/* =========================================================
   ROOT
========================================================= */

:root {
  --black: #000;
  --surface: #0d0d11;
  --surface-2: #111116;

  --white: #f5f5f7;
  --text: #ededed;
  --muted: #86868b;
  --muted-2: #5d5d63;

  --blue: #2997ff;
  --blue-soft: rgba(41, 151, 255, .10);

  --green: #30d158;

  --border: rgba(255, 255, 255, .085);

  --container: 960px;

  --font:
    -apple-system,
    BlinkMacSystemFont,
    "SF Pro Display",
    "SF Pro Text",
    "Helvetica Neue",
    "PingFang SC",
    "Microsoft YaHei",
    sans-serif;
}


/* =========================================================
   RESET
========================================================= */

* {
  box-sizing: border-box;
}

html {
  width: 100%;
  min-height: 100%;
  background: #000;
}

body {
  width: 100%;
  min-height: 100vh;

  margin: 0;
  padding: 0;

  overflow-x: hidden;

  background: #000;
  color: var(--white);

  font-family: var(--font);

  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
}

a {
  color: inherit;
}

button {
  font-family: inherit;
}


/* =========================================================
   HEADER
========================================================= */

.site-header {
  position: fixed;

  top: 0;
  left: 0;
  right: 0;

  z-index: 100;

  height: 70px;

  padding: 0 40px;

  display: flex;
  align-items: center;
  justify-content: space-between;

  background: rgba(0, 0, 0, .72);

  border-bottom: 1px solid rgba(255, 255, 255, .055);

  backdrop-filter: blur(20px);
  -webkit-backdrop-filter: blur(20px);
}


/* =========================================================
   BRAND
========================================================= */

.brand-block {
  display: flex;
  flex-direction: column;

  align-items: flex-start;

  gap: 4px;

  line-height: 1;
  text-decoration: none;
}

.brand-name {
  color: #fff;

  font-size: 15px;
  font-weight: 700;

  letter-spacing: .045em;
}

.brand-subtitle {
  color: #77777d;

  font-size: 9px;
  font-weight: 400;

  letter-spacing: .1em;
}


/* =========================================================
   SOCIAL
========================================================= */

.social-links {
  display: flex;
  align-items: center;

  gap: 18px;
}

.social-icon {
  width: 19px;
  height: 19px;

  display: flex;
  align-items: center;
  justify-content: center;

  color: rgba(255, 255, 255, .48);

  text-decoration: none;

  transition:
    color .25s ease,
    transform .25s ease;
}

.social-icon svg {
  width: 18px;
  height: 18px;

  display: block;

  fill: currentColor;
}

.social-icon:hover {
  color: #fff;
  transform: translateY(-2px);
}


/* =========================================================
   STORY
========================================================= */

.story-section {
  position: fixed;

  inset: 0;

  z-index: 20;

  display: flex;

  align-items: center;
  justify-content: center;

  padding:
    90px 20px 70px;

  transition:
    opacity .9s cubic-bezier(.16, 1, .3, 1),
    transform .9s cubic-bezier(.16, 1, .3, 1);
}

.story-section.fade-out {
  opacity: 0;

  transform: scale(.97);

  pointer-events: none;
}


/* =========================================================
   STORY CARD
========================================================= */

.story-stage {
  width: min(720px, 100%);

  display: flex;
  flex-direction: column;
  align-items: stretch;
}


.story-card {
  position: relative;

  width: 100%;

  min-height: 390px;

  padding: 42px 46px;

  display: flex;
  flex-direction: column;
  justify-content: space-between;

  background:
    rgba(16, 16, 20, .86);

  border: 1px solid var(--border);

  border-radius: 20px;

  box-shadow:
    0 30px 80px rgba(0, 0, 0, .75);

  backdrop-filter: blur(28px);
  -webkit-backdrop-filter: blur(28px);
}


.story-meta {
  display: flex;
  align-items: center;

  gap: 12px;

  color: var(--muted);

  font-size: 11px;
  font-weight: 600;

  letter-spacing: .1em;
}

.story-year-label {
  color: var(--green);

  font-weight: 600;
}

.story-meta-line {
  width: 24px;
  height: 1px;

  background: rgba(255, 255, 255, .18);
}


.story-kicker {
  margin: 20px 0 0;

  color: var(--blue);

  font-size: 13px;
  font-weight: 600;

