:root {
  --primary: #5fbf5a;
  --primary-dark: #20863a;
  --accent: #8fd26f;
  --sun: #f6c447;
  --sky: #dceefa;
  --bg: #f7f8f5;
  --paper: #ffffff;
  --text: #222222;
  --muted: #60716a;
  --line: #f0f2ee;
  --shadow: 0 18px 42px rgba(30, 80, 48, 0.12);
  --shadow-hover: 0 14px 34px rgba(30, 80, 48, 0.16);
  --shadow-hover-strong: 0 18px 44px rgba(30, 80, 48, 0.18);
  --max: 1180px;
  --page-gutter: 7vw;
  --brand-width: 96px;
  --header-gap: 34px;
  --hero-copy-offset: calc(var(--page-gutter) + var(--brand-width) + var(--header-gap) - ((100vw - var(--max)) / 2) - 24px);
  --hero-nav-gap: 10svh;
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
  text-size-adjust: 100%;
}

body {
  margin: 0;
  color: var(--text);
  background: var(--bg);
  font-family: "PingFang SC", "Microsoft YaHei", "Noto Sans CJK SC", Arial, sans-serif;
  line-height: 1.6;
  overflow-x: hidden;
}

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

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

button {
  font: inherit;
}

.site-header {
  position: fixed;
  inset: 0 0 auto;
  z-index: 20;
  display: grid;
  grid-template-columns: auto 1fr auto;
  align-items: center;
  gap: var(--header-gap);
  width: 100%;
  padding: 22px var(--page-gutter);
  transition: background-color 180ms ease, box-shadow 180ms ease, padding 180ms ease;
}

.site-header.is-scrolled {
  padding-block: 13px;
  background: rgba(255, 255, 255, 0.9);
  box-shadow: 0 10px 30px rgba(26, 67, 43, 0.08);
  backdrop-filter: blur(14px);
}

.brand {
  width: var(--brand-width);
}

.nav {
  display: flex;
  gap: clamp(18px, 2.4vw, 34px);
  align-items: center;
  font-size: 16px;
  font-weight: 700;
  white-space: nowrap;
}

.nav a {
  position: relative;
  padding: 8px 0;
}

.nav a::after {
  position: absolute;
  left: 0;
  right: 0;
  bottom: 0;
  height: 2px;
  content: "";
  background: var(--primary-dark);
  transform: scaleX(0);
  transform-origin: left;
  transition: transform 180ms ease;
}

.nav a:hover::after,
.nav a:focus-visible::after {
  transform: scaleX(1);
}

.platform-shortcuts-wrap {
  padding: 4px;
  /*border: 1px solid rgba(34, 134, 58, 0.16);*/
  border-radius: 14px;
  background: rgba(255, 255, 255, 0.92);
  /*box-shadow: 0 8px 20px rgba(26, 67, 43, 0.1);*/
}

.platform-shortcuts {
  display: flex;
  gap: 8px;
}

.menu-toggle,
.feedback-arrow {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  border: 1px solid rgba(34, 134, 58, 0.24);
  background: rgba(255, 255, 255, 0.86);
  box-shadow: 0 8px 20px rgba(26, 67, 43, 0.1);
  transition: transform 180ms ease, box-shadow 180ms ease, border-color 180ms ease, background-color 180ms ease;
}

.platform-shortcuts a {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 44px;
  height: 44px;
  border-radius: 10px;
  overflow: hidden;
}

.platform-shortcuts a img {
  width: 34px;
  height: 34px;
  object-fit: cover;
  display: block;
  border-radius: 8px;
}

.store-icon-img {
  width: 44px;
  height: 44px;
  object-fit: contain;
  flex: 0 0 auto;
}

.menu-toggle {
  display: none;
  width: 44px;
  height: 44px;
  border-radius: 8px;
  cursor: pointer;
}

.menu-toggle span {
  position: absolute;
  width: 20px;
  height: 2px;
  background: var(--primary-dark);
  transition: transform 180ms ease;
}

