:root {
  --paper: #f2eddf;
  --paper-light: #faf7ee;
  --ink: #17231d;
  --ink-soft: #4d5a52;
  --jade: #0f6d5f;
  --jade-dark: #084a41;
  --vermillion: #df563d;
  --line: rgba(23, 35, 29, 0.18);
  --serif: "Iowan Old Style", "Baskerville", "Songti SC", "STSong", serif;
  --sans: "Avenir Next", Avenir, "PingFang SC", "Microsoft YaHei", sans-serif;
}

* {
  box-sizing: border-box;
}

html {
  background: var(--paper);
  color: var(--ink);
  scroll-behavior: smooth;
}

body {
  margin: 0;
  min-width: 320px;
  min-height: 100vh;
  overflow-x: hidden;
  font-family: var(--sans);
  background:
    radial-gradient(circle at 12% 8%, rgba(255, 255, 255, 0.9), transparent 28%),
    linear-gradient(135deg, var(--paper-light) 0%, var(--paper) 62%, #e7e4d8 100%);
}

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

.paper-noise {
  position: fixed;
  inset: 0;
  pointer-events: none;
  opacity: 0.24;
  z-index: 20;
  background-image:
    repeating-linear-gradient(0deg, transparent 0 3px, rgba(23, 35, 29, 0.018) 3px 4px),
    repeating-linear-gradient(90deg, transparent 0 5px, rgba(255, 255, 255, 0.12) 5px 6px);
  mix-blend-mode: multiply;
}

.landing-shell {
  width: min(1540px, calc(100% - 64px));
  margin: 0 auto;
}

.landing-header {
  min-height: 94px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 32px;
  border-bottom: 1px solid var(--line);
  animation: revealDown 700ms cubic-bezier(0.22, 1, 0.36, 1) both;
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: 12px;
}

.brand-mark {
  width: 38px;
  height: 38px;
  display: grid;
  place-items: center;
  background: var(--ink);
  color: var(--paper-light);
  font-family: var(--serif);
  font-size: 24px;
  line-height: 1;
}

.brand-word {
  font-size: 17px;
  font-weight: 800;
  letter-spacing: 0.13em;
}

.brand-word span {
  color: var(--jade);
}

.top-nav {
  display: flex;
  align-items: center;
  gap: 28px;
  font-size: 13px;
  font-weight: 700;
  letter-spacing: 0.04em;
}

.nav-link {
  position: relative;
  padding: 10px 0;
}

.nav-link::after {
  content: "";
  position: absolute;
  left: 0;
  right: 100%;
  bottom: 4px;
  height: 1px;
  background: var(--jade);
  transition: right 180ms ease;
}

.nav-link:hover::after,
.nav-link:focus-visible::after {
  right: 0;
}

.nav-login {
  min-height: 42px;
  display: inline-flex;
  align-items: center;
  gap: 24px;
  padding: 0 8px 0 18px;
  border: 1px solid var(--ink);
  transition: background 180ms ease, color 180ms ease, transform 180ms ease;
}

.nav-login .arrow {
  width: 28px;
  height: 28px;
  display: grid;
  place-items: center;
  background: var(--ink);
  color: var(--paper-light);
  font-size: 14px;
  transition: transform 180ms ease;
}

.nav-login:hover,
.nav-login:focus-visible {
  background: var(--ink);
  color: var(--paper-light);
  transform: translateY(-2px);
}

.nav-login:hover .arrow,
.nav-login:focus-visible .arrow {
  background: var(--vermillion);
  transform: rotate(7deg);
}

.hero {
  min-height: min(790px, calc(100vh - 94px));
  display: grid;
  grid-template-columns: minmax(0, 0.88fr) minmax(560px, 1.12fr);
  align-items: center;
  gap: clamp(40px, 6vw, 110px);
  padding: 56px 0 72px;
}

.hero-copy {
  position: relative;
  z-index: 2;
  padding-left: clamp(0px, 3vw, 44px);
}

.eyebrow {
  display: flex;
  align-items: center;
  gap: 12px;
  margin: 0 0 30px;
  color: var(--jade);
  font-size: 11px;
  font-weight: 800;
  letter-spacing: 0.2em;
  text-transform: uppercase;
  animation: revealUp 700ms 120ms cubic-bezier(0.22, 1, 0.36, 1) both;
}

.eyebrow span {
  width: 34px;
  height: 2px;
  background: var(--vermillion);
}

h1 {
  max-width: 700px;
  margin: 0;
  font-family: var(--serif);
  font-size: clamp(64px, 7.2vw, 118px);
  font-weight: 500;
  letter-spacing: -0.065em;
  line-height: 0.82;
  animation: revealUp 800ms 190ms cubic-bezier(0.22, 1, 0.36, 1) both;
}

h1 em {
  display: block;
  margin-top: 0.16em;
  color: var(--jade);
  font-weight: 400;
}

