:root {
  --ink: #0f1419;
  --ink-2: #161d24;
  --paper: #e8eef2;
  --dim: #8b98a5;
  --line: rgba(232, 238, 242, 0.12);
  --teal: #2dd4bf;
  --teal-dim: rgba(45, 212, 191, 0.16);
  --amber: #f59e0b;
  --amber-dim: rgba(245, 158, 11, 0.16);
  --signal: #ef4444;
  --signal-dim: rgba(239, 68, 68, 0.16);
  --display: "Figtree", "Noto Sans SC", "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
  --mono: "IBM Plex Mono", Consolas, monospace;
  --max: 720px;
  --ease: cubic-bezier(0.22, 1, 0.36, 1);
}

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

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

body {
  background:
    radial-gradient(ellipse 55% 40% at 8% 12%, rgba(45, 212, 191, 0.07), transparent 55%),
    radial-gradient(ellipse 40% 35% at 92% 8%, rgba(245, 158, 11, 0.05), transparent 50%),
    radial-gradient(ellipse 45% 30% at 70% 88%, rgba(239, 68, 68, 0.04), transparent 55%),
    radial-gradient(ellipse 60% 50% at 50% 50%, rgba(22, 29, 36, 0.9), transparent 70%),
    var(--ink);
  color: var(--paper);
  font-family: var(--display);
  font-size: 15px;
  line-height: 1.55;
  overflow-x: hidden;
}

body.is-splash { overflow: hidden; }

a { color: inherit; text-decoration: none; }
button, input { font: inherit; color: inherit; background: none; border: 0; }
ul, ol { list-style: none; }
img { display: block; max-width: 100%; height: auto; }

.visually-hidden {
  position: absolute;
  width: 1px;
  height: 1px;
  padding: 0;
  margin: -1px;
  overflow: hidden;
  clip: rect(0, 0, 0, 0);
  white-space: nowrap;
  border: 0;
}

/* Splash */
.splash {
  position: fixed;
  inset: 0;
  z-index: 1000;
  display: grid;
  place-content: center;
  gap: 12px;
  background: var(--ink);
  text-align: center;
  transition: opacity 0.45s ease, visibility 0.45s ease;
}
.splash.is-done {
  opacity: 0;
  visibility: hidden;
  pointer-events: none;
}
.splash__brand {
  font-family: var(--display);
  font-weight: 700;
  font-size: clamp(36px, 10vw, 56px);
  letter-spacing: -0.02em;
  animation: brandPulse 1.4s ease-in-out infinite;
}
.splash__line {
  color: var(--teal);
  font-size: 12px;
  letter-spacing: 0.14em;
}
.splash__bar {
  width: min(220px, 60vw);
  height: 2px;
  margin: 4px auto 0;
  background: var(--line);
  overflow: hidden;
  border-radius: 1px;
}
.splash__bar span {
  display: block;
  height: 100%;
  width: 0;
  background: linear-gradient(90deg, var(--teal), rgba(45, 212, 191, 0.5));
  transition: width 0.12s linear;
}
.splash__pct {
  color: var(--dim);
  font-size: 11px;
  letter-spacing: 0.12em;
}