.menu-toggle span:first-child {
  transform: translateY(-5px);
}

.menu-toggle span:last-child {
  transform: translateY(5px);
}

.menu-toggle.is-open span:first-child {
  transform: rotate(45deg);
}

.menu-toggle.is-open span:last-child {
  transform: rotate(-45deg);
}

.menu-toggle:hover,
.menu-toggle:focus-visible {
  transform: translateY(-2px);
  border-color: rgba(32, 134, 58, 0.44);
  box-shadow: 0 12px 26px rgba(26, 67, 43, 0.14);
}

.hero {
  position: relative;
  min-height: 82svh;
  overflow: hidden;
  background: var(--sky);
}

.hero-bg {
  position: absolute;
  inset: 0;
  background:
    linear-gradient(90deg, rgba(255, 255, 255, 0.38) 0%, rgba(255, 255, 255, 0.24) 18%, rgba(255, 255, 255, 0) 50%),
    linear-gradient(180deg, rgba(255, 255, 255, 0) 0%, rgba(247, 248, 245, 0.02) 70%, rgba(247, 248, 245, 0.82) 100%),
    url("./assets/course-bg.png") center / cover no-repeat;
  transform: translate3d(0, var(--parallax, 0px), 0) scale(1.05);
  transform-origin: center top;
}

.hero-content {
  position: relative;
  display: grid;
  grid-template-columns: minmax(320px, 560px) minmax(280px, 1fr);
  grid-template-rows: 1fr auto;
  gap: 22px clamp(28px, 4vw, 56px);
  align-items: center;
  max-width: var(--max);
  min-height: 82svh;
  margin: 0 auto;
  padding: calc(64px + var(--hero-nav-gap)) 24px 38px;
}

.hero-copy {
  align-self: start;
  padding-top: 0;
}

.hero h1 {
  margin: 0;
  color: #183c25;
  font-size: clamp(36px, 4vw, 46px);
  line-height: 1.18;
}

.hero-subtitle {
  margin: 8px 0 26px;
  color: #173421;
  font-size: clamp(24px, 2.7vw, 30px);
  font-weight: 800;
  line-height: 1.35;
}

.hero-text {
  max-width: 480px;
  margin: 0 0 30px;
  color: #263c31;
  font-size: clamp(17px, 1.8vw, 20px);
  font-weight: 700;
}

.primary-cta {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-width: 150px;
  min-height: 54px;
  padding: 0 28px;
  color: #ffffff;
  background: linear-gradient(135deg, var(--primary) 0%, var(--primary-dark) 100%);
  border-radius: 999px;
  box-shadow: 0 14px 28px rgba(32, 134, 58, 0.24);
  font-size: 18px;
  font-weight: 800;
  transition: transform 180ms ease, box-shadow 180ms ease, filter 180ms ease;
}

.primary-cta:hover {
  transform: translateY(-2px);
  box-shadow: 0 18px 34px rgba(32, 134, 58, 0.3);
  filter: saturate(1.02);
}

.primary-cta:focus-visible {
  transform: translateY(-2px);
  box-shadow: 0 18px 34px rgba(32, 134, 58, 0.3);
}

.phone-stage {
  justify-self: center;
  align-self: end;
  margin-bottom: -82px;
  margin-right: clamp(36px, 8vw, 148px);
}

.phone-stage > img {
  display: block;
  width: min(860px, 56vw);
  max-height: none;
  object-fit: contain;
  object-position: center bottom;
  transform: scale(1.42);
  transform-origin: center bottom;
}



.section,
.feedback-band,
.download-section {
  padding: 66px 24px;
  background: #ffffff;
}

.feedback-band {
  background: #f9fbfa;
  border-top: 1px solid #f0f2ee;
}

.download-section {
  padding-top: 66px;
  border-top: 1px solid rgba(95, 191, 90, 0.12);
}

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

.section-heading h2 {
  position: relative;
  display: inline-block;
  margin: 0 0 42px;
  font-size: 28px;
  line-height: 1.2;
}