.chinese-line {
  display: flex;
  align-items: center;
  gap: 17px;
  margin-top: 36px;
  color: var(--ink);
  font-family: "Songti SC", "STSong", var(--serif);
  font-size: clamp(17px, 1.5vw, 24px);
  letter-spacing: 0.22em;
  animation: revealUp 700ms 280ms cubic-bezier(0.22, 1, 0.36, 1) both;
}

.chinese-line i {
  width: 6px;
  height: 6px;
  background: var(--vermillion);
  transform: rotate(45deg);
}

.hero-intro {
  max-width: 570px;
  margin: 36px 0 0;
  color: var(--ink-soft);
  font-family: var(--serif);
  font-size: clamp(17px, 1.3vw, 21px);
  line-height: 1.65;
  animation: revealUp 700ms 360ms cubic-bezier(0.22, 1, 0.36, 1) both;
}

.hero-actions {
  display: flex;
  align-items: center;
  gap: 30px;
  margin-top: 42px;
  animation: revealUp 700ms 440ms cubic-bezier(0.22, 1, 0.36, 1) both;
}

.primary-action {
  min-width: 206px;
  min-height: 54px;
  display: inline-flex;
  align-items: center;
  justify-content: space-between;
  gap: 24px;
  padding: 0 18px 0 22px;
  background: var(--ink);
  color: var(--paper-light);
  font-size: 13px;
  font-weight: 750;
  transition: background 180ms ease, transform 180ms ease;
}

.primary-action:hover,
.primary-action:focus-visible {
  background: var(--jade);
  transform: translateY(-3px);
}

.text-action {
  display: inline-flex;
  align-items: center;
  gap: 9px;
  padding: 10px 0;
  border-bottom: 1px solid var(--ink);
  font-size: 13px;
  font-weight: 750;
  transition: color 180ms ease, border-color 180ms ease;
}

.text-action:hover,
.text-action:focus-visible {
  color: var(--jade);
  border-color: var(--jade);
}

.hero-art {
  position: relative;
  min-height: 650px;
  overflow: hidden;
  border-left: 1px solid var(--line);
  border-right: 1px solid var(--line);
  background:
    linear-gradient(rgba(250, 247, 238, 0.76), rgba(230, 235, 225, 0.48)),
    radial-gradient(circle at 68% 25%, rgba(15, 109, 95, 0.18), transparent 34%);
  animation: revealArt 900ms 220ms cubic-bezier(0.22, 1, 0.36, 1) both;
}

.art-grid {
  position: absolute;
  inset: 0;
  opacity: 0.5;
  background-image:
    linear-gradient(to right, var(--line) 1px, transparent 1px),
    linear-gradient(to bottom, var(--line) 1px, transparent 1px);
  background-size: 82px 82px;
  -webkit-mask-image: linear-gradient(to bottom, black, transparent 88%);
  mask-image: linear-gradient(to bottom, black, transparent 88%);
}

.sun {
  position: absolute;
  top: 76px;
  right: 70px;
  width: 128px;
  height: 128px;
  border-radius: 50%;
  background: var(--vermillion);
  box-shadow: 0 0 0 18px rgba(223, 86, 61, 0.07);
  animation: sunBreath 5s ease-in-out infinite;
}

.ink-paths {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
  overflow: visible;
}

.path {
  fill: none;
  stroke: var(--jade-dark);
  stroke-linecap: round;
  stroke-width: 2;
  vector-effect: non-scaling-stroke;
  opacity: 0.7;
  stroke-dasharray: 1100;
  stroke-dashoffset: 1100;
  animation: drawPath 2.2s 650ms ease-out forwards;
}

.path-two {
  stroke-width: 1.2;
  opacity: 0.42;
  animation-delay: 760ms;
}

.path-three {
  stroke: var(--vermillion);
  stroke-width: 1;
  opacity: 0.46;
  animation-delay: 880ms;
}

.orbit {
  position: absolute;
  border: 1px solid rgba(15, 109, 95, 0.28);
  border-radius: 50%;
}

.orbit::after {
  content: "";
  position: absolute;
  width: 8px;
  height: 8px;
  border-radius: 50%;
  background: var(--jade);
}

.orbit-one {
  top: 31px;
  right: 21px;
  width: 240px;
  height: 240px;
  animation: slowSpin 18s linear infinite;
}

