/* ===================================================
   蘑菇视频 - 主样式表
   Modern Minimal High-end Design
   =================================================== */

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

:root {
  --color-bg: #fafaf8;
  --color-surface: #ffffff;
  --color-text: #1a1a1a;
  --color-text-muted: #6b6b6b;
  --color-text-light: #9a9a9a;
  --color-accent: #2d6a4f;
  --color-accent-light: #52b788;
  --color-accent-pale: #f0f7f4;
  --color-border: #e8e8e4;
  --color-border-light: #f0f0ec;
  --font-sans: 'PingFang SC', 'Hiragino Sans GB', 'Microsoft YaHei', 'Noto Sans SC', sans-serif;
  --font-display: 'PingFang SC', 'Hiragino Sans GB', 'Microsoft YaHei', sans-serif;
  --radius-sm: 6px;
  --radius-md: 12px;
  --radius-lg: 20px;
  --radius-xl: 32px;
  --shadow-sm: 0 1px 4px rgba(0,0,0,0.06);
  --shadow-md: 0 4px 20px rgba(0,0,0,0.08);
  --shadow-lg: 0 12px 40px rgba(0,0,0,0.10);
  --transition: 0.3s cubic-bezier(0.4,0,0.2,1);
}

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

body {
  font-family: var(--font-sans);
  background: var(--color-bg);
  color: var(--color-text);
  line-height: 1.7;
  -webkit-font-smoothing: antialiased;
}

a { color: inherit; text-decoration: none; transition: color var(--transition); }
img { max-width: 100%; height: auto; display: block; }
ul { list-style: none; }
button { cursor: pointer; border: none; background: none; font-family: inherit; }

/* ===================================================
   Layout
   =================================================== */
.container {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 24px;
}

.section {
  padding: 96px 0;
}

.section--sm {
  padding: 64px 0;
}

/* ===================================================
   Header & Navigation
   =================================================== */
.site-header {
  position: sticky;
  top: 0;
  z-index: 100;
  background: rgba(250,250,248,0.92);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--color-border-light);
  transition: box-shadow var(--transition);
}

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

.header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 68px;
  gap: 24px;
}

.site-logo {
  display: flex;
  align-items: center;
  gap: 10px;
  font-size: 1.2rem;
  font-weight: 700;
  color: var(--color-text);
  white-space: nowrap;
  flex-shrink: 0;
}

.logo-icon {
  width: 36px;
  height: 36px;
  background: var(--color-accent);
  border-radius: 10px;
  display: flex;
  align-items: center;
  justify-content: center;
  color: #fff;
  font-size: 1rem;
}

.site-nav {
  display: flex;
  align-items: center;
  gap: 4px;
}

.site-nav a {
  padding: 6px 14px;
  border-radius: var(--radius-sm);
  font-size: 0.9rem;
  color: var(--color-text-muted);
  transition: all var(--transition);
}

.site-nav a:hover,
.site-nav a.active {
  color: var(--color-text);
  background: var(--color-accent-pale);
}

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

.btn {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 9px 22px;
  border-radius: var(--radius-sm);
  font-size: 0.875rem;
  font-weight: 500;
  transition: all var(--transition);
  white-space: nowrap;
}

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

.btn-primary:hover {
  background: #245a42;
  transform: translateY(-1px);
  box-shadow: 0 4px 12px rgba(45,106,79,0.3);
}

.btn-outline {
  border: 1.5px solid var(--color-border);
  color: var(--color-text-muted);
}

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

/* Mobile menu toggle */
.menu-toggle {
  display: none;
  flex-direction: column;
  gap: 5px;
  padding: 8px;
  border-radius: var(--radius-sm);
}

.menu-toggle span {
  display: block;
  width: 22px;
  height: 2px;
  background: var(--color-text);
  transition: all var(--transition);
}

/* ===================================================
   Search Bar
   =================================================== */
.search-bar-wrap {
  background: var(--color-surface);
  border-bottom: 1px solid var(--color-border-light);
  padding: 12px 0;
}

.search-bar-inner {
  display: flex;
  align-items: center;
  gap: 12px;
  max-width: 680px;
  margin: 0 auto;
  padding: 0 24px;
}

.search-input-wrap {
  position: relative;
  flex: 1;
}

.search-input-wrap svg {
  position: absolute;
  left: 14px;
  top: 50%;
  transform: translateY(-50%);
  color: var(--color-text-light);
  pointer-events: none;
}