.section-heading h2::after {
  position: absolute;
  left: 50%;
  bottom: -16px;
  width: 72px;
  height: 3px;
  content: "";
  background: linear-gradient(90deg, rgba(95, 191, 90, 0), var(--primary), rgba(95, 191, 90, 0));
  transform: translateX(-50%);
}

.feature-grid {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: 26px;
  max-width: 1040px;
  margin: 0 auto;
}

.feature-card,
.feedback-card,
.download-card {
  border: 1px solid var(--line);
  border-radius: 8px;
  background: rgba(255, 255, 255, 0.92);
  box-shadow: 0 8px 22px rgba(35, 91, 51, 0.06);
  transition: transform 220ms ease, box-shadow 220ms ease, border-color 220ms ease, background-color 220ms ease;
}

.feature-card:hover,
.feature-card:focus-within {
  border-color: rgba(32, 134, 58, 0.48);
  box-shadow: var(--shadow-hover);
  transform: none;
}

.feedback-card:hover,
.feedback-card:focus-within {
  position: relative;
  z-index: 2;
  border-color: rgba(32, 134, 58, 0.44);
  box-shadow: none;
  transform: none;
}

.feature-card {
  display: flex;
  flex-direction: column;
  min-height: 330px;
  padding: 22px 22px 16px;
}

.feature-card img {
  width: 100%;
  height: 136px;
  object-fit: contain;
  object-position: center;
  margin-top: auto;
}

.feature-card h3 {
  margin: 12px 0 8px;
  font-size: 20px;
  line-height: 1.25;
}

.feature-card p {
  margin: 0;
  color: #34443b;
  font-size: 14px;
  font-weight: 700;
  line-height: 1.55;
}

.feature-card .feature-mark-img {
  align-self: flex-start;
  width: 35px;
  height: 35px;
  object-fit: contain;
  margin-top: 0;
}

.feedback-wrap {
  display: grid;
  grid-template-columns: 52px minmax(0, 1fr) 52px;
  gap: 28px;
  align-items: center;
  max-width: 1180px;
  margin: 0 auto;
}

.feedback-grid {
  display: flex;
  gap: 30px;
  overflow-x: auto;
  padding: 18px 0 22px;
  margin: -18px 0 -22px;
  scroll-behavior: auto;
  scroll-snap-type: none;
  scrollbar-width: none;
}

.feedback-grid::-webkit-scrollbar {
  display: none;
}

.feedback-grid .feedback-card {
  flex: 0 0 calc((100% - 30px) / 2);
}

.feedback-grid .feedback-card:last-child {
  margin-right: 0;
}

.feature-grid {
  gap: 30px;
}

.feedback-card {
  min-height: 230px;
  padding: 26px 26px;
  box-shadow: none;
}

.person {
  display: flex;
  gap: 12px;
  align-items: center;
  margin-bottom: 12px;
}

.portrait {
  width: 46px;
  height: 46px;
  flex: 0 0 46px;
  object-fit: cover;
  object-position: center;
  border-radius: 50%;
  border: 3px solid #ffffff;
  box-shadow: 0 8px 20px rgba(35, 91, 51, 0.14);
}

.person h3 {
  margin: 0;
  font-size: 16px;
}

.person p {
  margin: 1px 0 0;
  color: var(--primary);
  font-size: 13px;
  line-height: 1;
}

blockquote {
  position: relative;
  display: -webkit-box;
  overflow: hidden;
  margin: 0;
  color: #293830;
  font-size: 14px;
  font-weight: 600;
  line-height: 1.58;
  -webkit-box-orient: vertical;
  -webkit-line-clamp: 6;
}

blockquote::after {
  position: absolute;
  right: 0;
  bottom: -18px;
  content: "”";
  color: var(--primary);
  font-size: 42px;
  font-weight: 900;
  line-height: 1;
}

.feedback-arrow {
  width: 52px;
  height: 52px;
  padding: 0;
  border: 0;
  background: transparent;
  box-shadow: none;
  border-radius: 50%;
  cursor: pointer;
}