@keyframes brandPulse {
  0%, 100% { opacity: 1; }
  50% { opacity: 0.72; }
}

/* Header */
.top {
  position: sticky;
  top: 0;
  z-index: 80;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 12px;
  padding: calc(10px + env(safe-area-inset-top, 0px)) 16px 10px;
  background: rgba(15, 20, 25, 0.78);
  border-bottom: 1px solid rgba(232, 238, 242, 0.08);
  backdrop-filter: blur(16px);
  -webkit-backdrop-filter: blur(16px);
}
.top__brand {
  font-family: var(--display);
  font-weight: 700;
  font-size: 18px;
  letter-spacing: -0.015em;
}
.top__actions {
  position: relative;
  display: flex;
  align-items: center;
  gap: 8px;
}
.top__lang {
  border: 1px solid var(--line);
  padding: 8px 10px;
  cursor: pointer;
  font-size: 12px;
  letter-spacing: 0.06em;
  border-radius: 6px;
  transition: border-color 0.2s ease, color 0.2s ease, background 0.2s ease;
}
.top__lang:hover {
  border-color: rgba(45, 212, 191, 0.4);
  color: var(--teal);
  background: rgba(45, 212, 191, 0.06);
}
.top__lang-menu {
  position: absolute;
  right: 52px;
  top: calc(100% + 6px);
  min-width: 168px;
  max-height: min(50vh, 360px);
  overflow-x: hidden;
  overflow-y: auto;
  -webkit-overflow-scrolling: touch;
  background: var(--ink-2);
  border: 1px solid var(--line);
  border-radius: 8px;
  z-index: 90;
  box-shadow: 0 12px 32px rgba(0, 0, 0, 0.35);
}
body.is-rtl .top__lang-menu {
  right: auto;
  left: 52px;
}
.top__lang-menu li {
  padding: 10px 12px;
  cursor: pointer;
  font-size: 12px;
}
.top__lang-menu li:hover,
.top__lang-menu li[aria-selected="true"] {
  background: rgba(45, 212, 191, 0.1);
  color: var(--teal);
}
.top__burger {
  display: grid;
  place-content: center;
  gap: 5px;
  width: 42px;
  height: 42px;
  border: 1px solid var(--line);
  border-radius: 6px;
  cursor: pointer;
  transition: border-color 0.2s ease;
}
.top__burger:hover { border-color: rgba(45, 212, 191, 0.35); }
.top__burger span {
  display: block;
  width: 16px;
  height: 2px;
  background: var(--paper);
  transition: transform 0.2s ease, opacity 0.2s ease;
}
.top__burger.is-open span:nth-child(1) { transform: translateY(7px) rotate(45deg); }
.top__burger.is-open span:nth-child(2) { opacity: 0; }
.top__burger.is-open span:nth-child(3) { transform: translateY(-7px) rotate(-45deg); }

.drawer {
  display: none;
  flex-direction: column;
  background: rgba(18, 24, 32, 0.98);
  border-bottom: 1px solid var(--line);
  backdrop-filter: blur(12px);
}
.drawer:not([hidden]) { display: flex; }
.drawer a {
  padding: 14px 16px;
  border-top: 1px solid var(--line);
  font-size: 13px;
  letter-spacing: 0.06em;
  transition: color 0.2s ease, background 0.2s ease;
}
.drawer a:hover {
  color: var(--teal);
  background: rgba(45, 212, 191, 0.05);
}

/* Buttons */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 14px 22px;
  background: linear-gradient(180deg, #5eead4 0%, var(--teal) 100%);
  color: var(--ink);
  font-family: var(--display);
  font-weight: 700;
  font-size: 14px;
  letter-spacing: 0.04em;
  text-transform: uppercase;
  cursor: pointer;
  border: 1px solid var(--teal);
  border-radius: 8px;
  box-shadow: 0 4px 16px rgba(45, 212, 191, 0.22), 0 1px 0 rgba(255, 255, 255, 0.15) inset;
  transition: transform 0.22s var(--ease), background 0.2s ease, box-shadow 0.22s var(--ease);
}
.btn:hover {
  transform: translateY(-2px);
  background: linear-gradient(180deg, #99f6e4 0%, #5eead4 100%);
  box-shadow: 0 8px 24px rgba(45, 212, 191, 0.3), 0 1px 0 rgba(255, 255, 255, 0.12) inset;
}
.btn:active {
  transform: translateY(0);
  box-shadow: 0 2px 8px rgba(45, 212, 191, 0.18);
}
.btn--ghost {
  background: transparent;
  color: var(--teal);
  box-shadow: none;
}
.btn--ghost:hover {
  background: rgba(45, 212, 191, 0.08);
  box-shadow: none;
}