.search-input {
  width: 100%;
  padding: 10px 14px 10px 42px;
  border: 1.5px solid var(--color-border);
  border-radius: var(--radius-md);
  font-size: 0.9rem;
  font-family: var(--font-sans);
  background: var(--color-bg);
  color: var(--color-text);
  transition: border-color var(--transition), box-shadow var(--transition);
  outline: none;
}

.search-input:focus {
  border-color: var(--color-accent-light);
  box-shadow: 0 0 0 3px rgba(82,183,136,0.12);
}

.search-btn {
  padding: 10px 22px;
  background: var(--color-accent);
  color: #fff;
  border-radius: var(--radius-md);
  font-size: 0.875rem;
  font-weight: 500;
  transition: all var(--transition);
}

.search-btn:hover {
  background: #245a42;
}

/* ===================================================
   Hero Banner
   =================================================== */
.hero {
  position: relative;
  min-height: 580px;
  display: flex;
  align-items: center;
  overflow: hidden;
  background: linear-gradient(135deg, #1a2e24 0%, #2d6a4f 60%, #52b788 100%);
}

.hero-bg {
  position: absolute;
  inset: 0;
  background-image: url('../images/hero_banner.jpg');
  background-size: cover;
  background-position: center;
  opacity: 0.18;
}

.hero-content {
  position: relative;
  z-index: 2;
  max-width: 680px;
  padding: 80px 0;
}

.hero-eyebrow {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  background: rgba(255,255,255,0.12);
  border: 1px solid rgba(255,255,255,0.2);
  padding: 6px 16px;
  border-radius: 100px;
  font-size: 0.8rem;
  color: rgba(255,255,255,0.85);
  margin-bottom: 28px;
  backdrop-filter: blur(8px);
}

.hero h1 {
  font-size: clamp(2.4rem, 5vw, 3.8rem);
  font-weight: 800;
  color: #fff;
  line-height: 1.15;
  margin-bottom: 20px;
  letter-spacing: -0.02em;
}

.hero h1 span {
  color: #95d5b2;
}

.hero-desc {
  font-size: 1.1rem;
  color: rgba(255,255,255,0.78);
  margin-bottom: 40px;
  line-height: 1.8;
}

.hero-actions {
  display: flex;
  gap: 14px;
  flex-wrap: wrap;
}

.btn-hero-primary {
  padding: 14px 32px;
  background: #fff;
  color: var(--color-accent);
  border-radius: var(--radius-md);
  font-size: 1rem;
  font-weight: 600;
  transition: all var(--transition);
}

.btn-hero-primary:hover {
  transform: translateY(-2px);
  box-shadow: 0 8px 24px rgba(0,0,0,0.2);
}

.btn-hero-outline {
  padding: 14px 32px;
  border: 1.5px solid rgba(255,255,255,0.4);
  color: #fff;
  border-radius: var(--radius-md);
  font-size: 1rem;
  font-weight: 500;
  transition: all var(--transition);
  backdrop-filter: blur(4px);
}

.btn-hero-outline:hover {
  background: rgba(255,255,255,0.1);
  border-color: rgba(255,255,255,0.7);
}

.hero-stats {
  display: flex;
  gap: 40px;
  margin-top: 56px;
  padding-top: 40px;
  border-top: 1px solid rgba(255,255,255,0.15);
}

.hero-stat-item {
  text-align: left;
}

.hero-stat-num {
  font-size: 1.8rem;
  font-weight: 800;
  color: #fff;
  line-height: 1;
  margin-bottom: 4px;
}

.hero-stat-label {
  font-size: 0.8rem;
  color: rgba(255,255,255,0.6);
}

/* ===================================================
   Section Headings
   =================================================== */
.section-heading {
  text-align: center;
  margin-bottom: 60px;
}

.section-heading .eyebrow {
  display: inline-block;
  font-size: 0.75rem;
  font-weight: 600;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--color-accent);
  margin-bottom: 12px;
}

.section-heading h2 {
  font-size: clamp(1.8rem, 3vw, 2.6rem);
  font-weight: 700;
  color: var(--color-text);
  line-height: 1.25;
  margin-bottom: 16px;
  letter-spacing: -0.02em;
}

.section-heading p {
  font-size: 1rem;
  color: var(--color-text-muted);
  max-width: 520px;
  margin: 0 auto;
}

/* ===================================================
   Video Cards
   =================================================== */
.video-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
  gap: 28px;
}

