
  padding: 0;
  border-radius: 12px;
  background: transparent;
  display: flex;
  justify-content: center;
  align-items: center;
  box-shadow: none;
  border: none;
}

.banner__slide-poster-img-wrap img {
  max-width: 100%;
  max-height: 300px;
  object-fit: contain;
  border-radius: 8px;
}

.banner__slide-content--left {
  text-align: left;
  padding-left: 0;
}

.banner__poster-btn {
  display: inline-block;
  margin-top: 24px;
  padding: 12px 36px;
  background: transparent;
  color: #f5a623;
  font-size: 16px;
  font-weight: 600;
  border: 2px solid #f5a623;
  border-radius: 8px;
  cursor: pointer;
  text-decoration: none;
  transition: all 0.2s;
}

.banner__poster-btn:hover {
  background: #f5a623;
  color: #fff;
  transform: translateY(-1px);
}

.banner__slide-title {
  font-size: var(--fs-hero);
  font-weight: var(--font-weight-bold);
  letter-spacing: -0.02em;
  margin-bottom: 16px;
  text-shadow: 0 2px 20px rgba(0,0,0,0.3);
}

.banner__slide-desc {
  font-size: var(--fs-h4);
  font-weight: var(--font-weight-regular);
  opacity: 0.9;
  text-shadow: 0 1px 10px rgba(0,0,0,0.3);
}

/* Banner indicators */
.banner__indicators {
  position: absolute;
  bottom: 28px;
  left: 50%;
  transform: translateX(-50%);
  display: flex;
  gap: 8px;
  z-index: 3;
}

.banner__indicator {
  width: 8px;
  height: 8px;
  border-radius: 50%;
  background: rgba(255, 255, 255, 0.4);
  cursor: pointer;
  transition: all var(--transition-fast);
}

.banner__indicator--active {
  background: #fff;
  width: 24px;
  border-radius: 4px;
}

/* Banner arrows */
.banner__arrow {
  position: absolute;
  top: 50%;
  transform: translateY(-50%);
  width: 44px;
  height: 44px;
  border-radius: 50%;
  background: rgba(255, 255, 255, 0.15);
  backdrop-filter: blur(10px);
  display: flex;
  align-items: center;
  justify-content: center;
  color: #fff;
  font-size: 20px;
  cursor: pointer;
  z-index: 3;
  transition: background var(--transition-fast);
  border: 1px solid rgba(255, 255, 255, 0.2);
}

.banner__arrow:hover {
  background: rgba(255, 255, 255, 0.25);
}

.banner__arrow--prev {
  left: 24px;
}

.banner__arrow--next {
  right: 24px;
}

/* --- Product Section (Homepage) --- */
.products-section {
  padding: var(--spacing-2xl) 0 12px;
}

.products-block {
  margin-bottom: var(--spacing-3xl);
}

/* 企业服务：与上方智能硬件区域同宽（不限制max-width） */
.products-block--full .products-grid--1 {
  max-width: none;
}

.products-block__header {
  text-align: center;
  margin-bottom: var(--spacing-lg);
}

.products-block__title {
  font-size: var(--fs-h2);
  font-weight: var(--font-weight-bold);
  color: var(--color-text-primary);
  margin-bottom: 8px;
  letter-spacing: -0.01em;
}

.products-block__desc {
  font-size: var(--fs-body);
  color: var(--color-text-secondary);
}

.products-grid {
  display: grid;
  gap: var(--spacing-md);
}

.products-grid--3 {
  grid-template-columns: repeat(3, 1fr);
}

.products-grid--2 {
  grid-template-columns: repeat(2, 1fr);
}

.products-grid--1 {
  grid-template-columns: 1fr;
  max-width: 800px;
  margin: 0 auto;
}

/* --- Product Card --- */
.product-card {
  background: var(--color-bg-tertiary);
  border-radius: var(--radius-lg);
  overflow: hidden;
  transition: transform var(--transition-normal), box-shadow var(--transition-normal);
}

.product-card:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-md);
}

.product-card__image {
  width: 100%;
  height: 322px;
  background: #f5f5f7;
  display: flex;
  align-items: center;
  justify-content: center;
  overflow: hidden;
}

.product-card__image--full {
  height: auto;
  padding: 0;
}
.product-card__image--full img {
  width: 100%;
  height: auto;
  object-fit: cover;
}