  letter-spacing: .03em;

  transition: opacity .3s ease;
}


.story-text-wrapper {
  min-height: 135px;

  margin-top: 14px;
}

.story-stage-text {
  color: #ededed;

  font-size: 23px;
  line-height: 1.7;

  font-weight: 500;

  letter-spacing: .005em;
}

.typewriter-cursor {
  display: inline-block;

  width: 2px;
  height: 22px;

  margin-left: 4px;

  vertical-align: -2px;

  background: var(--blue);

  animation:
    blink .8s steps(1) infinite;
}

@keyframes blink {

  0%,
  45% {
    opacity: 1;
  }

  46%,
  100% {
    opacity: 0;
  }

}


.story-footnote {
  margin: 20px 0 0;

  color: var(--muted);

  font-size: 12px;

  line-height: 1.6;

  transition: opacity .3s ease;
}


.story-timeline {
  width: calc(100% - 52px);

  margin: 20px auto 0;
}


.story-timeline-meta {
  display: flex;
  align-items: center;
  justify-content: space-between;

  margin-bottom: 9px;

  color: #5f5f65;

  font-size: 9px;
  line-height: 1;
}


#story-timeline-count {
  font-variant-numeric: tabular-nums;
}


.story-timeline-track {
  position: relative;

  height: 20px;
}


.story-timeline-line {
  position: absolute;

  left: 10px;
  right: 10px;
  top: 50%;

  height: 1px;

  overflow: hidden;

  background: rgba(255, 255, 255, .11);

  transform: translateY(-50%);
}


.story-timeline-fill {
  display: block;

  width: 0;
  height: 100%;

  background: var(--blue);

  transition: width .45s cubic-bezier(.16, 1, .3, 1);
}


.story-timeline-markers {
  position: absolute;

  inset: 0;

  display: flex;
  align-items: center;
  justify-content: space-between;
}


.story-timeline-marker {
  width: 20px;
  height: 20px;

  flex: 0 0 20px;

  padding: 0;

  display: grid;
  place-items: center;

  appearance: none;

  background: transparent;

  border: 0;

  cursor: pointer;
}


.story-timeline-marker::before {
  content: "";

  width: 6px;
  height: 6px;

  background: #34343a;

  border: 1px solid #5a5a61;
  border-radius: 50%;

  transition:
    transform .3s ease,
    background .3s ease,
    border-color .3s ease,
    box-shadow .3s ease;
}


.story-timeline-marker.complete::before {
  background: var(--blue);
  border-color: var(--blue);
}


.story-timeline-marker.current::before {
  background: var(--green);
  border-color: rgba(255, 255, 255, .72);

  transform: scale(1.5);

  box-shadow: 0 0 0 3px rgba(48, 209, 88, .12);
}


.story-timeline-marker:not(.current):hover::before {
  background: var(--blue);
  border-color: rgba(255, 255, 255, .7);

  transform: scale(1.35);
}


.story-timeline-marker:focus-visible {
  outline: none;
}


.story-timeline-marker:focus-visible::before {
  border-color: #fff;

  box-shadow: 0 0 0 4px rgba(41, 151, 255, .2);
}


/* =========================================================
   ENTER HOME BUTTON
   居中
========================================================= */

.skip-btn {
  margin: 12px auto 0;

  display: flex;
  align-items: center;
  justify-content: center;

  gap: 6px;

  padding: 8px 14px;

  border: 0;

  background: transparent;

  color: #77777d;

  font-size: 12px;

  white-space: nowrap;

  cursor: pointer;

  transition:
    color .25s ease,
    transform .25s ease;
}

.skip-btn:hover {
  color: #fff;

  transform: translateY(-2px);
}


/* =========================================================
   LANDING
========================================================= */

.landing-section {
  position: relative;

  width: 100%;

  height: 100vh;
  min-height: 100svh;

  padding:
    88px 0 44px;

  display: flex;

  align-items: center;
  justify-content: center;

  overflow: hidden;

  opacity: 0;
  visibility: hidden;

  transform: translateY(24px);

  transition:
    opacity 1s cubic-bezier(.16, 1, .3, 1),
    transform 1s cubic-bezier(.16, 1, .3, 1);
}

.landing-section.active {
  opacity: 1;
  visibility: visible;

  transform: translateY(0);
}


/* =========================================================
   MAIN CONTAINER
   960px
========================================================= */