.video-card {
  background: var(--color-surface);
  border-radius: var(--radius-lg);
  overflow: hidden;
  border: 1px solid var(--color-border-light);
  transition: all var(--transition);
  cursor: pointer;
}

.video-card:hover {
  transform: translateY(-6px);
  box-shadow: var(--shadow-lg);
  border-color: transparent;
}

.video-thumb {
  position: relative;
  aspect-ratio: 16/9;
  overflow: hidden;
  background: #e8e8e4;
}

.video-thumb img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  transition: transform 0.5s cubic-bezier(0.4,0,0.2,1);
}

.video-card:hover .video-thumb img {
  transform: scale(1.06);
}

.video-play-btn {
  position: absolute;
  inset: 0;
  display: flex;
  align-items: center;
  justify-content: center;
  background: rgba(0,0,0,0);
  transition: background var(--transition);
  opacity: 0;
}

.video-card:hover .video-play-btn {
  opacity: 1;
  background: rgba(0,0,0,0.35);
}

.play-circle {
  width: 56px;
  height: 56px;
  background: rgba(255,255,255,0.95);
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  transform: scale(0.8);
  transition: transform var(--transition);
}

.video-card:hover .play-circle {
  transform: scale(1);
}

.play-circle svg {
  color: var(--color-accent);
  margin-left: 3px;
}

.video-duration {
  position: absolute;
  bottom: 10px;
  right: 10px;
  background: rgba(0,0,0,0.7);
  color: #fff;
  font-size: 0.75rem;
  padding: 3px 8px;
  border-radius: 4px;
}

.video-body {
  padding: 18px 20px 20px;
}

.video-tags {
  display: flex;
  gap: 6px;
  flex-wrap: wrap;
  margin-bottom: 10px;
}

.tag {
  font-size: 0.72rem;
  padding: 3px 10px;
  background: var(--color-accent-pale);
  color: var(--color-accent);
  border-radius: 100px;
  font-weight: 500;
}

.video-title {
  font-size: 0.95rem;
  font-weight: 600;
  color: var(--color-text);
  line-height: 1.5;
  margin-bottom: 12px;
  display: -webkit-box;
  -webkit-line-clamp: 2;
  -webkit-box-orient: vertical;
  overflow: hidden;
}

.video-meta {
  display: flex;
  align-items: center;
  justify-content: space-between;
  font-size: 0.8rem;
  color: var(--color-text-light);
}

.video-author {
  display: flex;
  align-items: center;
  gap: 6px;
}

.author-avatar {
  width: 22px;
  height: 22px;
  border-radius: 50%;
  background: var(--color-accent-pale);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 0.65rem;
  color: var(--color-accent);
  font-weight: 600;
}

.video-stats {
  display: flex;
  gap: 12px;
}

.video-stat {
  display: flex;
  align-items: center;
  gap: 3px;
}

/* ===================================================
   Board Categories
   =================================================== */
.boards-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(260px, 1fr));
  gap: 24px;
}

.board-card {
  background: var(--color-surface);
  border: 1px solid var(--color-border-light);
  border-radius: var(--radius-lg);
  padding: 32px 28px;
  transition: all var(--transition);
  position: relative;
  overflow: hidden;
}

.board-card::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 3px;
  background: var(--color-accent);
  transform: scaleX(0);
  transform-origin: left;
  transition: transform var(--transition);
}

.board-card:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-md);
  border-color: transparent;
}

.board-card:hover::before {
  transform: scaleX(1);
}

.board-icon {
  width: 52px;
  height: 52px;
  background: var(--color-accent-pale);
  border-radius: var(--radius-md);
  display: flex;
  align-items: center;
  justify-content: center;
  margin-bottom: 20px;
  color: var(--color-accent);
  font-size: 1.4rem;
}

.board-name {
  font-size: 1.05rem;
  font-weight: 700;
  color: var(--color-text);
  margin-bottom: 8px;
}

.board-desc {
  font-size: 0.875rem;
  color: var(--color-text-muted);
  line-height: 1.6;
  margin-bottom: 20px;
}

.board-meta {
  display: flex;
  gap: 16px;
  font-size: 0.8rem;
  color: var(--color-text-light);
}

/* ===================================================
   Stats Section
   =================================================== */
.stats-section {
  background: var(--color-text);
  padding: 80px 0;
}

.stats-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(180px, 1fr));
  gap: 40px;
  text-align: center;
}