.product-card__image--apps {
  display: flex;
  align-items: center;
  gap: 12px;
  padding: 20px 16px 20px 24px;
  justify-content: space-between;
  height: 340px;
  background: #F0F5FF;
}

.product-card__app-icon {
  width: 64px;
  height: 64px;
  flex-shrink: 0;
  margin-right: 8px;
  border-radius: 14px;
  object-fit: contain;
  box-shadow: 0 2px 10px rgba(0,0,0,0.08);
}

.product-card__app-screens {
  display: flex;
  flex: 1;
  min-width: 0;
  justify-content: center;
  margin-left: -10px;
}

.product-card__app-screens img {
  height: 280px;
  width: auto;
  max-width: 40%;
  border-radius: 14px;
  object-fit: contain;
  box-shadow: 0 4px 16px rgba(0,0,0,0.12);
  transition: transform 0.3s ease;
}

.product-card__app-screens img:first-child {
  transform: rotate(-3deg);
  z-index: 2;
}

.product-card__app-screens img:last-child {
  transform: rotate(3deg);
  z-index: 1;
}

.product-card:hover .product-card__app-screens img:first-child {
  transform: rotate(-1deg) scale(1.02);
}

.product-card:hover .product-card__app-screens img:last-child {
  transform: rotate(1deg) scale(1.02);
}

.product-card__btn--side {
  display: block;
  flex-shrink: 0;
  margin-left: 6px;
  padding: 12px 8px;
  border-radius: 8px;
  font-size: 13px;
  font-weight: 600;
  color: var(--color-blue-dark);
  background: #fff;
  border: 2px solid var(--color-blue-dark);
  white-space: nowrap;
  line-height: 1.8;
  box-shadow: 0 2px 8px rgba(0,113,227,0.15);
}

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

.product-card__placeholder {
  font-size: var(--fs-h3);
  color: var(--color-text-tertiary);
}

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

.product-card__body--compact {
  padding: 12px var(--spacing-md);
}

.product-card__body--compact .product-card__name {
  margin-bottom: 4px;
}

.product-card__body--compact .product-card__brief {
  margin-bottom: 0;
}

.product-card__body--row {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 12px;
}

.product-card__body--row .product-card__text {
  flex: 1;
  min-width: 0;
}

.product-card__btn--right {
  flex-shrink: 0;
  align-self: center;
}

.product-card__name {
  font-size: var(--fs-h4);
  font-weight: var(--font-weight-semibold);
  color: var(--color-text-primary);
  margin-bottom: 8px;
}

.product-card__brief {
  font-size: var(--fs-caption);
  color: var(--color-text-secondary);
  line-height: 1.5;
  margin-bottom: 16px;
}

.product-card__btn {
  display: inline-block;
  font-size: var(--fs-caption);
  color: var(--color-blue-dark);
  padding: 8px 20px;
  border-radius: 20px;
  border: 1px solid var(--color-blue-dark);
  background: transparent;
  transition: all var(--transition-fast);
}

.product-card__btn:hover {
  background: var(--color-blue-dark);
  color: #fff;
}

/* --- Product Detail Page --- */
.product-detail {
  padding-top: calc(var(--nav-height) + var(--spacing-xl));
}

.product-hero {
  display: flex;
  align-items: center;
  gap: var(--spacing-xl);
  padding: var(--spacing-xl) 0;
}

.product-hero__image {
  flex: 1;
  max-width: 350px;
  aspect-ratio: 1;
  background: var(--color-bg-secondary);
  border-radius: var(--radius-lg);
  overflow: hidden;
  display: flex;
  align-items: center;
  justify-content: center;
}

.product-hero__image img {
  width: 100%;
  height: 100%;
  object-fit: cover;
}

.product-hero__info {
  flex: 1;
}

.product-hero__name {
  font-size: var(--fs-h1);
  font-weight: var(--font-weight-bold);
  color: var(--color-text-primary);
  margin-bottom: 16px;
  letter-spacing: -0.01em;
}

.product-hero__name--up {
  margin-top: -1.2em;
}

/* SPUG Selling Points */
.spug-selling-points {
  list-style: none;
  padding: 0 0 0 2em;
  margin: 0;
  display: flex;
  flex-direction: column;
  gap: 10px;
}

.spug-selling-points li {
  font-size: var(--fs-body);
  color: var(--color-text-secondary);
  line-height: 1.6;
  padding-left: 1.4em;
  position: relative;
}

