@charset "UTF-8";

/* ==========================================================================
   Modern Minimalist Enterprise Theme - Base Variables (Matching main.css)
   ========================================================================== */
:root {
  /* Color Palette */
  --color-primary: #0066cc;
  --color-primary-hover: #004499;
  --color-text-main: #1d1d1f;
  --color-text-secondary: #86868b;
  --color-text-muted: #a1a1a6;
  --color-bg-body: #ffffff;
  --color-bg-body: #f5f5f7;
  --color-bg-card: #ffffff;
  --color-border: #d2d2d7;

  /* Gradients */
  --gradient-primary: linear-gradient(135deg, #0071e3 0%, #43b9ff 100%);
  --gradient-banner: linear-gradient(135deg, #f5f5f7 0%, #e8e8ed 100%);

  /* Typography */
  --font-family-base: system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", "PingFang SC", "Microsoft YaHei", sans-serif;

  /* Layout & Spacing */
  --max-width-container: 1200px;
  --header-height: 64px;

  /* Shadows */
  --shadow-sm: 0 2px 8px rgba(0, 0, 0, 0.04);
  --shadow-md: 0 4px 16px rgba(0, 0, 0, 0.06);
  --shadow-lg: 0 12px 32px rgba(0, 0, 0, 0.08);
  --shadow-hover: 0 20px 48px rgba(0, 0, 0, 0.12);

  /* Transitions */
  --transition-base: all 0.4s cubic-bezier(0.16, 1, 0.3, 1);
}

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

body {
  font-family: var(--font-family-base);
  background-color: var(--color-bg-body);
  color: var(--color-text-main);
  line-height: 1.5;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  overflow-x: hidden;
}

a {
  text-decoration: none;
  color: inherit;
  transition: var(--transition-base);
}

ul {
  list-style: none;
}

/* ==========================================================================
   Header & Navigation
   ========================================================================== */
header {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: var(--header-height);
  background: rgba(255, 255, 255, 0.85);
  backdrop-filter: saturate(180%) blur(20px);
  -webkit-backdrop-filter: saturate(180%) blur(20px);
  border-bottom: 1px solid rgba(0, 0, 0, 0.08);
  z-index: 1000;
  transition: background-color 0.3s ease;
}

.nav-container {
  max-width: var(--max-width-container);
  height: 100%;
  margin: 0 auto;
  padding: 0 24px;
  display: flex;
  justify-content: space-between;
  align-items: center;
}

.logo {
  display: flex;
  align-items: center;
  gap: 12px;
  font-size: 20px;
  font-weight: 600;
  color: var(--color-text-main);
  letter-spacing: -0.5px;
}

.logo-img {
  width: 32px;
  height: 32px;
  object-fit: contain;
}

.nav-menu {
  display: flex;
  gap: 36px;
}

.nav-menu a {
  font-size: 14px;
  color: var(--color-text-main);
  font-weight: 500;
  opacity: 0.8;
  position: relative;
}

.nav-menu a:hover {
  opacity: 1;
  color: var(--color-primary);
}

.nav-menu a.action {
  opacity: 1;
  color: var(--color-primary);
}

.menu-toggle {
  display: none;
  font-size: 24px;
  cursor: pointer;
  color: var(--color-text-main);
}

/* ==========================================================================
   Page Banner Small
   ========================================================================== */
@keyframes bgPulse {
  0% {
    transform: scale(1);
    opacity: 0.5;
  }

  50% {
    transform: scale(1.5);
    opacity: 0.8;
  }

  100% {
    transform: scale(1);
    opacity: 0.5;
  }
}

.page-banner-small {
  margin-top: var(--header-height);
  height: 220px;
  background: var(--color-bg-body);
  display: flex;
  align-items: center;
  justify-content: center;
  text-align: center;
  padding: 0 24px;
  position: relative;
  overflow: hidden;
}


.page-banner-content {
  position: relative;
  z-index: 2;
  animation: fadeUp 0.8s cubic-bezier(0.16, 1, 0.3, 1) forwards;
}

.page-banner-content h1 {
  font-size: 40px;
  font-weight: 700;
  color: var(--color-text-main);
  margin-bottom: 12px;
  letter-spacing: -1px;
}

.page-banner-content p {
  font-size: 18px;
  color: var(--color-text-secondary);
  font-weight: 400;
}

/* ==========================================================================
   Product Detail Container
   ========================================================================== */
.container {
  max-width: var(--max-width-container);
  margin: 0 auto;
  padding: 0 24px;
}

.breadcrumb {
  margin: 32px 0;
  color: var(--color-text-muted);
  font-size: 14px;
}

.breadcrumb a {
  color: var(--color-text-secondary);
  transition: var(--transition-base);
}