.feedback-arrow span {
  width: 18px;
  height: 18px;
  border-left: 4px solid var(--primary-dark);
  border-bottom: 4px solid var(--primary-dark);
  transform: rotate(45deg);
}

.feedback-arrow-next span {
  transform: rotate(225deg);
}

.feedback-arrow:hover {
  background: transparent;
  box-shadow: none;
  transform: translateY(-2px);
}

.feedback-arrow:focus-visible {
  background: transparent;
  box-shadow: none;
  transform: translateY(-2px);
}

.download-grid {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 22px;
  max-width: 870px;
  margin: 0 auto;
}

.download-card {
  display: grid;
  grid-template-columns: 46px 1fr 56px;
  gap: 14px;
  align-items: center;
  min-height: 86px;
  padding: 12px 16px;
}

.download-card:hover,
.download-card:focus-visible,
.download-card.reveal.is-visible:hover,
.download-card.reveal.is-visible:focus-visible {
  border-color: var(--line);
  box-shadow: 0 14px 34px rgba(35, 91, 51, 0.14);
  transform: translateY(0);
}

.download-card strong,
.download-card small {
  display: block;
}

.download-card strong {
  font-size: 16px;
}

.download-card small {
  color: var(--muted);
  font-size: 12px;
  font-weight: 700;
}

.download-qr-img {
  width: 52px;
  height: 52px;
  object-fit: contain;
  justify-self: end;
  border-radius: 6px;
  transition: transform 180ms ease, box-shadow 180ms ease;
  transform-origin: center right;
}

.download-card:hover .download-qr-img,
.download-card:focus-visible .download-qr-img {
  position: relative;
  z-index: 4;
  transform: scale(3.1);
  box-shadow: 0 10px 22px rgba(22, 54, 35, 0.14);
}

.site-footer {
  display: grid;
  grid-template-columns: 1.1fr 1.2fr auto;
  gap: 52px;
  padding: 48px 7vw 36px;
  background: #ffffff;
  border-top: 1px solid rgba(34, 34, 34, 0.06);
}

.footer-brand {
  display: flex;
  align-items: center;
  gap: 16px;
}

.footer-brand img {
  width: 96px;
  flex: 0 0 auto;
}

.footer-brand p,
.footer-contact p,
.copyright {
  margin: 0;
  color: #38473f;
  font-size: 14px;
  font-weight: 600;
}

.footer-contact h2,
.footer-social h2 {
  margin: 0 0 16px;
  font-size: 18px;
}

.footer-contact p + p {
  margin-top: 6px;
}

.footer-contact a {
  color: #1f7d3a;
  font-weight: 800;
}

.footer-social > div {
  display: flex;
  gap: 18px;
}

.social {
  position: relative;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 48px;
  height: 48px;
  padding: 0;
  color: #ffffff;
  background: transparent;
  border: 0;
  appearance: none;
  border-radius: 8px;
  font-size: 14px;
  font-weight: 900;
  text-decoration: none;
  cursor: pointer;
  transition: transform 180ms ease, box-shadow 180ms ease;
}

.social:hover,
.social:focus-visible {
  transform: translateY(-2px);
  box-shadow: 0 12px 28px rgba(21, 61, 35, 0.18);
}

.social-qr {
  position: absolute;
  left: 50%;
  bottom: calc(100% + 14px);
  z-index: 5;
  width: 150px;
  height: 154px;
  padding: 8px;
  pointer-events: none;
  background: #ffffff;
  border: 1px solid rgba(34, 134, 58, 0.16);
  border-radius: 12px;
  box-shadow: 0 18px 44px rgba(22, 54, 35, 0.18);
  opacity: 0;
  transform: translateX(-50%) translateY(8px) scale(0.86);
  transform-origin: center bottom;
  transition: opacity 180ms ease, transform 180ms ease;
}

.social-qr::after {
  position: absolute;
  left: 50%;
  bottom: -7px;
  width: 14px;
  height: 14px;
  content: "";
  background: #ffffff;
  border-right: 1px solid rgba(34, 134, 58, 0.16);
  border-bottom: 1px solid rgba(34, 134, 58, 0.16);
  transform: translateX(-50%) rotate(45deg);
}