.spug-selling-points li::before {
  content: '';
  position: absolute;
  left: 0;
  top: 0.55em;
  width: 8px;
  height: 8px;
  border-radius: 50%;
  background: #3a7bd5;
}

.product-hero__brief {
  font-size: var(--fs-body);
  color: var(--color-text-secondary);
  line-height: 1.7;
  margin-bottom: var(--spacing-md);
}

/* Features */
.features {
  padding: var(--spacing-2xl) 0;
}

.features__title {
  font-size: var(--fs-h2);
  font-weight: var(--font-weight-bold);
  text-align: center;
  margin-bottom: var(--spacing-lg);
}

.features-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: var(--spacing-md);
}

.feature-card {
  text-align: center;
  padding: var(--spacing-md);
  border-radius: var(--radius-md);
  background: var(--color-bg-tertiary);
}

.feature-card__icon {
  width: 48px;
  height: 48px;
  margin: 0 auto 16px;
  background: var(--color-blue-bg);
  border-radius: var(--radius-sm);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 24px;
}

.feature-card__title {
  font-size: var(--fs-h4);
  font-weight: var(--font-weight-semibold);
  color: var(--color-text-primary);
  margin-bottom: 8px;
}

.feature-card__desc {
  font-size: var(--fs-caption);
  color: var(--color-text-secondary);
  line-height: 1.5;
}

/* Params table */
.params-section {
  padding: var(--spacing-2xl) 0;
}

.params-section__title {
  font-size: var(--fs-h2);
  font-weight: var(--font-weight-bold);
  text-align: center;
  margin-bottom: var(--spacing-lg);
}

.params-table {
  max-width: 700px;
  margin: 0 auto;
  border-collapse: collapse;
  width: 100%;
}

.params-table__row {
  border-bottom: 1px solid var(--color-border-light);
}

.params-table__row:last-child {
  border-bottom: none;
}

.params-table__label {
  padding: 14px 16px;
  font-size: var(--fs-caption);
  color: var(--color-text-secondary);
  width: 180px;
  background: var(--color-bg-secondary);
}

.params-table__value {
  padding: 14px 16px;
  font-size: var(--fs-caption);
  color: var(--color-text-primary);
}

/* --- Footer --- */
.footer {
  background: var(--color-bg-secondary);
  border-top: 1px solid var(--color-border-light);
  padding: var(--spacing-xl) 0 var(--spacing-lg);
}

.footer__inner {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0 var(--spacing-md);
}

.footer__top {
  display: flex;
  justify-content: space-between;
  align-items: flex-start;
  margin-bottom: var(--spacing-lg);
  padding-bottom: var(--spacing-lg);
  border-bottom: 1px solid var(--color-border-light);
}

.footer__qualifications {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  flex: 1;
}

.footer__qual-link {
  font-size: var(--fs-small);
  color: var(--color-text-secondary);
  padding: 6px 12px;
  border: 1px solid var(--color-border);
  border-radius: 4px;
  text-decoration: none;
  transition: all var(--transition-fast);
}

.footer__qual-link:hover {
  color: var(--color-text-primary);
  border-color: var(--color-text-primary);
}

.footer__social {
  display: flex;
  gap: 10px;
  align-items: center;
}

.footer__social-link {
  width: 36px;
  height: 36px;
  border-radius: 50%;
  background: var(--color-bg);
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--color-text-secondary);
  font-size: 16px;
  text-decoration: none;
  transition: all var(--transition-fast);
}

.footer__social-link:hover {
  color: var(--color-text-primary);
  box-shadow: var(--shadow-sm);
}

.footer__bottom {
  display: flex;
  justify-content: space-between;
  align-items: center;
  flex-wrap: wrap;
  gap: var(--spacing-sm);
}

.footer__copyright {
  font-size: var(--fs-small);
  color: var(--color-text-tertiary);
}

.footer__links {
  display: flex;
  gap: 24px;
}

.footer__link {
  font-size: var(--fs-small);
  color: var(--color-text-tertiary);
  text-decoration: none;
}

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

/* --- Page Hero --- */
.page-hero {
  margin-top: var(--nav-height);
  padding: var(--spacing-2xl) 0 var(--spacing-lg);
  text-align: center;
}

.page-hero__title {
  font-size: var(--fs-h1);
  font-weight: var(--font-weight-bold);
  color: var(--color-text-primary);
  margin-bottom: 12px;
  letter-spacing: -0.01em;
}

