/* ============================================================
   MindSpore — Official Site Styles
   Layout & design inspired by mindspore.cn/en
   ============================================================ */

:root {
  --color-primary: #5F81FF;
  --color-primary-light: #73B3FF;
  --color-primary-gradient: linear-gradient(135deg, #8FF4FF 0%, #73B3FF 51.76%, #5F81FF 100%);
  --color-bg: #0A0E27;
  --color-bg-secondary: #0D1136;
  --color-bg-card: #121842;
  --color-text: #E8EAF0;
  --color-text-secondary: #9498B0;
  --color-text-muted: #6B6F8A;
  --color-border: #1E2350;
  --color-link: #73B3FF;
  --color-link-hover: #8FF4FF;
  --color-success: #52C41A;
  --color-warning: #FAAD14;
  --color-hot-tag: #FF4D4F;
  --color-hot-bg: rgba(255,77,79,0.15);
  --font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Helvetica, Arial, sans-serif;
  --max-width: 1200px;
  --header-height: 64px;
}

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

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

body {
  font-family: var(--font-family);
  background-color: var(--color-bg);
  color: var(--color-text);
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

a {
  color: var(--color-link);
  text-decoration: none;
  transition: color 0.2s;
}
a:hover {
  color: var(--color-link-hover);
}

img {
  max-width: 100%;
  vertical-align: middle;
}

ul, ol {
  list-style: none;
}

.container {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0 24px;
}

/* Section styling */
.section {
  padding: 80px 0;
}
.section-title {
  font-size: 2rem;
  font-weight: 700;
  text-align: center;
  margin-bottom: 12px;
  background: var(--color-primary-gradient);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}
.section-subtitle {
  text-align: center;
  color: var(--color-text-secondary);
  font-size: 1.05rem;
  max-width: 600px;
  margin: 0 auto 48px;
}
.section-divider {
  width: 60px;
  height: 3px;
  background: var(--color-primary-gradient);
  margin: 0 auto 48px;
  border-radius: 2px;
}

/* ===== HEADER ===== */
.app-header {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 1000;
  height: var(--header-height);
  background: rgba(10, 14, 39, 0.92);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--color-border);
}

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

.header-logo {
  display: flex;
  align-items: center;
  gap: 8px;
}
.header-logo .logo {
  height: 28px;
  width: auto;
}

/* Navigation */
.header-nav {
  display: flex;
  align-items: center;
}

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

.nav-item {
  position: relative;
}

.nav-label {
  display: block;
  padding: 8px 14px;
  font-size: 0.85rem;
  font-weight: 500;
  color: var(--color-text);
  border-radius: 8px;
  cursor: pointer;
  transition: background 0.2s, color 0.2s;
}
.nav-label:hover {
  background: rgba(115, 179, 255, 0.1);
  color: var(--color-link);
}

/* Dropdown */
.sub-nav {
  position: absolute;
  top: 100%;
  left: 50%;
  transform: translateX(-50%);
  padding-top: 12px;
  opacity: 0;
  visibility: hidden;
  transition: opacity 0.2s, visibility 0.2s;
  min-width: 200px;
}
.nav-item:hover .sub-nav {
  opacity: 1;
  visibility: visible;
}

.sub-nav-content {
  background: var(--color-bg-card);
  border: 1px solid var(--color-border);
  border-radius: 12px;
  padding: 16px;
  box-shadow: 0 8px 32px rgba(0,0,0,0.4);
  display: flex;
  gap: 24px;
}

.sub-nav-panel h3 {
  font-size: 0.8rem;
  font-weight: 600;
  color: var(--color-text-muted);
  text-transform: uppercase;
  letter-spacing: 0.05em;
  margin-bottom: 8px;
}
.sub-nav-panel ul {
  display: flex;
  flex-direction: column;
  gap: 4px;
}
.sub-nav-item a {
  display: block;
  padding: 6px 8px;
  font-size: 0.88rem;
  color: var(--color-text-secondary);
  border-radius: 6px;
  transition: background 0.2s, color 0.2s;
}
.sub-nav-item a:hover {
  background: rgba(115, 179, 255, 0.08);
  color: var(--color-text);
}