/* Hero */
.hero {
  position: relative;
  min-height: 100svh;
  display: grid;
  align-content: end;
  overflow: hidden;
  border-bottom: 1px solid var(--line);
}
.hero__img {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
  object-fit: cover;
  object-position: center;
  animation: heroDrift 20s ease-in-out infinite alternate;
}
.hero__veil {
  position: absolute;
  inset: 0;
  background:
    radial-gradient(ellipse 45% 40% at 20% 75%, rgba(45, 212, 191, 0.14), transparent 60%),
    radial-gradient(ellipse 30% 25% at 85% 20%, rgba(245, 158, 11, 0.08), transparent 55%),
    linear-gradient(180deg, rgba(15, 20, 25, 0.38) 0%, rgba(15, 20, 25, 0.58) 40%, rgba(15, 20, 25, 0.97) 100%),
    linear-gradient(90deg, rgba(15, 20, 25, 0.78) 0%, transparent 58%);
}
.hero__copy {
  position: relative;
  z-index: 1;
  max-width: 640px;
  padding: 48px 16px 40px;
  animation: rise 0.85s 0.12s var(--ease) both;
}
.hero__brand {
  font-family: var(--display);
  font-weight: 700;
  font-size: clamp(44px, 11vw, 84px);
  line-height: 1;
  letter-spacing: -0.025em;
  margin-bottom: 16px;
  text-shadow: 0 8px 40px rgba(0, 0, 0, 0.45);
}
.hero__brand::after {
  content: "";
  display: block;
  width: 52px;
  height: 3px;
  margin-top: 14px;
  background: linear-gradient(90deg, var(--teal), rgba(245, 158, 11, 0.55), transparent);
  border-radius: 2px;
  animation: barIn 0.7s 0.28s var(--ease) both;
}
.hero h1 {
  font-family: var(--display);
  font-weight: 600;
  font-size: clamp(20px, 3.6vw, 28px);
  line-height: 1.25;
  letter-spacing: -0.015em;
  max-width: 20ch;
  margin-bottom: 12px;
}
.hero__lead {
  color: var(--dim);
  font-size: 14px;
  max-width: 46ch;
}
.hero .btn {
  margin-top: 24px;
  animation: rise 0.7s 0.35s var(--ease) both;
}

@keyframes heroDrift {
  from { transform: scale(1.04) translate3d(0, 0, 0); }
  to { transform: scale(1.09) translate3d(-1.4%, -0.9%, 0); }
}
@keyframes rise {
  from { opacity: 0; transform: translateY(22px); }
  to { opacity: 1; transform: none; }
}
@keyframes barIn {
  from { width: 0; opacity: 0; }
  to { width: 52px; opacity: 1; }
}

/* Shared sections */
.section__k {
  color: var(--teal);
  font-size: 11px;
  letter-spacing: 0.16em;
  margin-bottom: 10px;
}
.section__lead {
  color: var(--dim);
  font-size: 14px;
  max-width: 52ch;
  margin: 8px 0 24px;
}
h2 {
  font-family: var(--display);
  font-weight: 700;
  font-size: clamp(22px, 4vw, 30px);
  line-height: 1.15;
  letter-spacing: -0.02em;
}

.trust,
.check,
.address,
.disclaimer {
  max-width: var(--max);
  margin: 0 auto;
  padding: 48px 16px;
  border-bottom: 1px solid var(--line);
}

.trust__list {
  display: grid;
  gap: 8px;
  margin-top: 22px;
  animation: rise 0.55s 0.1s var(--ease) both;
}
.trust__list li {
  display: grid;
  grid-template-columns: 10px 1fr;
  gap: 12px;
  align-items: start;
  padding: 14px 0;
  border-top: 1px solid rgba(232, 238, 242, 0.08);
  font-size: 14px;
}
.trust__list li::before {
  content: "";
  width: 8px;
  height: 8px;
  margin-top: 6px;
  background: var(--teal);
  border-radius: 1px;
  box-shadow: 0 0 12px rgba(45, 212, 191, 0.35);
}
.trust__list li:last-child { border-bottom: 1px solid rgba(232, 238, 242, 0.08); }

/* Check form */
.check__set {
  border: 0;
  display: grid;
  gap: 8px;
  margin-bottom: 22px;
}
.check__item {
  display: grid;
  grid-template-columns: 22px 1fr;
  gap: 12px;
  align-items: start;
  padding: 15px 14px;
  border: 1px solid rgba(232, 238, 242, 0.1);
  border-radius: 10px;
  background: rgba(22, 29, 36, 0.55);
  cursor: pointer;
  transition:
    border-color 0.22s var(--ease),
    background 0.22s var(--ease),
    transform 0.22s var(--ease),
    box-shadow 0.22s var(--ease);
}
.check__item:hover {
  border-color: rgba(45, 212, 191, 0.4);
  background: rgba(22, 29, 36, 0.85);
  transform: translateY(-1px);
  box-shadow: 0 6px 18px rgba(0, 0, 0, 0.2);
}
.check__item:has(input:checked) {
  border-color: rgba(245, 158, 11, 0.55);
  background: linear-gradient(135deg, rgba(245, 158, 11, 0.14), rgba(22, 29, 36, 0.7));
  box-shadow: inset 3px 0 0 var(--amber), 0 4px 16px rgba(245, 158, 11, 0.08);
  transform: none;
}
.check__item input {
  width: 18px;
  height: 18px;
  margin-top: 2px;
  accent-color: var(--amber);
  cursor: pointer;
}
.check__item span {
  font-size: 14px;
  line-height: 1.45;
}