.page-hero__subtitle {
  font-size: var(--fs-body);
  color: var(--color-text-secondary);
  max-width: 600px;
  margin: 0 auto;
}

/* --- Buttons --- */
.btn {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 10px 24px;
  border-radius: 24px;
  font-size: var(--fs-caption);
  font-weight: var(--font-weight-medium);
  transition: all var(--transition-fast);
  cursor: pointer;
}

.btn--primary {
  background: var(--color-blue-dark);
  color: #fff;
  border: none;
}

.btn--primary:hover {
  background: var(--color-accent);
  color: #fff;
}

.btn--outline {
  background: transparent;
  color: var(--color-blue-dark);
  border: 1px solid var(--color-blue-dark);
}

.btn--outline:hover {
  background: var(--color-blue-dark);
  color: #fff;
}

.btn--large {
  padding: 14px 32px;
  font-size: var(--fs-body);
  border-radius: 28px;
}

/* --- Card (Generic) --- */
.card {
  background: var(--color-bg);
  border-radius: var(--radius-lg);
  overflow: hidden;
  box-shadow: var(--shadow-card);
}

/* --- Page Content Wrapper --- */
.page-content {
  margin-top: var(--nav-height);
  min-height: calc(100vh - var(--nav-height));
}

/* --- Responsive --- */
@media (max-width: 1024px) {
  .products-grid--3 {
    grid-template-columns: repeat(2, 1fr);
  }

  .features-grid {
    grid-template-columns: repeat(2, 1fr);
  }

  .product-hero {
    flex-direction: column;
    text-align: center;
  }

  .product-hero__image {
    max-width: 280px;
  }

  .about-certs {
    grid-template-columns: repeat(2, 1fr);
  }
}

@media (max-width: 768px) {
  .nav__links {
    display: none;
  }

  .nav__mobile-toggle {
    display: flex;
  }

  .products-grid--3,
  .products-grid--2 {
    grid-template-columns: 1fr;
  }

  .features-grid {
    grid-template-columns: 1fr;
  }

  .banner {
    height: 280px;
  }

  .banner__slide-title {
    font-size: 1.75rem;
  }

  .banner__arrow {
    display: none;
  }

  .footer__top {
    flex-direction: column;
    gap: var(--spacing-md);
  }

  .footer__bottom {
    flex-direction: column;
    text-align: center;
  }

  .about-hero {
    height: 240px;
  }

  .about-hero__title {
    font-size: 1.75rem;
  }

  .about-certs {
    grid-template-columns: repeat(2, 1fr);
  }

  .video-modal {
    padding: var(--spacing-sm);
  }

  .login-layout {
    flex-direction: column !important;
    padding: var(--spacing-lg) var(--spacing-sm) !important;
  }

  .login-layout__form {
    max-width: 100% !important;
    min-width: 0 !important;
  }

  .login-layout__guide {
    min-width: 0 !important;
    min-height: 300px;
  }
}

@media (max-width: 480px) {
  .banner {
    height: 240px;
  }

  .container {
    padding: 0 var(--spacing-sm);
  }

  .about-hero {
    height: 200px;
  }

  .about-hero__title {
    font-size: 1.3rem;
  }

  .about-hero__subtitle {
    font-size: 0.9375rem;
  }

  .about-hero__play-btn {
    padding: 12px 24px;
    font-size: var(--fs-caption);
  }

  .about-certs {
    grid-template-columns: 1fr;
    max-width: 300px;
    margin-left: auto;
    margin-right: auto;
  }

  .video-modal__container {
    border-radius: var(--radius-md);
  }

  /* Academy responsive */
  .academy-layout {
    flex-direction: column !important;
  }

  .academy-sidebar {
    width: 100% !important;
    flex-direction: row !important;
    overflow-x: auto;
    border-right: none !important;
    border-bottom: 1px solid var(--color-border-light);
    padding-bottom: var(--spacing-sm);
    border-radius: 0 !important;
  }

  .academy-sidebar__item {
    white-space: nowrap;
    padding: 8px 12px !important;
    font-size: var(--fs-small);
  }

  .academy-list-item {
    flex-direction: column;
    gap: var(--spacing-sm);
  }

  .academy-list-item__image {
    width: 100%;
    height: 160px;
  }
}

/* --- Login Page Layout (Left-Right) --- */
.login-layout {
  display: flex;
  min-height: calc(100vh - var(--nav-height));
  align-items: stretch;
}