.shortcut-panel {
  border-left: 1px solid var(--color-border);
  padding-left: 20px;
  min-width: 200px;
}
.shortcut-link {
  font-size: 0.8rem;
  font-weight: 600;
  color: var(--color-text-muted);
  text-transform: uppercase;
  letter-spacing: 0.05em;
  margin-bottom: 8px;
}
.shortcut-item {
  display: flex;
  align-items: center;
  gap: 10px;
  padding: 8px;
  border-radius: 8px;
  transition: background 0.2s;
}
.shortcut-item:hover {
  background: rgba(115, 179, 255, 0.08);
}
.shortcut-item .title {
  font-size: 0.88rem;
  color: var(--color-text-secondary);
}

/* Tag */
.o-tag {
  display: inline-flex;
  align-items: center;
  padding: 1px 6px;
  font-size: 0.7rem;
  font-weight: 600;
  border-radius: 100px;
  margin-left: 4px;
}
.o-tag-hot {
  background: var(--color-hot-bg);
  color: var(--color-hot-tag);
}

/* Mobile menu toggle */
.mobile-menu-toggle {
  display: none;
  background: none;
  border: none;
  color: var(--color-text);
  font-size: 1.5rem;
  cursor: pointer;
  padding: 8px;
}

/* ===== HERO ===== */
.hero {
  min-height: 100vh;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  text-align: center;
  padding: 120px 24px 80px;
  background: radial-gradient(ellipse at 50% 0%, rgba(95, 129, 255, 0.12) 0%, transparent 60%),
              radial-gradient(ellipse at 80% 100%, rgba(143, 244, 255, 0.06) 0%, transparent 50%);
  position: relative;
  overflow: hidden;
}

.hero ::selection {
  background: var(--color-primary);
  color: white;
}

.hero-badge {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 6px 16px;
  background: rgba(115, 179, 255, 0.1);
  border: 1px solid rgba(115, 179, 255, 0.2);
  border-radius: 100px;
  font-size: 0.85rem;
  color: var(--color-link);
  margin-bottom: 24px;
}
.hero-badge span {
  font-weight: 600;
}

.hero h1 {
  font-size: 3.5rem;
  font-weight: 800;
  line-height: 1.15;
  margin-bottom: 16px;
  letter-spacing: -0.02em;
}
.hero h1 .gradient-text {
  background: var(--color-primary-gradient);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.hero p {
  font-size: 1.2rem;
  color: var(--color-text-secondary);
  max-width: 640px;
  margin: 0 auto 32px;
  line-height: 1.7;
}

.hero-actions {
  display: flex;
  gap: 16px;
  justify-content: center;
  flex-wrap: wrap;
}

.btn {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 14px 32px;
  font-size: 1rem;
  font-weight: 600;
  border-radius: 12px;
  border: none;
  cursor: pointer;
  transition: all 0.25s;
}
.btn-primary {
  background: var(--color-primary-gradient);
  color: white;
}
.btn-primary:hover {
  transform: translateY(-2px);
  box-shadow: 0 8px 24px rgba(95, 129, 255, 0.35);
  color: white;
}
.btn-outline {
  background: transparent;
  color: var(--color-text);
  border: 1px solid var(--color-border);
}
.btn-outline:hover {
  border-color: var(--color-link);
  color: var(--color-link);
  transform: translateY(-2px);
}

.hero-features {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 24px;
  margin-top: 64px;
  max-width: 900px;
  width: 100%;
}

.hero-feature {
  padding: 24px;
  background: rgba(18, 24, 66, 0.6);
  border: 1px solid var(--color-border);
  border-radius: 16px;
  text-align: left;
  transition: border-color 0.2s, transform 0.2s;
}
.hero-feature:hover {
  border-color: rgba(115, 179, 255, 0.3);
  transform: translateY(-4px);
}

.hero-feature h3 {
  font-size: 1rem;
  font-weight: 600;
  margin-bottom: 8px;
  color: var(--color-text);
}

.hero-feature p {
  font-size: 0.88rem;
  color: var(--color-text-muted);
  margin: 0;
  line-height: 1.6;
}

/* ===== QUICK CARDS (Knowledge Map, Tutorials, etc.) ===== */
.quick-cards {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 20px;
}

.quick-card {
  background: var(--color-bg-card);
  border: 1px solid var(--color-border);
  border-radius: 16px;
  padding: 32px 24px;
  text-align: center;
  transition: border-color 0.2s, transform 0.2s;
}
.quick-card:hover {
  border-color: rgba(115, 179, 255, 0.3);
  transform: translateY(-4px);
}