.stat-item .num {
  font-size: 3rem;
  font-weight: 800;
  color: #fff;
  line-height: 1;
  margin-bottom: 8px;
  letter-spacing: -0.03em;
}

.stat-item .num span {
  color: var(--color-accent-light);
}

.stat-item .label {
  font-size: 0.875rem;
  color: rgba(255,255,255,0.55);
}

/* ===================================================
   Testimonials
   =================================================== */
.testimonials-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
  gap: 24px;
}

.testimonial-card {
  background: var(--color-surface);
  border: 1px solid var(--color-border-light);
  border-radius: var(--radius-lg);
  padding: 28px;
  transition: all var(--transition);
}

.testimonial-card:hover {
  box-shadow: var(--shadow-md);
  transform: translateY(-3px);
}

.testimonial-stars {
  display: flex;
  gap: 3px;
  margin-bottom: 16px;
  color: #f5a623;
  font-size: 0.9rem;
}

.testimonial-text {
  font-size: 0.9rem;
  color: var(--color-text-muted);
  line-height: 1.7;
  margin-bottom: 20px;
}

.testimonial-author {
  display: flex;
  align-items: center;
  gap: 12px;
}

.testimonial-avatar {
  width: 40px;
  height: 40px;
  border-radius: 50%;
  background: var(--color-accent-pale);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 0.9rem;
  font-weight: 700;
  color: var(--color-accent);
}

.testimonial-name {
  font-size: 0.875rem;
  font-weight: 600;
  color: var(--color-text);
}

.testimonial-role {
  font-size: 0.78rem;
  color: var(--color-text-light);
}

/* ===================================================
   FAQ
   =================================================== */
.faq-list {
  max-width: 780px;
  margin: 0 auto;
}

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

.faq-question {
  width: 100%;
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 22px 0;
  font-size: 0.95rem;
  font-weight: 600;
  color: var(--color-text);
  text-align: left;
  gap: 16px;
  transition: color var(--transition);
}

.faq-question:hover {
  color: var(--color-accent);
}

.faq-icon {
  width: 28px;
  height: 28px;
  border-radius: 50%;
  border: 1.5px solid var(--color-border);
  display: flex;
  align-items: center;
  justify-content: center;
  flex-shrink: 0;
  transition: all var(--transition);
  font-size: 1rem;
  color: var(--color-text-muted);
}

.faq-item.open .faq-icon {
  background: var(--color-accent);
  border-color: var(--color-accent);
  color: #fff;
  transform: rotate(45deg);
}

.faq-answer {
  display: none;
  padding: 0 0 22px;
  font-size: 0.9rem;
  color: var(--color-text-muted);
  line-height: 1.8;
}

.faq-item.open .faq-answer {
  display: block;
}

/* ===================================================
   Contact / Join Section
   =================================================== */
.join-section {
  background: var(--color-accent-pale);
  border-radius: var(--radius-xl);
  padding: 72px 60px;
  text-align: center;
  margin: 0 24px;
}

.join-section h2 {
  font-size: clamp(1.8rem, 3vw, 2.4rem);
  font-weight: 700;
  color: var(--color-text);
  margin-bottom: 16px;
}

.join-section p {
  font-size: 1rem;
  color: var(--color-text-muted);
  margin-bottom: 36px;
  max-width: 480px;
  margin-left: auto;
  margin-right: auto;
}

.join-form {
  display: flex;
  gap: 12px;
  max-width: 480px;
  margin: 0 auto;
}

.join-input {
  flex: 1;
  padding: 13px 18px;
  border: 1.5px solid var(--color-border);
  border-radius: var(--radius-md);
  font-size: 0.9rem;
  font-family: var(--font-sans);
  background: #fff;
  outline: none;
  transition: border-color var(--transition);
}

.join-input:focus {
  border-color: var(--color-accent-light);
}

/* ===================================================
   Footer
   =================================================== */
.site-footer {
  background: var(--color-text);
  color: rgba(255,255,255,0.7);
  padding: 64px 0 32px;
}

.footer-top {
  display: grid;
  grid-template-columns: 1.5fr repeat(3, 1fr);
  gap: 48px;
  margin-bottom: 48px;
}

.footer-brand .site-logo {
  color: #fff;
  margin-bottom: 16px;
}

.footer-brand p {
  font-size: 0.875rem;
  line-height: 1.7;
  color: rgba(255,255,255,0.5);
  max-width: 260px;
}

.footer-col h4 {
  font-size: 0.875rem;
  font-weight: 600;
  color: #fff;
  margin-bottom: 16px;
}

