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

html,
body {
  font-family: -apple-system, BlinkMacSystemFont, "SF Pro Text", system-ui,
    -system-ui, "PingFang SC", "Microsoft YaHei", sans-serif;
  color: #111827;
  background: #f5f5f7;
  -webkit-font-smoothing: antialiased;
}

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

a {
  color: inherit;
  text-decoration: none;
}

.container {
  width: 100%;
  max-width: 1120px;
  margin: 0 auto;
  padding: 0 16px;
}

.site-header {
  position: sticky;
  top: 0;
  z-index: 20;
  backdrop-filter: blur(20px);
  background: rgba(245, 245, 247, 0.9);
  border-bottom: 1px solid rgba(15, 23, 42, 0.06);
}

.header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 12px 0;
}

.logo {
  font-weight: 700;
  letter-spacing: 0.12em;
  font-size: 14px;
  text-transform: uppercase;
}

.nav {
  display: flex;
  align-items: center;
  gap: 24px;
  font-size: 14px;
}

.nav-link {
  opacity: 0.7;
  transition: opacity 0.2s ease, transform 0.2s ease;
}

.nav-link:hover {
  opacity: 1;
  transform: translateY(-1px);
}

.nav-link.active {
  opacity: 1;
}

.nav-cta {
  padding: 6px 14px;
  border-radius: 999px;
  border: 1px solid rgba(15, 23, 42, 0.12);
  background: #111827;
  color: #f9fafb;
}

.nav-toggle {
  display: none;
  flex-direction: column;
  gap: 3px;
  border: none;
  background: transparent;
  padding: 4px;
}

.nav-toggle span {
  width: 18px;
  height: 1.5px;
  background: #111827;
}

.hero {
  padding: 72px 0 40px;
  background: radial-gradient(circle at top left, #e0f2fe 0, transparent 50%),
    radial-gradient(circle at top right, #fee2e2 0, transparent 50%), #f5f5f7;
}

.hero-inner {
  display: grid;
  grid-template-columns: minmax(0, 3fr) minmax(0, 2.5fr);
  gap: 56px;
  align-items: center;
}

.badge {
  display: inline-flex;
  align-items: center;
  padding: 4px 10px;
  border-radius: 999px;
  background: rgba(15, 23, 42, 0.04);
  font-size: 12px;
  letter-spacing: 0.06em;
  text-transform: uppercase;
  margin-bottom: 16px;
}

.hero h1 {
  font-size: 40px;
  line-height: 1.1;
  letter-spacing: -0.03em;
  margin-bottom: 16px;
}

.hero-subtitle {
  font-size: 15px;
  line-height: 1.7;
  color: #4b5563;
  margin-bottom: 24px;
}

.hero-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-bottom: 12px;
}

.hero-meta {
  font-size: 12px;
  color: #6b7280;
}

.hero-visual {
  display: flex;
  justify-content: flex-end;
}

.gradient-card {
  background: linear-gradient(145deg, #111827, #1f2937);
  border-radius: 28px;
  padding: 24px;
  color: #f9fafb;
  box-shadow: 0 24px 60px rgba(15, 23, 42, 0.38);
  max-width: 360px;
}

.hero-card-label {
  font-size: 12px;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  opacity: 0.7;
  margin-bottom: 8px;
}

.gradient-card h2 {
  font-size: 22px;
  margin-bottom: 12px;
}

.gradient-card ul {
  list-style: none;
  font-size: 14px;
  opacity: 0.9;
  margin-bottom: 16px;
}

.gradient-card li + li {
  margin-top: 4px;
}

.hero-card-footer {
  font-size: 12px;
  opacity: 0.75;
}

.section {
  padding: 56px 0;
}

.section-light {
  background: #ffffff;
}

.section-dark {
  background: #000000;
  color: #f9fafb;
}

.section-inner {
  display: flex;
  flex-direction: column;
  gap: 32px;
}

.section-grid-3 {
  display: grid;
  grid-template-columns: minmax(0, 2.2fr) repeat(2, minmax(0, 1.9fr));
  gap: 24px;
}

.section-grid-2 {
  display: grid;
  grid-template-columns: minmax(0, 2fr) minmax(0, 2fr);
  gap: 32px;
}