.result {
  margin-top: 28px;
  padding: 22px 18px;
  border: 1px solid var(--line);
  border-radius: 12px;
  background: rgba(22, 29, 36, 0.85);
  animation: rise 0.45s var(--ease) both;
}
.result.is-low {
  border-color: rgba(45, 212, 191, 0.45);
  box-shadow: inset 4px 0 0 var(--teal), 0 0 0 1px rgba(45, 212, 191, 0.08);
  background: linear-gradient(135deg, rgba(45, 212, 191, 0.08), rgba(22, 29, 36, 0.9));
}
.result.is-watch {
  border-color: rgba(245, 158, 11, 0.45);
  box-shadow: inset 4px 0 0 var(--amber), 0 0 0 1px rgba(245, 158, 11, 0.08);
  background: linear-gradient(135deg, rgba(245, 158, 11, 0.08), rgba(22, 29, 36, 0.9));
}
.result.is-high {
  border-color: rgba(239, 68, 68, 0.45);
  box-shadow: inset 4px 0 0 var(--signal), 0 0 0 1px rgba(239, 68, 68, 0.08);
  background: linear-gradient(135deg, rgba(239, 68, 68, 0.08), rgba(22, 29, 36, 0.9));
}
.result__band {
  font-family: var(--display);
  font-weight: 700;
  font-size: 22px;
  letter-spacing: -0.015em;
  margin-bottom: 8px;
}
.result.is-low .result__band { color: var(--teal); }
.result.is-watch .result__band { color: var(--amber); }
.result.is-high .result__band { color: var(--signal); }
.result__lead {
  color: var(--dim);
  font-size: 13px;
  margin-bottom: 16px;
}
.result__steps {
  display: grid;
  gap: 10px;
  counter-reset: step;
}
.result__steps li {
  position: relative;
  padding: 12px 12px 12px 44px;
  border-top: 1px solid rgba(232, 238, 242, 0.08);
  font-size: 13px;
  color: var(--paper);
}
.result__steps li::before {
  counter-increment: step;
  content: counter(step, decimal-leading-zero);
  position: absolute;
  left: 0;
  top: 12px;
  color: var(--dim);
  font-size: 12px;
  letter-spacing: 0.06em;
  font-family: var(--mono);
}

/* Address */
.address__form {
  display: grid;
  gap: 14px;
}
.address__label {
  display: grid;
  gap: 8px;
  font-size: 12px;
  letter-spacing: 0.08em;
  color: var(--dim);
}
.address__label input {
  width: 100%;
  padding: 14px 12px;
  border: 1px solid var(--line);
  border-radius: 8px;
  background: rgba(22, 29, 36, 0.8);
  font-size: 16px;
  letter-spacing: 0.02em;
  transition: border-color 0.2s ease, box-shadow 0.2s ease;
}
.address__label input:focus {
  outline: none;
  border-color: var(--teal);
  box-shadow: 0 0 0 3px rgba(45, 212, 191, 0.18);
}
.address__msg {
  margin-top: 14px;
  padding: 12px 14px;
  font-size: 13px;
  border: 1px solid var(--line);
  border-radius: 8px;
}
.address__msg.is-ok {
  color: var(--teal);
  background: var(--teal-dim);
  border-color: rgba(45, 212, 191, 0.35);
}
.address__msg.is-bad {
  color: var(--amber);
  background: var(--amber-dim);
  border-color: rgba(245, 158, 11, 0.35);
}
.address__msg.is-note {
  color: var(--dim);
  background: rgba(22, 29, 36, 0.8);
}

.disclaimer p {
  color: var(--dim);
  font-size: 13px;
  max-width: 58ch;
  margin-top: 12px;
}

.foot {
  display: flex;
  flex-wrap: wrap;
  justify-content: space-between;
  gap: 10px;
  padding: 28px 16px calc(28px + env(safe-area-inset-bottom, 0px));
  color: var(--dim);
  font-size: 11px;
  letter-spacing: 0.04em;
  background:
    radial-gradient(ellipse 40% 80% at 50% 100%, rgba(45, 212, 191, 0.06), transparent 60%);
}
.foot span:first-child {
  font-family: var(--display);
  font-weight: 700;
  color: var(--paper);
  letter-spacing: 0;
  text-transform: uppercase;
}