.footer-col ul li {
  margin-bottom: 10px;
}

.footer-col ul li a {
  font-size: 0.85rem;
  color: rgba(255,255,255,0.5);
  transition: color var(--transition);
}

.footer-col ul li a:hover {
  color: var(--color-accent-light);
}

.footer-bottom {
  border-top: 1px solid rgba(255,255,255,0.08);
  padding-top: 28px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 12px;
}

.footer-bottom p {
  font-size: 0.8rem;
  color: rgba(255,255,255,0.35);
}

.footer-social {
  display: flex;
  gap: 12px;
}

.social-link {
  width: 34px;
  height: 34px;
  border-radius: 50%;
  border: 1px solid rgba(255,255,255,0.15);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 0.75rem;
  color: rgba(255,255,255,0.5);
  transition: all var(--transition);
}

.social-link:hover {
  background: var(--color-accent);
  border-color: var(--color-accent);
  color: #fff;
}

/* ===================================================
   Page Hero (Inner Pages)
   =================================================== */
.page-hero {
  background: linear-gradient(135deg, #1a2e24 0%, #2d6a4f 100%);
  padding: 80px 0;
  text-align: center;
}

.page-hero h1 {
  font-size: clamp(2rem, 4vw, 3rem);
  font-weight: 800;
  color: #fff;
  margin-bottom: 16px;
  letter-spacing: -0.02em;
}

.page-hero p {
  font-size: 1.05rem;
  color: rgba(255,255,255,0.7);
  max-width: 520px;
  margin: 0 auto;
}

/* ===================================================
   Breadcrumb
   =================================================== */
.breadcrumb {
  display: flex;
  align-items: center;
  gap: 8px;
  font-size: 0.82rem;
  color: var(--color-text-light);
  padding: 16px 0;
}

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

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

.breadcrumb span {
  color: var(--color-border);
}

/* ===================================================
   Topic List
   =================================================== */
.topic-list {
  display: flex;
  flex-direction: column;
  gap: 2px;
}

.topic-item {
  display: flex;
  align-items: center;
  gap: 20px;
  padding: 20px 24px;
  background: var(--color-surface);
  border-radius: var(--radius-md);
  border: 1px solid var(--color-border-light);
  transition: all var(--transition);
}

.topic-item:hover {
  border-color: var(--color-accent-light);
  box-shadow: var(--shadow-sm);
  transform: translateX(4px);
}

.topic-num {
  font-size: 1.1rem;
  font-weight: 800;
  color: var(--color-border);
  min-width: 28px;
  text-align: center;
}

.topic-item:nth-child(1) .topic-num { color: #f5a623; }
.topic-item:nth-child(2) .topic-num { color: #9b9b9b; }
.topic-item:nth-child(3) .topic-num { color: #cd7f32; }

.topic-content {
  flex: 1;
}

.topic-title {
  font-size: 0.95rem;
  font-weight: 600;
  color: var(--color-text);
  margin-bottom: 6px;
  transition: color var(--transition);
}

.topic-item:hover .topic-title {
  color: var(--color-accent);
}

.topic-info {
  display: flex;
  gap: 16px;
  font-size: 0.8rem;
  color: var(--color-text-light);
}

.topic-stats {
  display: flex;
  gap: 20px;
  font-size: 0.82rem;
  color: var(--color-text-light);
  flex-shrink: 0;
}

/* ===================================================
   Ranking Table
   =================================================== */
.ranking-list {
  display: flex;
  flex-direction: column;
  gap: 12px;
}

.ranking-item {
  display: flex;
  align-items: center;
  gap: 16px;
  padding: 16px 20px;
  background: var(--color-surface);
  border-radius: var(--radius-md);
  border: 1px solid var(--color-border-light);
  transition: all var(--transition);
}

.ranking-item:hover {
  box-shadow: var(--shadow-sm);
  border-color: var(--color-accent-light);
}

.rank-num {
  font-size: 1.2rem;
  font-weight: 800;
  min-width: 32px;
  text-align: center;
  color: var(--color-border);
}

.ranking-item:nth-child(1) .rank-num { color: #f5a623; }
.ranking-item:nth-child(2) .rank-num { color: #9b9b9b; }
.ranking-item:nth-child(3) .rank-num { color: #cd7f32; }