.section-title-block h2 {
  font-size: 24px;
  margin-bottom: 12px;
}

.section-title-block p {
  font-size: 14px;
  color: #4b5563;
}

.feature-card {
  background: #f9fafb;
  border-radius: 24px;
  padding: 20px 18px;
  border: 1px solid rgba(15, 23, 42, 0.04);
  box-shadow: 0 14px 35px rgba(15, 23, 42, 0.04);
  font-size: 14px;
}

.feature-card h3 {
  font-size: 16px;
  margin-bottom: 6px;
}

.section-header {
  display: flex;
  align-items: flex-end;
  justify-content: space-between;
  gap: 12px;
}

.section-header h2 {
  font-size: 22px;
}

.link-more {
  font-size: 14px;
  color: #2563eb;
}

.card-row {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 20px;
}

.course-card,
.quote-card {
  background: #ffffff;
  border-radius: 24px;
  padding: 20px 18px;
  border: 1px solid rgba(15, 23, 42, 0.05);
  box-shadow: 0 16px 40px rgba(15, 23, 42, 0.04);
}

.course-card h3 {
  font-size: 16px;
  margin-bottom: 8px;
}

.course-card p {
  font-size: 14px;
  color: #4b5563;
}

.tag-row {
  margin-top: 12px;
  display: flex;
  flex-wrap: wrap;
  gap: 6px;
}

.tag {
  font-size: 11px;
  padding: 3px 8px;
  border-radius: 999px;
  background: #eff6ff;
  color: #1d4ed8;
}

.quote {
  font-size: 14px;
  line-height: 1.7;
  margin-bottom: 10px;
}

.quote-meta {
  font-size: 12px;
  color: #6b7280;
}

.mini-cards-column {
  display: flex;
  flex-direction: column;
  gap: 12px;
}

.mini-card {
  border-radius: 20px;
  padding: 14px 16px;
  background: #050816;
  color: #e5e7eb;
}

.mini-label {
  font-size: 12px;
  opacity: 0.8;
}

.mini-value {
  font-size: 18px;
  margin-top: 4px;
}

.cta-section {
  border-radius: 32px 32px 0 0;
}

.cta-inner {
  align-items: center;
  justify-content: space-between;
}

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 9px 18px;
  border-radius: 999px;
  font-size: 14px;
  border: 1px solid transparent;
  cursor: pointer;
  transition: transform 0.14s ease, box-shadow 0.14s ease,
    background 0.14s ease, color 0.14s ease;
}

.btn-primary {
  background: #111827;
  color: #f9fafb;
  box-shadow: 0 18px 40px rgba(15, 23, 42, 0.35);
}

.btn-primary:hover {
  transform: translateY(-1px);
  box-shadow: 0 20px 50px rgba(15, 23, 42, 0.5);
}

.btn-text {
  background: transparent;
  border-color: rgba(15, 23, 42, 0.1);
}

.btn-text:hover {
  background: rgba(15, 23, 42, 0.03);
}

.btn-large {
  padding: 11px 24px;
}

.site-footer {
  background: #000000;
  color: #9ca3af;
  padding-top: 32px;
}

.footer-inner {
  display: flex;
  justify-content: space-between;
  gap: 32px;
  padding-bottom: 24px;
}

.footer-brand p {
  font-size: 13px;
  margin-top: 8px;
}

.footer-columns {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 24px;
  font-size: 13px;
}

.footer-columns h4 {
  font-size: 13px;
  color: #e5e7eb;
  margin-bottom: 10px;
}

.footer-columns a {
  display: block;
  margin-bottom: 6px;
  opacity: 0.8;
}

.footer-bottom {
  border-top: 1px solid rgba(156, 163, 175, 0.3);
  margin-top: 16px;
}

.footer-bottom-inner {
  padding: 10px 0 18px;
  font-size: 12px;
  color: #6b7280;
}

main,
header,
footer,
section,
article {
  opacity: 0;
  transform: translateY(6px);
  animation: fadeInUp 0.5s ease forwards;
}

header {
  animation-delay: 0s;
}

main {
  animation-delay: 0.05s;
}

section:nth-of-type(1) {
  animation-delay: 0.1s;
}
section:nth-of-type(2) {
  animation-delay: 0.16s;
}
section:nth-of-type(3) {
  animation-delay: 0.22s;
}
section:nth-of-type(4) {
  animation-delay: 0.28s;
}
section:nth-of-type(5) {
  animation-delay: 0.34s;
}

footer {
  animation-delay: 0.38s;
}

@keyframes fadeInUp {
  from {
    opacity: 0;
    transform: translateY(10px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