.landing-container {
  width: min(var(--container),
      calc(100% - 40px));

  margin: 0 auto;

  text-align: center;
}


/* =========================================================
   TITLE
========================================================= */

.badge-tag {
  display: inline-flex;
  align-items: center;

  padding: 6px 14px;

  margin-bottom: 17px;

  color: #77777d;

  font-size: 10px;

  letter-spacing: .07em;

  background: rgba(255, 255, 255, .035);

  border: 1px solid rgba(255, 255, 255, .075);

  border-radius: 30px;
}


.landing-title {
  margin: 0 0 15px;

  font-size:
    clamp(38px,
      5.2vw,
      62px);

  line-height: 1.12;

  font-weight: 700;

  letter-spacing: -.04em;

  background:
    linear-gradient(180deg,
      #fff 0%,
      #a5a5aa 100%);

  -webkit-background-clip: text;
  background-clip: text;

  -webkit-text-fill-color: transparent;
}

.landing-title span {
  background:
    linear-gradient(135deg,
      #2997ff 0%,
      #70b8ff 100%);

  -webkit-background-clip: text;
  background-clip: text;

  -webkit-text-fill-color: transparent;
}


.landing-subtitle {
  max-width: 650px;

  margin:
    0 auto 16px;

  color: var(--muted);

  font-size: 13px;

  line-height: 1.7;
}


.landing-quote {
  margin: 0 0 7px;

  color: rgba(255, 255, 255, .34);

  font-size: 10px;

  letter-spacing: .05em;
}


.replay-story-link {
  display: inline-block;

  margin-bottom: 15px;

  color: #65656b;

  font-size: 10px;

  text-decoration: none;

  cursor: pointer;

  transition: color .25s ease;
}

.replay-story-link:hover {
  color: var(--blue);
}


/* =========================================================
   TECHNOLOGY WALL
   缩窄
========================================================= */

.tech-wall {
  position: relative;

  width: min(900px,
      100%);

  margin:
    5px auto 18px;

  overflow: hidden;

  mask-image:
    linear-gradient(to right,
      transparent 0%,
      #000 8%,
      #000 92%,
      transparent 100%);

  -webkit-mask-image:
    linear-gradient(to right,
      transparent 0%,
      #000 8%,
      #000 92%,
      transparent 100%);
}


.tech-row {
  display: flex;

  width: max-content;

  gap: 9px;

  margin: 5px 0;

  will-change: transform;
}


.tech-row.left {
  animation:
    tech-left 34s linear infinite;
}

.tech-row.right {
  animation:
    tech-right 38s linear infinite;
}


@keyframes tech-left {

  from {
    transform: translateX(0);
  }

  to {
    transform: translateX(-50%);
  }

}


@keyframes tech-right {

  from {
    transform: translateX(-50%);
  }

  to {
    transform: translateX(0);
  }

}


.tech-item {
  width: 125px;
  height: 43px;

  flex-shrink: 0;

  display: flex;

  align-items: center;
  justify-content: center;

  gap: 7px;

  color: rgba(255, 255, 255, .40);

  background:
    rgba(255, 255, 255, .025);

  border:
    1px solid rgba(255, 255, 255, .07);

  border-radius: 10px;

  transition:
    color .3s ease,
    background .3s ease,
    border-color .3s ease,
    transform .3s ease;
}


.tech-item svg {
  width: 17px;
  height: 17px;

  flex-shrink: 0;

  fill: currentColor;

  opacity: .9;
}


.tech-item span {
  font-size: 10px;

  font-weight: 600;

  white-space: nowrap;
}


.tech-item:hover {
  color: #fff;

  background:
    rgba(255, 255, 255, .06);

  border-color:
    rgba(255, 255, 255, .16);

  transform: translateY(-2px);
}


.tech-wall:hover .tech-row {
  animation-play-state: paused;
}


/* =========================================================
   FEATURES
   缩窄 + 主次更明显
========================================================= */

.features-grid {
  width: min(900px,
      100%);

  margin:
    0 auto 13px;

  display: grid;

  grid-template-columns:
    repeat(4, 1fr);

  gap: 10px;
}


.feature-card {
  min-width: 0;

  padding:
    18px 17px;

  text-align: left;

  background:
    rgba(13, 13, 17, .95);

  border:
    1px solid rgba(255, 255, 255, .08);

  border-radius: 15px;

  transition:
    transform .3s ease,
    border-color .3s ease,
    background .3s ease,
    box-shadow .3s ease;
}