.rank-avatar {
  width: 44px;
  height: 44px;
  border-radius: 50%;
  background: var(--color-accent-pale);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1rem;
  font-weight: 700;
  color: var(--color-accent);
  flex-shrink: 0;
}

.rank-info {
  flex: 1;
}

.rank-name {
  font-size: 0.95rem;
  font-weight: 600;
  color: var(--color-text);
  margin-bottom: 3px;
}

.rank-desc {
  font-size: 0.8rem;
  color: var(--color-text-light);
}

.rank-stats {
  display: flex;
  gap: 20px;
  font-size: 0.82rem;
  color: var(--color-text-muted);
  flex-shrink: 0;
}

/* ===================================================
   Utility Classes
   =================================================== */
.text-center { text-align: center; }
.text-muted { color: var(--color-text-muted); }
.mt-8 { margin-top: 8px; }
.mt-16 { margin-top: 16px; }
.mt-24 { margin-top: 24px; }
.mt-40 { margin-top: 40px; }
.mb-8 { margin-bottom: 8px; }
.mb-16 { margin-bottom: 16px; }
.mb-24 { margin-bottom: 24px; }
.mb-40 { margin-bottom: 40px; }

.view-all-wrap {
  text-align: center;
  margin-top: 48px;
}

.btn-view-all {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 12px 32px;
  border: 1.5px solid var(--color-border);
  border-radius: var(--radius-md);
  font-size: 0.9rem;
  color: var(--color-text-muted);
  transition: all var(--transition);
}

.btn-view-all:hover {
  border-color: var(--color-accent);
  color: var(--color-accent);
  transform: translateY(-2px);
}

/* ===================================================
   Mobile Responsive
   =================================================== */
@media (max-width: 1024px) {
  .footer-top {
    grid-template-columns: 1fr 1fr;
  }
}

@media (max-width: 768px) {
  .site-nav { display: none; }
  .menu-toggle { display: flex; }

  .site-nav.open {
    display: flex;
    flex-direction: column;
    position: absolute;
    top: 68px;
    left: 0;
    right: 0;
    background: var(--color-surface);
    border-bottom: 1px solid var(--color-border-light);
    padding: 16px 24px;
    gap: 4px;
    box-shadow: var(--shadow-md);
  }

  .hero { min-height: 480px; }
  .hero-stats { gap: 24px; flex-wrap: wrap; }
  .hero-actions { flex-direction: column; align-items: flex-start; }

  .section { padding: 64px 0; }

  .footer-top {
    grid-template-columns: 1fr;
    gap: 32px;
  }

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

  .join-section {
    padding: 48px 28px;
    margin: 0 16px;
  }

  .join-form {
    flex-direction: column;
  }

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

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

  .topic-stats { display: none; }
  .rank-stats { display: none; }

  .search-bar-inner {
    padding: 0 16px;
  }
}

@media (max-width: 480px) {
  .container { padding: 0 16px; }
  .hero-stat-num { font-size: 1.4rem; }
  .testimonials-grid { grid-template-columns: 1fr; }
}

/* ===================================================
   Animations
   =================================================== */
@keyframes fadeInUp {
  from { opacity: 0; transform: translateY(24px); }
  to { opacity: 1; transform: translateY(0); }
}

.animate-in {
  animation: fadeInUp 0.6s cubic-bezier(0.4,0,0.2,1) forwards;
}

.animate-delay-1 { animation-delay: 0.1s; opacity: 0; }
.animate-delay-2 { animation-delay: 0.2s; opacity: 0; }
.animate-delay-3 { animation-delay: 0.3s; opacity: 0; }
.animate-delay-4 { animation-delay: 0.4s; opacity: 0; }

/* ===================================================
   About Page Specific
   =================================================== */
.about-hero-img {
  border-radius: var(--radius-xl);
  overflow: hidden;
  margin-top: 48px;
  max-height: 480px;
  width: 100%;
  object-fit: cover;
}

.about-values {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
  gap: 28px;
  margin-top: 48px;
}

.value-card {
  text-align: center;
  padding: 36px 24px;
  background: var(--color-surface);
  border-radius: var(--radius-lg);
  border: 1px solid var(--color-border-light);
  transition: all var(--transition);
}

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

.value-icon {
  font-size: 2rem;
  margin-bottom: 16px;
}

.value-title {
  font-size: 1rem;
  font-weight: 700;
  margin-bottom: 10px;
  color: var(--color-text);
}

.value-desc {
  font-size: 0.875rem;
  color: var(--color-text-muted);
  line-height: 1.6;
}