.page-hero {
  padding: 72px 0 32px;
  background: #f5f5f7;
  border-bottom: 1px solid rgba(15, 23, 42, 0.06);
}

.page-hero h1 {
  font-size: 30px;
  margin-bottom: 8px;
}

.page-hero p {
  font-size: 14px;
  color: #4b5563;
}

.page-main {
  padding: 32px 0 56px;
}

.grid-3 {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 20px;
}

.grid-2 {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 20px;
}

.list-card {
  background: #ffffff;
  border-radius: 20px;
  padding: 18px 16px;
  border: 1px solid rgba(15, 23, 42, 0.05);
  box-shadow: 0 10px 28px rgba(15, 23, 42, 0.03);
}

.list-card h3 {
  font-size: 16px;
  margin-bottom: 6px;
}

.list-card p {
  font-size: 13px;
  color: #4b5563;
}

.teacher-card {
  display: flex;
  gap: 16px;
  align-items: flex-start;
}

.teacher-avatar {
  width: 52px;
  height: 52px;
  border-radius: 50%;
  background: linear-gradient(135deg, #111827, #4f46e5);
}

.teacher-meta {
  flex: 1;
}

.teacher-meta h3 {
  font-size: 15px;
  margin-bottom: 2px;
}

.teacher-meta .role {
  font-size: 12px;
  color: #6b7280;
  margin-bottom: 6px;
}

.teacher-meta p {
  font-size: 13px;
  color: #4b5563;
}

.testimonial-card {
  background: #ffffff;
  border-radius: 20px;
  padding: 18px 16px;
  border: 1px solid rgba(15, 23, 42, 0.05);
  font-size: 13px;
}

.testimonial-card .name {
  margin-top: 10px;
  font-size: 12px;
  color: #6b7280;
}

.form-card {
  max-width: 520px;
  background: #ffffff;
  border-radius: 24px;
  padding: 22px 20px;
  border: 1px solid rgba(15, 23, 42, 0.06);
  box-shadow: 0 18px 46px rgba(15, 23, 42, 0.06);
}

.form-row {
  display: flex;
  gap: 12px;
}

.form-field {
  flex: 1;
  display: flex;
  flex-direction: column;
  gap: 4px;
  margin-bottom: 12px;
}

label {
  font-size: 12px;
  color: #4b5563;
}

input,
select,
textarea {
  border-radius: 999px;
  border: 1px solid rgba(15, 23, 42, 0.12);
  padding: 8px 12px;
  font-size: 13px;
  outline: none;
  background: #f9fafb;
}

textarea {
  border-radius: 16px;
  min-height: 96px;
  resize: vertical;
}

input:focus,
select:focus,
textarea:focus {
  border-color: #111827;
  background: #ffffff;
}

.form-footer {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-top: 12px;
  font-size: 12px;
  color: #6b7280;
}

@media (max-width: 900px) {
  .hero-inner {
    grid-template-columns: minmax(0, 1fr);
    gap: 32px;
  }

  .hero-visual {
    justify-content: flex-start;
  }

  .section-grid-3 {
    grid-template-columns: minmax(0, 1.1fr);
  }

  .section-grid-2 {
    grid-template-columns: minmax(0, 1fr);
  }

  .card-row,
  .grid-3,
  .grid-2 {
    grid-template-columns: minmax(0, 1fr);
  }

  .footer-inner {
    flex-direction: column;
  }

  .footer-columns {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }
}

@media (max-width: 720px) {
  .nav {
    position: fixed;
    inset: 56px 16px auto;
    padding: 12px 14px;
    border-radius: 16px;
    background: rgba(245, 245, 247, 0.98);
    border: 1px solid rgba(15, 23, 42, 0.08);
    flex-direction: column;
    align-items: flex-start;
    gap: 10px;
    transform: scale(0.96);
    opacity: 0;
    pointer-events: none;
    transform-origin: top right;
    transition: opacity 0.18s ease, transform 0.18s ease;
  }

  .nav.open {
    opacity: 1;
    pointer-events: auto;
    transform: scale(1);
  }

  .nav-toggle {
    display: flex;
  }

  .hero {
    padding-top: 56px;
  }

  .site-header {
    position: sticky;
  }

  .footer-columns {
    grid-template-columns: minmax(0, 1fr);
  }
}