.login-layout__form {
  flex: 1;
  padding: var(--spacing-2xl) var(--spacing-xl);
  display: flex;
  flex-direction: column;
  justify-content: center;
  align-items: center;
  background: var(--color-bg);
}

.login-layout__guide {
  flex: 1;
  background: linear-gradient(135deg, #e8f0fe 0%, #d4e4f7 50%, #c0d8f0 100%);
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  padding: var(--spacing-2xl);
  color: var(--color-text-primary);
}

.login-layout__guide-title {
  font-size: 1.75rem;
  font-weight: var(--font-weight-semibold);
  margin-bottom: 16px;
  text-align: center;
  color: var(--color-text-primary);
}

.login-layout__guide-text {
  font-size: 1.25rem;
  line-height: 1.8;
  color: var(--color-text-secondary);
  max-width: 400px;
  text-align: center;
}

.login-layout__guide-btn {
  margin-top: 32px;
}

/* --- Academy Layout (Sidebar + Waterfall) --- */
.academy-layout {
  display: flex;
  min-height: calc(100vh - var(--nav-height) - 100px);
}

.academy-sidebar {
  flex: 0 0 220px;
  background: var(--color-bg-tertiary);
  border-right: 1px solid var(--color-border-light);
  padding: var(--spacing-lg) var(--spacing-sm);
  border-radius: var(--radius-md) 0 0 var(--radius-md);
}

.academy-sidebar__title {
  font-size: var(--fs-body);
  color: var(--color-text-primary);
  padding: 0 var(--spacing-sm);
  margin-bottom: var(--spacing-md);
  font-weight: var(--font-weight-semibold);
}

.academy-sidebar__item {
  display: block;
  padding: 14px var(--spacing-sm);
  font-size: var(--fs-body);
  color: var(--color-text-primary);
  cursor: pointer;
  transition: all var(--transition-fast);
  text-decoration: none;
  border-left: 3px solid transparent;
  border-radius: var(--radius-sm);
  font-weight: var(--font-weight-medium);
}

.academy-sidebar__item:hover,
.academy-sidebar__item--active {
  color: var(--color-blue-dark);
  background: var(--color-blue-bg);
  border-left-color: var(--color-blue-dark);
}

.academy-content {
  flex: 1;
  padding: var(--spacing-lg) 0 var(--spacing-lg) var(--spacing-lg);
}

.academy-list {
  display: flex;
  flex-direction: column;
  gap: 0;
}

.academy-list-item {
  display: flex;
  gap: var(--spacing-lg);
  padding: var(--spacing-md) 0;
  border-bottom: 1px solid var(--color-border-light);
  cursor: pointer;
  transition: background var(--transition-fast);
}

.academy-list-item:last-child {
  border-bottom: none;
}

.academy-list-item:hover {
  background: var(--color-bg-secondary);
  border-radius: var(--radius-sm);
  margin: 0 calc(var(--spacing-sm) * -1);
  padding: var(--spacing-md) var(--spacing-sm);
}

.academy-list-item__image {
  flex-shrink: 0;
  width: 200px;
  height: 130px;
  background: var(--color-bg-secondary);
  border-radius: var(--radius-md);
  display: flex;
  align-items: center;
  justify-content: center;
  overflow: hidden;
  color: var(--color-text-tertiary);
  font-size: var(--fs-small);
}

.academy-list-item__image img {
  width: 100%;
  height: 100%;
  object-fit: cover;
}

.academy-list-item__body {
  flex: 1;
  display: flex;
  flex-direction: column;
  justify-content: center;
  min-width: 0;
}

.academy-list-item__title {
  font-size: var(--fs-body);
  font-weight: var(--font-weight-semibold);
  color: var(--color-text-primary);
  line-height: 1.5;
  margin-bottom: 6px;
}

.academy-list-item__meta {
  display: flex;
  gap: var(--spacing-sm);
  font-size: var(--fs-small);
  color: var(--color-text-tertiary);
  margin-bottom: 8px;
}

.academy-list-item__summary {
  font-size: var(--fs-small);
  color: var(--color-text-secondary);
  line-height: 1.6;
  display: -webkit-box;
  -webkit-line-clamp: 2;
  -webkit-box-orient: vertical;
  overflow: hidden;
}