.quick-card .icon {
  width: 48px;
  height: 48px;
  margin: 0 auto 16px;
  background: var(--color-primary-gradient);
  border-radius: 14px;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.3rem;
  color: white;
}

.quick-card h3 {
  font-size: 1.05rem;
  font-weight: 600;
  margin-bottom: 8px;
}

.quick-card p {
  font-size: 0.88rem;
  color: var(--color-text-muted);
  line-height: 1.6;
}

/* ===== FEATURES GRID (AI4S, etc.) ===== */
.features-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 20px;
}

.feature-card {
  background: var(--color-bg-card);
  border: 1px solid var(--color-border);
  border-radius: 16px;
  padding: 32px 24px;
  transition: border-color 0.2s, transform 0.2s;
}
.feature-card:hover {
  border-color: rgba(115, 179, 255, 0.3);
  transform: translateY(-4px);
}

.feature-card .icon {
  width: 40px;
  height: 40px;
  margin-bottom: 14px;
  background: var(--color-primary-gradient);
  border-radius: 12px;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.1rem;
  color: white;
}

.feature-card h3 {
  font-size: 1.05rem;
  font-weight: 600;
  margin-bottom: 8px;
}

.feature-card p {
  font-size: 0.88rem;
  color: var(--color-text-muted);
  line-height: 1.6;
}

/* ===== INSTALL SECTION ===== */
.install-section {
  background: var(--color-bg-secondary);
}

.install-commands {
  background: var(--color-bg-card);
  border: 1px solid var(--color-border);
  border-radius: 16px;
  padding: 32px;
  margin-bottom: 32px;
}

.install-commands .command-label {
  font-size: 0.85rem;
  color: var(--color-text-muted);
  margin-bottom: 8px;
}

.install-commands .command-block {
  background: rgba(0,0,0,0.3);
  border: 1px solid var(--color-border);
  border-radius: 10px;
  padding: 14px 18px;
  font-family: 'SF Mono', 'Fira Code', monospace;
  font-size: 0.93rem;
  color: var(--color-text);
  margin-bottom: 16px;
  overflow-x: auto;
  display: flex;
  align-items: center;
  justify-content: space-between;
}
.install-commands .command-block code {
  white-space: nowrap;
}
.install-commands .command-block .copy-btn {
  background: none;
  border: none;
  color: var(--color-text-muted);
  cursor: pointer;
  padding: 4px 8px;
  border-radius: 6px;
  transition: background 0.2s;
}
.install-commands .command-block .copy-btn:hover {
  background: rgba(255,255,255,0.05);
  color: var(--color-text);
}

.install-note {
  font-size: 0.88rem;
  color: var(--color-text-muted);
  margin-bottom: 24px;
}
.install-note a {
  color: var(--color-link);
}

.cloud-platforms {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 20px;
}

.cloud-card {
  background: var(--color-bg-card);
  border: 1px solid var(--color-border);
  border-radius: 16px;
  padding: 24px;
  transition: border-color 0.2s;
}
.cloud-card:hover {
  border-color: rgba(115, 179, 255, 0.3);
}
.cloud-card h4 {
  font-size: 1rem;
  font-weight: 600;
  margin-bottom: 6px;
}
.cloud-card p {
  font-size: 0.88rem;
  color: var(--color-text-muted);
  line-height: 1.6;
}

/* ===== LEARNING SECTION ===== */
.learning-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 20px;
}

.learning-card {
  background: var(--color-bg-card);
  border: 1px solid var(--color-border);
  border-radius: 16px;
  padding: 24px;
  text-align: center;
  transition: border-color 0.2s, transform 0.2s;
}
.learning-card:hover {
  border-color: rgba(115, 179, 255, 0.3);
  transform: translateY(-4px);
}

.learning-card .icon-circle {
  width: 56px;
  height: 56px;
  margin: 0 auto 16px;
  background: var(--color-primary-gradient);
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.2rem;
  color: white;
}

.learning-card h4 {
  font-size: 1rem;
  font-weight: 600;
  margin-bottom: 6px;
}

.learning-card p {
  font-size: 0.85rem;
  color: var(--color-text-muted);
  line-height: 1.5;
}

/* ===== REPOSITORIES ===== */
.repos-section {
  background: var(--color-bg-secondary);
}

.repo-cards {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 20px;
}

.repo-card {
  background: var(--color-bg-card);
  border: 1px solid var(--color-border);
  border-radius: 16px;
  padding: 28px 24px;
  transition: border-color 0.2s, transform 0.2s;
}
.repo-card:hover {
  border-color: rgba(115, 179, 255, 0.3);
  transform: translateY(-4px);
}