.orbit-one::after {
  top: 36px;
  left: 27px;
}

.orbit-two {
  top: 14px;
  right: 4px;
  width: 274px;
  height: 274px;
  border-style: dashed;
  animation: slowSpin 28s linear infinite reverse;
}

.orbit-two::after {
  right: 31px;
  bottom: 51px;
  background: var(--vermillion);
}

.thought-card {
  position: absolute;
  width: min(330px, 52%);
  display: grid;
  grid-template-columns: 36px 1fr;
  gap: 14px;
  padding: 17px 18px;
  border: 1px solid rgba(15, 109, 95, 0.32);
  background: rgba(250, 247, 238, 0.83);
  box-shadow: 12px 14px 0 rgba(15, 109, 95, 0.08);
  backdrop-filter: blur(8px);
  -webkit-backdrop-filter: blur(8px);
}

.thought-card strong {
  display: block;
  font-family: var(--serif);
  font-size: 20px;
  font-weight: 600;
}

.thought-card p {
  margin: 3px 0 0;
  color: var(--ink-soft);
  font-size: 12px;
  line-height: 1.45;
}

.card-index {
  color: var(--vermillion);
  font-size: 10px;
  font-weight: 800;
  letter-spacing: 0.08em;
}

.card-context {
  top: 162px;
  left: 7%;
  animation: floatCard 6s 100ms ease-in-out infinite, revealUp 700ms 540ms both;
}

.card-create {
  top: 302px;
  right: 6%;
  animation: floatCard 7s 800ms ease-in-out infinite, revealUp 700ms 660ms both;
}

.card-learn {
  top: 445px;
  left: 17%;
  animation: floatCard 6.5s 1400ms ease-in-out infinite, revealUp 700ms 780ms both;
}

.seal {
  position: absolute;
  left: 38px;
  bottom: 30px;
  width: 48px;
  height: 48px;
  display: grid;
  grid-template-columns: 1fr 1fr;
  place-items: center;
  padding: 5px;
  border: 2px solid var(--vermillion);
  color: var(--vermillion);
  font-family: "Songti SC", "STSong", serif;
  font-size: 13px;
  line-height: 1;
  transform: rotate(-4deg);
}

.art-caption {
  position: absolute;
  right: 38px;
  bottom: 27px;
  margin: 0;
  color: var(--jade-dark);
  font-family: var(--serif);
  font-size: 17px;
  font-style: italic;
  line-height: 1.35;
  text-align: right;
}

.principles {
  border-top: 1px solid var(--ink);
  padding: 28px 0 78px;
}

.principles-label {
  margin: 0 0 56px;
  color: var(--jade);
  font-size: 11px;
  font-weight: 800;
  letter-spacing: 0.18em;
  text-transform: uppercase;
}

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

.principles-grid article {
  min-height: 220px;
  padding: 0 clamp(24px, 3.5vw, 56px);
  border-left: 1px solid var(--line);
}

.principles-grid article:first-child {
  padding-left: 0;
  border-left: 0;
}

.principles-grid article:last-child {
  padding-right: 0;
}

.principles-grid span {
  color: var(--vermillion);
  font-size: 10px;
  font-weight: 800;
}

.principles-grid h2 {
  margin: 24px 0 18px;
  font-family: var(--serif);
  font-size: clamp(26px, 2.2vw, 38px);
  font-weight: 500;
  line-height: 1.08;
}

.principles-grid p {
  max-width: 390px;
  margin: 0;
  color: var(--ink-soft);
  font-size: 14px;
  line-height: 1.7;
}

.landing-footer {
  min-height: 100px;
  display: grid;
  grid-template-columns: 1fr auto 1fr;
  align-items: center;
  gap: 24px;
  border-top: 1px solid var(--line);
  color: var(--ink-soft);
  font-size: 12px;
}

.landing-footer > p:first-child {
  color: var(--ink);
  font-weight: 800;
  letter-spacing: 0.08em;
}

.footer-motto {
  font-family: "Songti SC", "STSong", var(--serif);
  letter-spacing: 0.16em;
}

.landing-footer div {
  display: flex;
  justify-content: flex-end;
  gap: 24px;
  font-weight: 700;
}

.landing-footer a:hover,
.landing-footer a:focus-visible {
  color: var(--jade);
}

a:focus-visible {
  outline: 2px solid var(--vermillion);
  outline-offset: 4px;
}

@keyframes revealDown {
  from { opacity: 0; transform: translateY(-18px); }
  to { opacity: 1; transform: translateY(0); }
}

@keyframes revealUp {
  from { opacity: 0; transform: translateY(28px); }
  to { opacity: 1; transform: translateY(0); }
}