/* --- About Page Hero (Full-width Image + Video) --- */
.about-hero {
  position: relative;
  width: 100%;
  height: 320px;
  margin-top: var(--nav-height);
  overflow: hidden;
  display: flex;
  align-items: center;
  justify-content: center;
}

.about-hero__bg {
  position: absolute;
  inset: 0;
  background: url('../img/about-hero-bg.jpg') center / cover no-repeat;
}

.about-hero__overlay {
  position: absolute;
  inset: 0;
  background: rgba(0, 0, 0, 0.25);
}

.about-hero__content {
  position: relative;
  z-index: 2;
  text-align: center;
  color: #fff;
}

.about-hero__title {
  font-size: clamp(2rem, 4vw, 3.3rem);
  font-weight: var(--font-weight-bold);
  letter-spacing: 0.08em;
  margin-bottom: 12px;
  text-shadow: 0 2px 30px rgba(0, 0, 0, 0.3);
}

.about-hero__subtitle {
  font-size: clamp(1rem, 2vw, 1.25rem);
  font-weight: var(--font-weight-regular);
  opacity: 0.92;
  margin-bottom: 36px;
  text-shadow: 0 1px 12px rgba(0, 0, 0, 0.3);
  letter-spacing: 0.04em;
}

.about-hero__play-btn {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  padding: 14px 32px;
  border-radius: 50px;
  background: rgba(255, 255, 255, 0.18);
  backdrop-filter: blur(10px);
  border: 1.5px solid rgba(255, 255, 255, 0.45);
  color: #fff;
  font-size: var(--fs-body);
  font-weight: var(--font-weight-medium);
  cursor: pointer;
  transition: all var(--transition-normal);
  letter-spacing: 0.02em;
}

.about-hero__play-btn:hover {
  background: rgba(255, 255, 255, 0.3);
  border-color: rgba(255, 255, 255, 0.7);
  transform: scale(1.03);
}

.about-hero__play-btn svg {
  margin-left: -2px;
}

/* --- Video Modal --- */
.video-modal {
  position: fixed;
  inset: 0;
  z-index: 2000;
  display: none;
  align-items: center;
  justify-content: center;
  padding: var(--spacing-xl);
}

.video-modal.is-open {
  display: flex;
}

.video-modal__backdrop {
  position: absolute;
  inset: 0;
  background: rgba(0, 0, 0, 0.75);
  backdrop-filter: blur(6px);
}

.video-modal__container {
  position: relative;
  z-index: 1;
  width: 100%;
  max-width: 900px;
  background: #000;
  border-radius: var(--radius-lg);
  overflow: hidden;
  box-shadow: 0 24px 80px rgba(0, 0, 0, 0.5);
}

.video-modal__close {
  position: absolute;
  top: -44px;
  right: 0;
  width: 36px;
  height: 36px;
  border-radius: 50%;
  background: rgba(255, 255, 255, 0.15);
  border: none;
  color: #fff;
  font-size: 22px;
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  transition: background var(--transition-fast);
  z-index: 2;
}

.video-modal__close:hover {
  background: rgba(255, 255, 255, 0.3);
}

.video-modal__player {
  width: 100%;
  aspect-ratio: 16/9;
}

.video-modal__player video {
  width: 100%;
  height: 100%;
  object-fit: contain;
  background: #000;
}

/* --- About Intro --- */
.about-intro {
  margin-top: var(--spacing-md);
  font-size: var(--fs-body);
  color: var(--color-text-secondary);
  line-height: 1.8;
  text-align: left;
}

/* --- About Innovation --- */
.about-innovation {
  margin-top: var(--spacing-md);
  font-size: var(--fs-body);
  color: var(--color-text-secondary);
  line-height: 1.8;
  text-align: center;
}

/* Innovation Timeline */
.about-innovation__timeline {
  max-width: 860px;
  margin: 0 auto;
  text-align: left;
}

.about-innovation__item {
  display: flex;
  align-items: flex-start;
  gap: 24px;
  padding: 20px 0;
  border-bottom: 1px solid var(--color-border-light);
}

.about-innovation__item:last-child {
  border-bottom: none;
}

.about-innovation__year {
  flex-shrink: 0;
  width: 72px;
  font-size: var(--fs-caption);
  font-weight: var(--font-weight-bold);
  color: var(--color-blue-dark);
  padding-top: 2px;
  letter-spacing: 0.02em;
}

.about-innovation__text {
  font-size: var(--fs-body);
  color: var(--color-text-secondary);
  line-height: 1.75;
  margin: 0;
}