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

/* ==========================================================================
   Product Layout
   ========================================================================== */
.product-detail {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 60px;
  margin: 40px 0 80px;
  align-items: start;
}

.product-gallery {
  background: var(--color-bg-card);
  border-radius: 24px;
  overflow: hidden;
  border: 1px solid var(--color-border);
  box-shadow: var(--shadow-sm);
  transition: var(--transition-base);
  animation: fadeUp 0.8s cubic-bezier(0.16, 1, 0.3, 1) forwards;
}

.product-gallery:hover {
  box-shadow: var(--shadow-md);
}

.product-main-img {
  height: 360px;
  background: var(--color-bg-body);
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--color-primary);
  font-size: 32px;
  font-weight: 700;
  letter-spacing: 1px;
  border-bottom: 1px solid var(--color-border);
}

.product-thumbs {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  padding: 24px;
  background: var(--color-bg-body);
}

.thumb {
  flex: 1 1 calc(25% - 12px);
  min-width: 80px;
  height: 60px;
  background: var(--color-bg-body);
  border: 1px solid var(--color-border);
  border-radius: 12px;
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--color-text-secondary);
  font-size: 13px;
  font-weight: 500;
  cursor: default;
  transition: var(--transition-base);
}

.thumb:hover {
  border-color: var(--color-primary);
  color: var(--color-primary);
  background: var(--color-bg-body);
}

.product-info {
  background: transparent;
  animation: fadeUp 1s cubic-bezier(0.16, 1, 0.3, 1) forwards;
}

.product-category {
  color: var(--color-primary);
  font-weight: 600;
  font-size: 12px;
  text-transform: uppercase;
  letter-spacing: 1px;
  margin-bottom: 16px;
  display: inline-block;
  padding: 6px 16px;
  background: rgba(0, 102, 204, 0.1);
  border-radius: 20px;
}

.product-info h2 {
  font-size: 36px;
  color: var(--color-text-main);
  margin-bottom: 32px;
  font-weight: 700;
  letter-spacing: -1px;
}

.product-price-box {
  background: var(--color-bg-body);
  padding: 24px 32px;
  border-radius: 20px;
  margin-bottom: 32px;
}

.price-label {
  font-size: 14px;
  color: var(--color-text-secondary);
  margin-bottom: 8px;
}

.product-price {
  font-size: 40px;
  color: var(--color-text-main);
  font-weight: 800;
  letter-spacing: -1px;
  display: flex;
  align-items: baseline;
  gap: 8px;
}

.product-desc {
  margin-bottom: 32px;
}

.product-desc h4 {
  font-size: 18px;
  color: var(--color-text-main);
  margin-bottom: 12px;
  font-weight: 600;
}

.product-desc p {
  color: var(--color-text-secondary);
  line-height: 1.6;
  font-size: 15px;
}

.product-meta {
  border-top: 1px solid var(--color-border);
  border-bottom: 1px solid var(--color-border);
  padding: 24px 0;
  margin-bottom: 32px;
}

.meta-item {
  display: flex;
  align-items: flex-start;
  gap: 24px;
  margin-bottom: 16px;
}

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

.meta-label {
  min-width: 80px;
  color: var(--color-text-muted);
  font-size: 14px;
  font-weight: 500;
}

.meta-value {
  color: var(--color-text-main);
  font-size: 14px;
  line-height: 1.6;
}

.product-actions {
  display: flex;
  gap: 16px;
}

.btn-signup {
  width: 100%;
  background: var(--color-primary);
  color: #fff;
  border: none;
  padding: 18px 40px;
  border-radius: 30px;
  font-size: 16px;
  font-weight: 600;
  cursor: pointer;
  transition: var(--transition-base);
  box-shadow: var(--shadow-sm);
}

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

/* ==========================================================================
   Course Features & Teacher Section
   ========================================================================== */
.section-title {
  margin-bottom: 40px;
}

.section-title h2 {
  font-size: 28px;
  color: var(--color-text-main);
  font-weight: 700;
  letter-spacing: -0.5px;
}

.course-features {
  padding: 80px 0;
  margin: 80px 0;
  border-top: 1px solid var(--color-border);
  animation: fadeUp 1.2s cubic-bezier(0.16, 1, 0.3, 1) forwards;
}

.features-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  gap: 40px;
}

.feature-item {
  padding: 40px 32px;
  background: transparent;
  border-radius: 24px;
  transition: var(--transition-base);
  text-align: left;
  border: 1px solid transparent;
}

.feature-item:hover {
  transform: translateY(-8px);
  background: var(--color-bg-card);
  box-shadow: var(--shadow-lg);
  border-color: rgba(0, 102, 204, 0.1);
}

.feature-icon {
  font-size: 48px;
  margin-bottom: 24px;
  background: var(--gradient-primary);
  -webkit-background-clip: text;
  background-clip: text;
  -webkit-text-fill-color: transparent;
  display: inline-block;
}