@keyframes revealArt {
  from { opacity: 0; transform: translateX(34px); }
  to { opacity: 1; transform: translateX(0); }
}

@keyframes drawPath {
  to { stroke-dashoffset: 0; }
}

@keyframes sunBreath {
  0%, 100% { transform: scale(1); box-shadow: 0 0 0 18px rgba(223, 86, 61, 0.07); }
  50% { transform: scale(1.035); box-shadow: 0 0 0 28px rgba(223, 86, 61, 0.035); }
}

@keyframes slowSpin {
  to { transform: rotate(360deg); }
}

@keyframes floatCard {
  0%, 100% { margin-top: 0; }
  50% { margin-top: -8px; }
}

@media (max-width: 1100px) {
  .landing-shell {
    width: min(100% - 40px, 980px);
  }

  .hero {
    grid-template-columns: 1fr;
    gap: 54px;
    padding-top: 72px;
  }

  .hero-copy {
    max-width: 790px;
    padding-left: 0;
  }

  h1 {
    font-size: clamp(70px, 12vw, 118px);
  }

  .hero-art {
    width: 100%;
    min-height: 610px;
  }
}

@media (max-width: 700px) {
  .landing-shell {
    width: calc(100% - 30px);
  }

  .landing-header {
    min-height: 74px;
  }

  .brand {
    gap: 9px;
  }

  .brand-mark {
    width: 32px;
    height: 32px;
    font-size: 20px;
  }

  .brand-word {
    font-size: 14px;
  }

  .top-nav {
    gap: 14px;
  }

  .nav-link {
    font-size: 12px;
  }

  .nav-login {
    min-height: 36px;
    padding-left: 12px;
    gap: 9px;
    font-size: 12px;
  }

  .nav-login .arrow {
    width: 24px;
    height: 24px;
  }

  .hero {
    min-height: auto;
    gap: 46px;
    padding: 56px 0 52px;
  }

  .eyebrow {
    margin-bottom: 24px;
    font-size: 9px;
  }

  h1 {
    font-size: clamp(56px, 18vw, 82px);
    line-height: 0.86;
  }

  .chinese-line {
    flex-wrap: wrap;
    gap: 12px;
    margin-top: 29px;
    font-size: 17px;
  }

  .hero-intro {
    margin-top: 27px;
    font-size: 17px;
  }

  .hero-actions {
    align-items: stretch;
    flex-direction: column;
    gap: 15px;
    margin-top: 32px;
  }

  .primary-action {
    width: 100%;
  }

  .text-action {
    align-self: flex-start;
  }

  .hero-art {
    min-height: 540px;
    border-right: 0;
  }

  .sun {
    top: 50px;
    right: 32px;
    width: 92px;
    height: 92px;
  }

  .orbit-one {
    top: 17px;
    right: -1px;
    width: 174px;
    height: 174px;
  }

  .orbit-two {
    top: 2px;
    right: -16px;
    width: 204px;
    height: 204px;
  }

  .thought-card {
    width: 78%;
    grid-template-columns: 28px 1fr;
    padding: 14px;
  }

  .thought-card strong {
    font-size: 18px;
  }

  .card-context {
    top: 155px;
    left: 6%;
  }

  .card-create {
    top: 287px;
    right: 5%;
  }

  .card-learn {
    top: 414px;
    left: 10%;
  }

  .seal {
    left: 20px;
    bottom: 18px;
  }

  .art-caption {
    right: 18px;
    bottom: 18px;
    font-size: 15px;
  }

  .principles {
    padding-bottom: 50px;
  }

  .principles-label {
    margin-bottom: 34px;
  }

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

  .principles-grid article,
  .principles-grid article:first-child,
  .principles-grid article:last-child {
    min-height: 0;
    padding: 26px 0 32px;
    border-left: 0;
    border-top: 1px solid var(--line);
  }

  .principles-grid article:first-child {
    border-top: 0;
    padding-top: 0;
  }

  .landing-footer {
    min-height: 140px;
    grid-template-columns: 1fr auto;
    gap: 10px 20px;
    padding: 24px 0;
  }

  .footer-motto {
    grid-column: 1 / -1;
    grid-row: 2;
    margin: 0;
  }
}

@media (max-width: 430px) {
  .brand-word {
    display: none;
  }

  .top-nav {
    gap: 12px;
  }

  .nav-link {
    font-size: 11px;
  }

  .nav-login {
    padding-left: 10px;
    font-size: 11px;
  }

  h1 {
    font-size: clamp(52px, 19vw, 72px);
  }
}

@media (prefers-reduced-motion: reduce) {
  *,
  *::before,
  *::after {
    scroll-behavior: auto !important;
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
  }
}