@media (prefers-reduced-motion: reduce) {
  .hero__img,
  .hero__copy,
  .hero .btn,
  .hero__brand::after,
  .trust__list,
  .result,
  .splash__brand {
    animation: none !important;
  }
  .btn:hover,
  .check__item:hover {
    transform: none;
  }
}

@media (min-width: 1101px) and (hover: hover) and (pointer: fine) {
  .top__burger { display: none; }
  .drawer {
    display: flex !important;
    flex-direction: row;
    justify-content: flex-end;
    gap: 4px;
    padding: 0 16px;
    background: transparent;
    border: 0;
    position: sticky;
    top: 54px;
    z-index: 70;
    pointer-events: none;
    backdrop-filter: none;
  }
  .drawer[hidden] { display: flex !important; }
  .drawer a {
    pointer-events: auto;
    border: 0;
    padding: 8px 12px;
    font-size: 12px;
    color: var(--dim);
    border-radius: 6px;
  }
  .drawer a:hover {
    color: var(--teal);
    background: rgba(45, 212, 191, 0.08);
  }
  .top__lang-menu { right: 0; }
  .hero__copy { padding: 64px 40px 56px; }
  .trust, .check, .address, .disclaimer { padding: 64px 24px; }
}

@media (max-width: 1100px), (hover: none) and (pointer: coarse) {
  .drawer {
    display: none;
    flex-direction: column;
    position: static;
    pointer-events: auto;
    background: rgba(18, 24, 32, 0.98);
    border-bottom: 1px solid var(--line);
  }
  .drawer:not([hidden]) { display: flex; }
  .drawer a {
    padding: 14px 16px;
    border-top: 1px solid var(--line);
    color: var(--paper);
  }
  .check__item span { font-size: 15px; line-height: 1.45; }
  .address__label input,
  .check__item input,
  .check__form .btn,
  .address__form .btn,
  .hero .btn { font-size: 16px; }
  .hero__brand { font-size: clamp(40px, 12vw, 64px); }
  .hero h1 { max-width: none; font-size: clamp(20px, 5vw, 26px); }
  .hero__lead { max-width: none; font-size: 15px; }
  .hero__copy { padding: 40px 16px 32px; }
  .hero .btn,
  .check__form .btn { width: 100%; text-align: center; }
}

/* Simplified Chinese */
html[lang^="zh"] {
  --display: "Noto Sans SC", "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", "Figtree", sans-serif;
}
html[lang^="zh"] body {
  font-family: var(--display);
  line-height: 1.7;
  letter-spacing: 0;
}
html[lang^="zh"] .splash__brand,
html[lang^="zh"] .top__brand,
html[lang^="zh"] .hero__brand,
html[lang^="zh"] .result__band,
html[lang^="zh"] h1,
html[lang^="zh"] h2 {
  font-family: var(--display);
  letter-spacing: 0;
  font-weight: 600;
  text-transform: none;
}
html[lang^="zh"] .hero h1 {
  max-width: 16em;
  line-height: 1.4;
}
html[lang^="zh"] .hero__lead,
html[lang^="zh"] .lead,
html[lang^="zh"] .check__lead,
html[lang^="zh"] .result__lead,
html[lang^="zh"] .disclaimer p {
  max-width: 36em;
  line-height: 1.75;
}
html[lang^="zh"] .section__k,
html[lang^="zh"] .splash__line,
html[lang^="zh"] .trust__list li,
html[lang^="zh"] .check__item span,
html[lang^="zh"] .drawer a,
html[lang^="zh"] .btn,
html[lang^="zh"] .top__lang,
html[lang^="zh"] .address__label,
html[lang^="zh"] .foot span:first-child {
  font-family: var(--display);
  letter-spacing: 0.06em;
  text-transform: none;
}
html[lang^="zh"] .section__k {
  letter-spacing: 0.14em;
  font-size: 12px;
}
html[lang^="zh"] .section__lead {
  max-width: 36em;
  line-height: 1.75;
  letter-spacing: 0;
}

@media (max-width: 1100px), (hover: none) and (pointer: coarse) {
  html[lang^="zh"] .hero__brand {
    font-size: clamp(34px, 11vw, 52px);
  }
  html[lang^="zh"] .hero h1 {
    font-size: clamp(18px, 4.8vw, 24px);
    max-width: none;
  }
  html[lang^="zh"] .check__item span {
    font-size: 15px;
    line-height: 1.5;
  }
  html[lang^="zh"] .result__band {
    font-size: 20px;
  }
}