.feature-item h4 {
  font-size: 22px;
  color: var(--color-text-main);
  margin-bottom: 16px;
  font-weight: 700;
  letter-spacing: -0.5px;
}

.feature-item p {
  color: var(--color-text-secondary);
  font-size: 16px;
  line-height: 1.7;
}

/* ==========================================================================
   Course Syllabus
   ========================================================================== */
.course-syllabus {
  margin: 80px 0;
  animation: fadeUp 1.2s cubic-bezier(0.16, 1, 0.3, 1) forwards;
}

.syllabus-list {
  display: flex;
  flex-direction: column;
  gap: 16px;
  max-width: 860px;
  margin: 0 auto;
}

.syllabus-item {
  background: var(--color-bg-card);
  border: 1px solid var(--color-border);
  border-radius: 16px;
  padding: 24px 32px;
  transition: var(--transition-base);
  position: relative;
  overflow: hidden;
}

.syllabus-item:hover {
  box-shadow: var(--shadow-md);
  border-color: rgba(0, 102, 204, 0.3);
  transform: translateY(-2px);
}

.syllabus-item::before {
  content: "";
  position: absolute;
  left: 0;
  top: 0;
  bottom: 0;
  width: 4px;
  background: var(--color-primary);
  opacity: 0;
  transition: var(--transition-base);
}

.syllabus-item:hover::before {
  opacity: 1;
}

.syllabus-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 12px;
}

.syllabus-title {
  font-size: 20px;
  font-weight: 600;
  color: var(--color-text-main);
  display: flex;
  align-items: center;
  gap: 12px;
}

.syllabus-tag {
  background: rgba(0, 102, 204, 0.1);
  color: var(--color-primary);
  font-size: 13px;
  padding: 4px 10px;
  border-radius: 6px;
  font-weight: 500;
}

.syllabus-desc {
  color: var(--color-text-secondary);
  font-size: 15px;
  line-height: 1.6;
}

.teacher-section {
  background: var(--color-bg-card);
  border-radius: 24px;
  padding: 60px 48px;
  margin: 80px 0;
  border: 1px solid var(--color-border);
  box-shadow: var(--shadow-sm);
  animation: fadeUp 1.4s cubic-bezier(0.16, 1, 0.3, 1) forwards;
}

.teacher-info {
  display: flex;
  gap: 48px;
  align-items: center;
}

.teacher-avatar {
  width: 120px;
  height: 120px;
  flex-shrink: 0;
  background: var(--color-bg-body);
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 56px;
  border: 1px solid var(--color-border);
}

.teacher-desc h3 {
  font-size: 24px;
  color: var(--color-text-main);
  margin-bottom: 8px;
  font-weight: 700;
}

.teacher-title {
  color: var(--color-primary);
  font-weight: 600;
  margin-bottom: 16px;
  font-size: 15px;
}

.teacher-desc p {
  color: var(--color-text-secondary);
  line-height: 1.6;
  font-size: 15px;
}

/* ==========================================================================
   Animations & Responsive
   ========================================================================== */
@keyframes fadeUp {
  0% {
    opacity: 0;
    transform: translateY(20px);
  }

  100% {
    opacity: 1;
    transform: translateY(0);
  }
}

@media (max-width: 992px) {
  .product-detail {
    grid-template-columns: 1fr;
    gap: 40px;
  }
}

@media (max-width: 768px) {
  .menu-toggle {
    display: block;
  }

  .nav-menu {
    position: fixed;
    top: var(--header-height);
    left: -100%;
    width: 100%;
    height: calc(100vh - var(--header-height));
    background: var(--color-bg-body);
    flex-direction: column;
    padding: 40px 24px;
    transition: var(--transition-base);
  }

  .nav-menu.active {
    left: 0;
  }

  .nav-menu a {
    font-size: 20px;
    display: block;
    padding: 12px 0;
  }

  .page-banner-small {
    height: 180px;
  }

  .page-banner-content h1 {
    font-size: 32px;
  }

  .course-features,
  .teacher-section {
    padding: 32px 24px;
  }

  .teacher-info {
    flex-direction: column;
    text-align: center;
    gap: 24px;
  }

  .copyright {
    flex-direction: column;
    gap: 16px;
    text-align: center;
  }
}

::-webkit-scrollbar {
  width: 8px;
}

::-webkit-scrollbar-track {
  background: var(--color-bg-body);
}

::-webkit-scrollbar-thumb {
  background: var(--color-border);
  border-radius: 4px;
}

::-webkit-scrollbar-thumb:hover {
  background: var(--color-text-muted);
}

::selection {
  background: var(--color-primary);
  color: #fff;
}