/* --- About Certificate Cards --- */
.about-certs {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: var(--spacing-md);
  margin-top: var(--spacing-lg);
  margin-bottom: var(--spacing-xl);
}

.about-cert-card {
  text-align: center;
}

.about-cert-card__img {
  width: 100%;
  aspect-ratio: 1.414;
  background: var(--color-bg-secondary);
  border-radius: var(--radius-md);
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--color-text-tertiary);
  font-size: var(--fs-caption);
  overflow: hidden;
  border: 1px solid var(--color-border-light);
}

.about-cert-card__img img {
  width: 100%;
  height: 100%;
  object-fit: contain;
}

.about-cert-card__name {
  margin-top: 10px;
  font-size: var(--fs-caption);
  font-weight: var(--font-weight-medium);
  color: var(--color-text-primary);
  line-height: 1.4;
}

/* --- About Honor List --- */
.about-honor-list {
  max-width: 720px;
  margin: 0 auto;
}

.about-honor-item {
  display: flex;
  align-items: baseline;
  gap: 10px;
  padding: 14px 0;
  border-bottom: 1px solid var(--color-border-light);
}

.about-honor-item:last-child {
  border-bottom: none;
}

.about-honor-item__year {
  flex-shrink: 0;
  width: 48px;
  font-size: var(--fs-caption);
  font-weight: var(--font-weight-semibold);
  color: var(--color-blue-dark);
}

.about-honor-item__text {
  font-size: var(--fs-caption);
  color: var(--color-text-secondary);
  line-height: 1.5;
}

/* --- About Contact (Centered) --- */
.about-contact {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 20px;
  max-width: 600px;
  margin: var(--spacing-lg) auto 0;
  text-align: center;
}

.about-contact__item {
  display: flex;
  flex-direction: column;
  gap: 4px;
}

.about-contact__label {
  font-size: var(--fs-caption);
  color: var(--color-text-tertiary);
  font-weight: var(--font-weight-medium);
}

.about-contact__value {
  font-size: var(--fs-body);
  color: var(--color-text-primary);
  font-weight: var(--font-weight-medium);
}

/* --- Home Footer (qualifications only on homepage) --- */
.home-footer {
  background: var(--color-bg-secondary);
  border-top: 1px solid var(--color-border-light);
  padding: 30px 0 32px;
}

.home-footer__inner {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0 var(--spacing-md);
}

.home-footer__top {
  display: flex;
  justify-content: space-between;
  align-items: flex-start;
  margin-bottom: var(--spacing-lg);
  padding-bottom: var(--spacing-lg);
  border-bottom: 1px solid var(--color-border-light);
}

.home-footer__qualifications {
  display: flex;
  flex-direction: column;
  gap: 8px;
  flex: 1;
}

.home-footer__qual-link {
  font-size: var(--fs-small);
  color: var(--color-text-secondary);
  text-decoration: none;
  transition: color var(--transition-fast);
}

.home-footer__qual-link:hover {
  color: var(--color-text-primary);
}

.home-footer__social {
  flex-shrink: 0;
}

.home-footer__social-title {
  font-size: var(--fs-caption);
  font-weight: var(--font-weight-medium);
  color: var(--color-text-primary);
  margin-bottom: 12px;
}

.home-footer__social-links {
  display: flex;
  gap: 10px;
  align-items: center;
}

.home-footer__social-link {
  display: flex;
  align-items: center;
  gap: 4px;
  font-size: var(--fs-caption);
  color: var(--color-text-secondary);
  text-decoration: none;
  transition: color var(--transition-fast);
}

.home-footer__social-link:hover {
  color: var(--color-blue-dark);
}

.home-footer__social-logo {
  width: 32px;
  height: 32px;
  border-radius: 50%;
  object-fit: contain;
}

.home-footer__social-logo-placeholder {
  width: 32px;
  height: 32px;
  border-radius: 50%;
  background: var(--color-bg);
  display: inline-flex;
  align-items: center;
  justify-content: center;
  font-size: 10px;
  color: var(--color-text-tertiary);
  box-shadow: var(--shadow-sm);
}

.home-footer__bottom {
  display: flex;
  justify-content: space-between;
  align-items: center;
  flex-wrap: wrap;
  gap: var(--spacing-sm);
}

.home-footer__copyright {
  font-size: var(--fs-small);
  color: var(--color-text-tertiary);
}

