:root {
  --black: #050706;
  --ink: #eff1ed;
  --muted: rgba(239, 241, 237, 0.62);
  --line: rgba(224, 231, 223, 0.3);
  --red: #e63c27;
  --red-deep: #bf2e20;
  --green: #5b8063;
  --serif: "Songti SC", "STSong", "Noto Serif CJK SC", "Source Han Serif SC", serif;
  --sans: "PingFang SC", "Noto Sans CJK SC", "Microsoft YaHei", system-ui, sans-serif;
}

* {
  box-sizing: border-box;
}

html,
body {
  min-height: 100%;
  margin: 0;
  background: var(--black);
}

body {
  color: var(--ink);
  font-family: var(--sans);
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
}

button {
  font: inherit;
}

.app-shell {
  min-height: 100svh;
  width: 100%;
  max-width: 430px;
  margin: 0 auto;
  overflow: hidden;
  background: var(--black) url("./assets/jinggangshan-mountains-86c0dc6a.webp") center/cover no-repeat;
}

.screen {
  position: relative;
  display: flex;
  flex-direction: column;
  min-height: 100svh;
  padding: max(20px, env(safe-area-inset-top)) 24px max(26px, env(safe-area-inset-bottom));
}

.brand-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  min-height: 32px;
}

.brand-lockup {
  display: flex;
  align-items: center;
  gap: 8px;
  font-size: 12px;
  font-weight: 600;
  letter-spacing: 0.08em;
  white-space: nowrap;
}

.brand-symbol {
  display: grid;
  width: 25px;
  height: 25px;
  place-items: center;
  border: 1px solid rgba(255, 255, 255, 0.84);
  border-radius: 50%;
  color: #fff;
  font-family: var(--serif);
  font-size: 13px;
  font-weight: 700;
  letter-spacing: 0;
}

.brand-header--compact .brand-lockup {
  opacity: 0.88;
}

.text-button {
  padding: 6px 0;
  border: 0;
  background: transparent;
  color: rgba(239, 241, 237, 0.55);
  font-size: 12px;
  cursor: pointer;
}

.screen--intro .brand-header {
  margin-top: 4px;
}

.intro-copy {
  margin-top: clamp(68px, 15vh, 124px);
}

.intro-copy h1,
.question-region h1,
.result-content h1 {
  margin: 0;
  color: #fff;
  font-family: var(--serif);
  font-weight: 600;
  letter-spacing: -0.045em;
}

.intro-copy h1 {
  max-width: 340px;
  font-size: clamp(46px, 13.2vw, 58px);
  line-height: 1.06;
}

.intro-copy h1 span {
  color: var(--red);
}

.intro-copy p {
  margin: 26px 0 0;
  color: rgba(255, 255, 255, 0.77);
  font-size: 15px;
  letter-spacing: 0.08em;
}

.intro-spacer {
  flex: 1;
  min-height: 170px;
}

.bottom-stack {
  display: grid;
  gap: 22px;
}

.primary-button {
  width: 100%;
  min-height: 56px;
  border: 0;
  border-radius: 4px;
  background: linear-gradient(100deg, var(--red-deep), var(--red));
  color: #fff;
  font-family: var(--sans);
  font-size: 18px;
  font-weight: 700;
  letter-spacing: 0.08em;
  cursor: pointer;
  transition: transform 150ms ease, filter 150ms ease, opacity 150ms ease;
}

.primary-button:hover,
.primary-button:focus-visible {
  filter: brightness(1.08);
}

.primary-button:active {
  transform: translateY(1px);
}

.primary-button:disabled {
  cursor: not-allowed;
  opacity: 0.34;
}

.activity-notice {
  margin: 0;
  color: rgba(239, 241, 237, 0.45);
  font-size: 12px;
  letter-spacing: 0.08em;
  text-align: center;
}

.activity-notice::before,
.activity-notice::after {
  display: inline-block;
  width: 21px;
  height: 1px;
  margin: 0 10px 3px;
  background: rgba(239, 241, 237, 0.3);
  content: "";
}

.screen--quiz {
  padding-top: max(20px, env(safe-area-inset-top));
}

.progress-region {
  margin-top: 46px;
}

.progress-track {
  height: 3px;
  overflow: hidden;
  background: rgba(255, 255, 255, 0.2);
}

.progress-track span {
  display: block;
  height: 100%;
  background: var(--red);
  transition: width 240ms ease;
}

.progress-region p {
  margin: 14px 0 0;
  color: rgba(255, 255, 255, 0.7);
  font-family: var(--serif);
  font-size: 15px;
  letter-spacing: 0.06em;
  text-align: center;
}