.feature-card:hover {
  transform: translateY(-3px);

  border-color:
    rgba(41, 151, 255, .32);

  background:
    #111117;

  box-shadow:
    0 12px 35px rgba(0, 0, 0, .45);
}


.feature-icon {
  width: 36px;
  height: 36px;

  margin-bottom: 12px;

  display: flex;

  align-items: center;
  justify-content: center;

  color: var(--blue);

  background:
    rgba(41, 151, 255, .09);

  border-radius: 10px;
}


.feature-icon svg {
  width: 19px;
  height: 19px;

  fill: currentColor;
}


.feature-card h3 {
  margin:
    0 0 6px;

  color: var(--text);

  font-size: 13px;

  line-height: 1.4;

  font-weight: 600;
}


.feature-card p {
  margin: 0;

  color: #77777d;

  font-size: 9px;

  line-height: 1.6;
}


/* =========================================================
   GUARANTEES
   跟随主体宽度
========================================================= */

.guarantees-list {
  width: min(900px,
      100%);

  margin:
    0 auto;

  padding:
    0 2px;

  display: grid;

  grid-template-columns:
    repeat(4, 1fr);

  gap: 10px;
}


.guarantee-item {
  display: flex;

  align-items: center;

  justify-content: center;

  gap: 6px;

  min-width: 0;

  color: #66666c;

  font-size: 9px;

  white-space: nowrap;
}


.guarantee-item svg {
  width: 14px;
  height: 14px;

  flex-shrink: 0;

  fill: var(--green);
}


/* =========================================================
   FOOTER
========================================================= */

.site-footer {
  position: fixed;

  left: 0;
  right: 0;
  bottom: 0;

  z-index: 90;

  height: 34px;

  display: flex;

  align-items: center;
  justify-content: center;

  gap: 10px;

  background:
    rgba(0, 0, 0, .82);

  border-top:
    1px solid rgba(255, 255, 255, .04);

  backdrop-filter: blur(10px);
  -webkit-backdrop-filter: blur(10px);

  color: #38383d;

  font-size: 8px;
}

.site-footer a {
  color: #38383d;

  text-decoration: none;
}

.site-footer a:hover {
  color: var(--blue);
}


/* =========================================================
   WECHAT MODAL
========================================================= */

.wechat-modal {
  position: fixed;

  inset: 0;

  z-index: 300;

  display: none;

  align-items: center;
  justify-content: center;

  background:
    rgba(0, 0, 0, .78);

  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
}


.wechat-card {
  width: 250px;

  padding: 24px;

  text-align: center;

  background:
    #151519;

  border:
    1px solid rgba(255, 255, 255, .12);

  border-radius: 18px;

  box-shadow:
    0 25px 70px rgba(0, 0, 0, .8);
}


.wechat-card .wechat-placeholder {
  width: 170px;
  height: 170px;

  margin: 0 auto;

  display: flex;

  align-items: center;
  justify-content: center;

  background: #fff;

  border-radius: 10px;

  color: #111;

  font-size: 12px;
}


.wechat-card p {
  margin:
    14px 0 0;

  color: #77777d;

  font-size: 11px;
}


/* =========================================================
   TABLET
========================================================= */

@media (max-width: 900px) {

  .landing-container {
    width:
      min(760px,
        calc(100% - 32px));
  }


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


  .guarantees-list {
    grid-template-columns:
      repeat(2, 1fr);

    row-gap: 7px;
  }

}


/* =========================================================
   MOBILE
========================================================= */

@media (max-width: 640px) {

  /* Header */

  .site-header {
    height: 60px;

    padding:
      0 18px;
  }


  .brand-name {
    font-size: 13px;
  }


  .brand-subtitle {
    font-size: 7px;
  }


  .social-links {
    gap: 13px;
  }


  .social-icon {
    width: 17px;
    height: 17px;
  }


  .social-icon svg {
    width: 16px;
    height: 16px;
  }


  /* Story */

  .story-section {
    padding:
      76px 15px 70px;
  }


  .story-card {
    width: 100%;

    min-height: 420px;

    padding:
      30px 22px;

    border-radius: 17px;
  }


  .story-stage {
    width: 100%;
  }


  .story-meta {
    font-size: 9px;
  }


  .story-kicker {
    margin-top: 17px;