.social-qr img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  border-radius: 8px;
}

.social:hover .social-qr,
.social:focus-visible .social-qr {
  opacity: 1;
  transform: translateX(-50%) translateY(0) scale(1);
}

.copyright {
  grid-column: 1 / -1;
  padding-top: 14px;
}

.reveal {
  opacity: 0;
  transform: translateY(24px);
  transition: opacity 520ms ease, transform 520ms ease;
}

.reveal.is-visible {
  opacity: 1;
  transform: translateY(0);
}

.hero-copy.reveal {
  transform: translate(var(--hero-copy-offset), 24px);
}

.hero-copy.reveal.is-visible {
  transform: translate(var(--hero-copy-offset), 0);
}

.feature-card.reveal,
.feedback-card.reveal,
.download-card.reveal {
  transition: opacity 520ms ease, transform 220ms ease, box-shadow 220ms ease, border-color 220ms ease, background-color 220ms ease;
}

.feature-card.reveal.is-visible:hover,
.feature-card.reveal.is-visible:focus-within {
  border-color: rgba(32, 134, 58, 0.48);
  box-shadow: var(--shadow-hover);
  transform: translateY(0);
}

.feedback-card.reveal.is-visible:hover,
.feedback-card.reveal.is-visible:focus-within {
  position: relative;
  z-index: 2;
  border-color: rgba(32, 134, 58, 0.44);
  box-shadow: none;
  transform: translateY(0);
}

@media (max-width: 1200px) {
  .hero-content {
    grid-template-columns: minmax(300px, 500px) minmax(260px, 1fr);
  }

  .phone-stage {
    margin-right: 48px;
  }

  .phone-stage > img {
    width: min(720px, 54vw);
    transform: scale(1.34);
  }

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

@media (max-width: 980px) {
  :root {
    --page-gutter: 22px;
    --brand-width: 84px;
    --header-gap: 16px;
    --hero-copy-offset: 0px;
    --hero-nav-gap: 0px;
  }

  .site-header {
    grid-template-columns: auto 1fr auto;
    gap: 16px;
    padding: 14px 22px;
    background: rgba(255, 255, 255, 0.9);
    backdrop-filter: blur(14px);
  }

  .brand {
    width: 84px;
  }

  .menu-toggle {
    display: inline-flex;
    justify-self: end;
    grid-column: 3;
  }

  .nav {
    position: fixed;
    left: 16px;
    right: 16px;
    top: 74px;
    display: grid;
    gap: 6px;
    padding: 14px;
    white-space: normal;
    background: rgba(255, 255, 255, 0.96);
    border: 1px solid var(--line);
    border-radius: 8px;
    box-shadow: var(--shadow);
    opacity: 0;
    pointer-events: none;
    transform: translateY(-12px);
    transition: opacity 180ms ease, transform 180ms ease;
  }

  .nav.is-open {
    opacity: 1;
    pointer-events: auto;
    transform: translateY(0);
  }

  .nav a {
    padding: 10px 8px;
  }

  .platform-shortcuts-wrap,
  .platform-shortcuts {
    display: none;
  }

  .hero,
  .hero-content {
    min-height: auto;
  }

  .hero-content {
    grid-template-columns: minmax(0, 1fr);
    gap: 24px;
    padding: 112px 22px 0;
  }

  .hero-copy {
    max-width: 560px;
  }

  .hero h1 {
    font-size: 38px;
  }

  .hero-subtitle {
    font-size: 24px;
    margin-bottom: 18px;
  }

  .hero-text {
    font-size: 17px;
  }

  .phone-stage {
    justify-self: center;
    align-self: end;
    width: min(520px, 100%);
    margin: 0 auto;
  }

  .phone-stage > img {
    width: 100%;
    transform: none;
  }

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

  .feedback-wrap {
    grid-template-columns: 44px minmax(0, 1fr) 44px;
    gap: 14px;
  }