.progress-region strong {
  color: var(--red);
  font-size: 21px;
  font-weight: 500;
}

.question-region {
  display: flex;
  flex: 1;
  flex-direction: column;
  padding-top: clamp(40px, 7vh, 70px);
}

.question-region h1 {
  max-width: 340px;
  font-size: clamp(35px, 10.4vw, 46px);
  line-height: 1.22;
}

.options {
  display: grid;
  gap: 12px;
  margin-top: clamp(42px, 8vh, 76px);
}

.option-row {
  display: flex;
  align-items: center;
  min-height: 67px;
  gap: 15px;
  padding: 14px 16px;
  border: 1px solid var(--line);
  border-radius: 4px;
  background: rgba(4, 7, 5, 0.22);
  color: rgba(255, 255, 255, 0.9);
  font-family: var(--serif);
  font-size: 17px;
  line-height: 1.35;
  text-align: left;
  cursor: pointer;
  transition: border-color 160ms ease, background-color 160ms ease;
}

.option-row:hover,
.option-row:focus-visible {
  border-color: rgba(238, 62, 42, 0.8);
}

.option-row--selected {
  border-color: var(--red);
  background: rgba(9, 11, 9, 0.44);
}

.option-marker {
  display: grid;
  width: 25px;
  height: 25px;
  flex: 0 0 25px;
  place-items: center;
  border: 1px solid rgba(255, 255, 255, 0.48);
  border-radius: 50%;
  color: #050706;
  font-family: var(--sans);
  font-size: 16px;
  font-weight: 800;
}

.option-row--selected .option-marker {
  border-color: var(--red);
  background: var(--red);
}

.bottom-stack--quiz {
  margin-top: 20px;
}

.screen--result {
  align-items: stretch;
}

.result-content {
  display: flex;
  flex: 1;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  padding: 45px 0 30px;
  text-align: center;
}

.result-check {
  display: grid;
  width: 88px;
  height: 88px;
  margin-bottom: 35px;
  place-items: center;
  border-radius: 50%;
  background: var(--red);
  color: var(--black);
  font-size: 53px;
  font-weight: 900;
  line-height: 1;
}

.result-content h1 {
  font-size: clamp(56px, 16vw, 68px);
  line-height: 1;
}

.result-copy {
  margin: 28px 0 0;
  color: rgba(255, 255, 255, 0.86);
  font-family: var(--serif);
  font-size: 19px;
  line-height: 1.75;
}

.result-divider {
  display: flex;
  align-items: center;
  width: 100%;
  gap: 11px;
  margin: 33px 0 34px;
}

.result-divider span {
  height: 1px;
  flex: 1;
  background: rgba(89, 130, 97, 0.75);
}

.result-divider i {
  width: 8px;
  height: 8px;
  transform: rotate(45deg);
  background: var(--red);
}

.redeem-panel {
  display: grid;
  width: 100%;
  min-height: 160px;
  padding: 26px 18px;
  place-content: center;
  border: 1px solid rgba(89, 130, 97, 0.95);
  border-radius: 5px;
  background: rgba(1, 12, 6, 0.35);
}

.redeem-panel span {
  color: #fff;
  font-family: var(--serif);
  font-size: clamp(46px, 13vw, 57px);
  letter-spacing: -0.05em;
  line-height: 1;
}

.redeem-panel small {
  margin-top: 18px;
  color: rgba(255, 255, 255, 0.52);
  font-size: 12px;
  letter-spacing: 0.12em;
}

@media (min-width: 560px) {
  .app-shell {
    min-height: 100vh;
    box-shadow: 0 0 0 1px rgba(255, 255, 255, 0.04), 0 30px 100px rgba(0, 0, 0, 0.55);
  }
}

@media (max-height: 720px) {
  .intro-copy {
    margin-top: 48px;
  }

  .intro-spacer {
    min-height: 96px;
  }

  .question-region {
    padding-top: 30px;
  }

  .options {
    margin-top: 28px;
  }

  .option-row {
    min-height: 57px;
    font-size: 15px;
  }

  .result-content {
    padding-top: 26px;
  }

  .result-check {
    width: 66px;
    height: 66px;
    margin-bottom: 22px;
    font-size: 42px;
  }

  .result-copy {
    margin-top: 17px;
    font-size: 17px;
  }

  .result-divider {
    margin: 22px 0;
  }

  .redeem-panel {
    min-height: 125px;
  }
}