.repo-card .repo-icon {
  width: 44px;
  height: 44px;
  margin-bottom: 16px;
  background: var(--color-primary-gradient);
  border-radius: 12px;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1rem;
  color: white;
}

.repo-card h4 {
  font-size: 1.05rem;
  font-weight: 600;
  margin-bottom: 8px;
}

.repo-card p {
  font-size: 0.88rem;
  color: var(--color-text-muted);
  line-height: 1.6;
  margin-bottom: 16px;
}

.repo-card .repo-link {
  font-size: 0.88rem;
  font-weight: 500;
  color: var(--color-link);
  display: inline-flex;
  align-items: center;
  gap: 6px;
}

/* ===== CONTACT & HELP ===== */
.contact-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 20px;
}

.contact-card {
  background: var(--color-bg-card);
  border: 1px solid var(--color-border);
  border-radius: 16px;
  padding: 28px 24px;
  text-align: center;
  transition: border-color 0.2s;
}
.contact-card:hover {
  border-color: rgba(115, 179, 255, 0.3);
}

.contact-card .contact-icon {
  width: 48px;
  height: 48px;
  margin: 0 auto 16px;
  background: var(--color-primary-gradient);
  border-radius: 14px;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.2rem;
  color: white;
}

.contact-card h4 {
  font-size: 1rem;
  font-weight: 600;
  margin-bottom: 6px;
}

.contact-card p {
  font-size: 0.88rem;
  color: var(--color-text-muted);
  line-height: 1.6;
}

.contact-card .contact-email {
  font-size: 0.88rem;
  color: var(--color-link);
  word-break: break-all;
}

/* ===== PARTNERS ===== */
.partners-section {
  background: var(--color-bg-secondary);
  text-align: center;
}

.partners-section p {
  color: var(--color-text-muted);
  font-size: 1rem;
}

/* ===== FOOTER ===== */
.footer {
  padding: 32px 0;
  border-top: 1px solid var(--color-border);
}

.footer-content {
  display: flex;
  justify-content: space-between;
  align-items: center;
  flex-wrap: wrap;
  gap: 16px;
}

.footer-links {
  display: flex;
  gap: 20px;
  flex-wrap: wrap;
}

.footer-links a {
  font-size: 0.85rem;
  color: var(--color-text-muted);
  transition: color 0.2s;
}
.footer-links a:hover {
  color: var(--color-text);
}

.footer-copyright {
  font-size: 0.85rem;
  color: var(--color-text-muted);
}

/* ===== RESPONSIVE ===== */
@media (max-width: 1024px) {
  .hero h1 { font-size: 2.8rem; }
  .quick-cards,
  .learning-grid { grid-template-columns: repeat(2, 1fr); }
  .features-grid,
  .repo-cards,
  .contact-grid { grid-template-columns: repeat(2, 1fr); }
}

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

  .header-nav {
    position: fixed;
    top: var(--header-height);
    left: 0;
    right: 0;
    background: var(--color-bg);
    border-bottom: 1px solid var(--color-border);
    padding: 16px 24px;
    flex-direction: column;
    align-items: stretch;
    transform: translateY(-100%);
    opacity: 0;
    transition: transform 0.3s, opacity 0.3s;
    pointer-events: none;
  }
  .header-nav.open {
    transform: translateY(0);
    opacity: 1;
    pointer-events: all;
  }
  .nav-list { flex-direction: column; }
  .nav-item .sub-nav { display: none; }

  .hero { padding: 100px 20px 60px; }
  .hero h1 { font-size: 2.2rem; }
  .hero p { font-size: 1rem; }
  .hero-features { grid-template-columns: 1fr; }
  .hero-actions { flex-direction: column; align-items: center; }
  .btn { width: 100%; max-width: 320px; justify-content: center; }

  .quick-cards,
  .learning-grid,
  .features-grid,
  .repo-cards,
  .contact-grid { grid-template-columns: 1fr; }
  .cloud-platforms { grid-template-columns: 1fr; }

  .section { padding: 48px 0; }
  .section-title { font-size: 1.6rem; }

  .footer-content { flex-direction: column; text-align: center; }
  .footer-links { justify-content: center; }
}

@media (max-width: 480px) {
  .hero h1 { font-size: 1.8rem; }
}