    font-size: 11px;
  }


  .story-text-wrapper {
    min-height: 180px;
  }


  .story-stage-text {
    font-size: 19px;

    line-height: 1.75;
  }


  .story-footnote {
    font-size: 10px;
  }


  .story-footnote {
    margin-top: 16px;
  }


  .story-timeline {
    width: calc(100% - 24px);

    margin-top: 16px;
  }


  .story-timeline-meta {
    margin-bottom: 8px;

    font-size: 8px;
  }


  .story-timeline-marker {
    width: 18px;
    height: 18px;

    flex-basis: 18px;
  }


  .story-timeline-marker::before {
    width: 5px;
    height: 5px;
  }


  .skip-btn {
    margin-top: 10px;

    font-size: 11px;
  }


  /* Landing */

  .landing-section {
    height: 100svh;
    min-height: 100svh;

    padding:
      74px 0 39px;

    align-items: center;
  }


  .landing-container {
    width:
      calc(100% - 24px);
  }


  .badge-tag {
    margin-bottom: 12px;

    padding:
      5px 11px;

    font-size: 8px;
  }


  .landing-title {
    margin-bottom: 10px;

    font-size: 22px;

    line-height: 1.15;

    letter-spacing: 0;

    white-space: nowrap;
  }


  .landing-subtitle {
    max-width: 350px;

    margin-bottom: 9px;

    font-size: 10px;

    line-height: 1.55;
  }


  .landing-quote {
    font-size: 8px;

    line-height: 1.5;
  }


  .replay-story-link {
    margin-bottom: 7px;

    font-size: 8px;
  }


  /* Logo wall */

  .tech-wall {
    width: 100vw;

    margin:
      4px 0 10px;

    mask-image:
      linear-gradient(to right,
        transparent 0,
        #000 5%,
        #000 95%,
        transparent 100%);

    -webkit-mask-image:
      linear-gradient(to right,
        transparent 0,
        #000 5%,
        #000 95%,
        transparent 100%);
  }


  .tech-row {
    gap: 6px;

    margin: 4px 0;
  }


  .tech-item {
    width: 104px;
    height: 36px;

    gap: 6px;

    border-radius: 9px;
  }


  .tech-item svg {
    width: 14px;
    height: 14px;
  }


  .tech-item span {
    font-size: 8px;
  }


  /* Features */

  .features-grid {
    width: 100%;

    grid-template-columns:
      repeat(2, 1fr);

    gap: 6px;

    margin-bottom: 8px;
  }


  .feature-card {
    padding:
      11px 10px;

    border-radius: 10px;
  }


  .feature-icon {
    width: 27px;
    height: 27px;

    margin-bottom: 7px;

    border-radius: 7px;
  }


  .feature-icon svg {
    width: 14px;
    height: 14px;
  }


  .feature-card h3 {
    margin-bottom: 3px;

    font-size: 10px;
  }


  .feature-card p {
    font-size: 7.5px;

    line-height: 1.45;
  }


  /* Guarantees */

  .guarantees-list {
    width: 100%;

    grid-template-columns:
      repeat(2, 1fr);

    gap: 4px 5px;
  }


  .guarantee-item {
    justify-content: center;

    gap: 4px;

    font-size: 7px;

    text-align: left;
  }


  .guarantee-item svg {
    width: 10px;
    height: 10px;
  }


  /* Footer */

  .site-footer {
    height: 27px;

    font-size: 6.5px;

    gap: 6px;
  }

}


/* =========================================================
   SMALL PHONE
========================================================= */

@media (max-width: 380px) {

  .landing-container {
    width:
      calc(100% - 18px);
  }


  .landing-title {
    font-size: 20px;
  }


  .landing-subtitle {
    font-size: 9px;
  }


  .tech-item {
    width: 96px;

    height: 34px;
  }


  .feature-card {
    padding:
      9px 8px;
  }


  .feature-card h3 {
    font-size: 9px;
  }


  .feature-card p {
    font-size: 7px;
  }


  .guarantee-item {
    font-size: 6.5px;
  }

}


/* =========================================================
   REDUCED MOTION
========================================================= */

@media (prefers-reduced-motion: reduce) {

  .tech-row {
    animation: none !important;
  }

  .typewriter-cursor {
    animation: none;
  }

}