  .feedback-arrow {
    width: 44px;
    height: 44px;
  }

  .site-footer {
    grid-template-columns: 1fr 1fr;
    gap: 36px;
  }
}

@media (max-width: 640px) {
  .site-header {
    padding: 12px 18px;
  }

  .nav {
    left: 12px;
    right: 12px;
    top: 68px;
  }

  .hero-bg {
    background:
      linear-gradient(180deg, rgba(255, 255, 255, 0.78) 0%, rgba(255, 255, 255, 0.52) 45%, rgba(247, 248, 245, 0.08) 100%),
      url("./assets/course-bg.png") center bottom / cover no-repeat;
  }

  .hero-content {
    padding: 94px 18px 0;
  }

  .hero h1 {
    font-size: 32px;
  }

  .hero-subtitle {
    font-size: 21px;
  }

  .hero-text {
    max-width: 340px;
    font-size: 16px;
  }

  .primary-cta {
    min-width: 136px;
    min-height: 48px;
    font-size: 16px;
  }

  .phone-stage {
    width: min(360px, 96vw);
  }

  .section,
  .feedback-band,
  .download-section {
    padding: 48px 18px;
  }

  .section-heading h2 {
    margin-bottom: 34px;
    font-size: 24px;
  }

  .feature-grid,
  .download-grid,
  .site-footer {
    grid-template-columns: 1fr;
  }

  .feature-grid {
    gap: 18px;
  }

  .feature-card {
    min-height: 0;
    padding: 20px;
  }

  .feature-card img {
    height: 128px;
  }

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

  .feedback-arrow {
    display: none;
  }

  .feedback-grid {
    gap: 16px;
    padding-bottom: 10px;
    margin-bottom: -10px;
    scroll-snap-type: x mandatory;
  }

  .feedback-grid .feedback-card {
    flex-basis: 86%;
    scroll-snap-align: center;
  }

  .feedback-card {
    min-height: 220px;
    padding: 22px;
  }

  blockquote {
    -webkit-line-clamp: 6;
  }

  .download-card {
    grid-template-columns: 44px 1fr 58px;
    gap: 12px;
    min-height: 84px;
  }

  .download-card:hover .download-qr-img,
  .download-card:focus-visible .download-qr-img {
    transform: scale(1.5);
  }

  .site-footer {
    gap: 28px;
    padding: 38px 24px 30px;
  }

  .footer-brand {
    align-items: flex-start;
    flex-direction: column;
  }

  .social-qr {
    left: 0;
    transform: translateY(8px) scale(0.86);
    transform-origin: left bottom;
  }

  .social-qr::after {
    left: 24px;
  }

  .social:hover .social-qr,
  .social:focus-visible .social-qr {
    transform: translateY(0) scale(1);
  }
}

@media (max-width: 420px) {
  :root {
    --brand-width: 78px;
  }

  .site-header {
    padding-inline: 14px;
  }

  .hero-content {
    padding-inline: 16px;
  }

  .hero h1 {
    font-size: 29px;
  }

  .hero-subtitle {
    font-size: 19px;
  }

  .hero-text {
    max-width: none;
    font-size: 15px;
  }

  .phone-stage {
    width: min(310px, 94vw);
  }

  .feedback-grid .feedback-card {
    flex-basis: 92%;
  }

  .download-card {
    grid-template-columns: 40px minmax(0, 1fr) 52px;
    padding: 12px;
  }

  .download-card strong {
    font-size: 15px;
  }

  .download-card small {
    font-size: 11px;
  }

  .store-icon-img {
    width: 40px;
    height: 40px;
  }

  .site-footer {
    padding-inline: 18px;
  }
}

@media (hover: none), (pointer: coarse) {
  .download-card:hover .download-qr-img,
  .download-card:focus-visible .download-qr-img {
    transform: none;
    box-shadow: none;
  }
}

@media (prefers-reduced-motion: reduce) {
  *,
  *::before,
  *::after {
    animation-duration: 1ms !important;
    scroll-behavior: auto !important;
    transition-duration: 1ms !important;
  }
}