.home-footer__links {
  display: flex;
  gap: 24px;
}

.home-footer__link {
  font-size: var(--fs-small);
  color: var(--color-text-tertiary);
  text-decoration: none;
}

.home-footer__link:hover {
  color: var(--color-text-primary);
}

/* --- Honors Badges (legacy, kept for other pages) --- */
.honors-grid {
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
  gap: var(--spacing-sm);
  margin-top: var(--spacing-lg);
}

.honor-badge {
  padding: 14px 28px;
  background: var(--color-bg-secondary);
  border-radius: var(--radius-sm);
  font-size: var(--fs-caption);
  color: var(--color-text-primary);
  font-weight: var(--font-weight-medium);
  border: 1px solid var(--color-border-light);
}

/* --- Privacy Policy Page --- */
.privacy-page {
  max-width: 800px;
  margin: 0 auto;
  padding: var(--spacing-xl) var(--spacing-md) var(--spacing-2xl);
}

.privacy-page__title {
  font-size: var(--fs-h1);
  font-weight: var(--font-weight-bold);
  color: var(--color-text-primary);
  text-align: center;
  margin-bottom: 8px;
  letter-spacing: -0.01em;
}

.privacy-page__update {
  font-size: var(--fs-caption);
  color: var(--color-text-tertiary);
  text-align: center;
  margin-bottom: var(--spacing-lg);
}

.privacy-page__section {
  margin-bottom: var(--spacing-lg);
}

.privacy-page__section p {
  font-size: var(--fs-caption);
  color: var(--color-text-secondary);
  line-height: 1.8;
  margin-bottom: 14px;
}

.privacy-page__highlight {
  font-size: var(--fs-caption) !important;
  font-weight: var(--font-weight-medium) !important;
  color: var(--color-text-primary) !important;
  padding: 14px 18px;
  background: var(--color-bg-secondary);
  border-radius: var(--radius-sm);
  border-left: 3px solid var(--color-blue-dark);
  margin-bottom: 14px !important;
}

.privacy-page__toc {
  counter-reset: toc-counter;
  list-style: none;
  padding-left: 0;
  margin-top: 12px;
}

.privacy-page__toc li {
  counter-increment: toc-counter;
  padding: 10px 0;
  font-size: var(--fs-caption);
  color: var(--color-text-secondary);
  border-bottom: 1px solid var(--color-border-light);
  display: flex;
  align-items: center;
  gap: 8px;
}

.privacy-page__toc li::before {
  content: counter(toc-counter) ".";
  font-weight: var(--font-weight-semibold);
  color: var(--color-blue-dark);
  flex-shrink: 0;
}

.privacy-page__heading {
  font-size: var(--fs-h3);
  font-weight: var(--font-weight-bold);
  color: var(--color-text-primary);
  margin-top: var(--spacing-xl);
  margin-bottom: var(--spacing-md);
  padding-top: var(--spacing-sm);
  letter-spacing: -0.01em;
}

.privacy-page__subheading {
  font-size: var(--fs-h4);
  font-weight: var(--font-weight-semibold);
  color: var(--color-text-primary);
  margin-top: var(--spacing-lg);
  margin-bottom: var(--spacing-sm);
}

.privacy-page__subheading2 {
  font-size: var(--fs-body);
  font-weight: var(--font-weight-semibold);
  color: var(--color-text-primary);
  margin-top: var(--spacing-md);
  margin-bottom: var(--spacing-sm);
}

.privacy-page p {
  font-size: var(--fs-caption);
  color: var(--color-text-secondary);
  line-height: 1.8;
  margin-bottom: 14px;
}

.privacy-page__list {
  list-style: none;
  padding-left: 0;
  margin-bottom: 14px;
}

.privacy-page__list li {
  font-size: var(--fs-caption);
  color: var(--color-text-secondary);
  line-height: 1.8;
  padding: 6px 0 6px 20px;
  position: relative;
}

.privacy-page__list li::before {
  content: "•";
  position: absolute;
  left: 4px;
  color: var(--color-text-tertiary);
}

.privacy-page__list ol {
  list-style: decimal;
  padding-left: 24px;
}

@media (max-width: 768px) {
  .privacy-page {
    padding: var(--spacing-lg) var(--spacing-sm) var(--spacing-xl);
  }

  .privacy-page__heading {
    font-size: var(--fs-h4);
  }
}