:root { color-scheme: light; --ink: #1d1d1f; --secondary: #6e6e73; --blue: #0071e3; --green: #24834b; }
* { box-sizing: border-box; -webkit-tap-highlight-color: transparent; }
body { margin: 0; background: #f5f5f7; color: var(--ink); font-family: -apple-system, BlinkMacSystemFont, "PingFang SC", "Microsoft YaHei", sans-serif; letter-spacing: 0; }
button, a { touch-action: manipulation; }
button { font: inherit; cursor: pointer; }
button:disabled { cursor: default; }
button:focus-visible, a:focus-visible { outline: 3px solid #0071e3; outline-offset: 5px; }
[hidden] { display: none !important; }
.shell { max-width: 820px; margin: auto; padding: 0 32px; }
header { min-height: 86px; display: flex; align-items: center; gap: 16px; border-bottom: 1px solid #dedee3; }
.brand { flex: 1; font-size: 21px; font-weight: 700; }.brand span { margin-left: 12px; color: var(--secondary); font-size: 13px; font-weight: 400; }
.icon-button { border: 0; background: transparent; color: var(--blue); width: 44px; height: 44px; display: inline-grid; place-items: center; text-decoration: none; font-size: 30px; border-radius: 8px; flex-shrink: 0; }
.icon-button:hover { background: #e8e8ed; }
.journey { margin-top: 26px; display: flex; justify-content: space-between; font-size: 14px; color: var(--secondary); }
#collection { color: #936511; font-weight: 650; }
.progress { height: 5px; background: #e2e3e7; margin-top: 12px; border-radius: 4px; overflow: hidden; }.progress i { display: block; width: 0; height: 100%; background: var(--green); transition: width .35s ease; }
.experience { text-align: center; padding: 24px 0 26px; min-height: 610px; }
.intro p { color: var(--secondary); font-size: 16px; line-height: 1.6; margin: 8px 0; }.intro #eyebrow { font-size: 12px; color: var(--green); font-weight: 650; }
h1 { font-size: 30px; line-height: 1.3; margin: 12px 0; font-weight: 700; }
.learn { margin: 12px auto 0; }
.word-button { border: 0; background: transparent; color: var(--ink); display: block; width: 220px; height: 192px; margin: auto; padding: 0; font-size: 152px; font-weight: 500; line-height: 1.15; }
.meaning { min-height: 86px; }.meaning > span { font-size: 30px; vertical-align: middle; margin-right: 10px; }.meaning strong { font-size: 24px; vertical-align: middle; }.meaning p { font-size: 16px; margin: 10px 0; color: var(--secondary); }
.feedback { min-height: 28px; font-size: 17px; font-weight: 600; line-height: 1.6; margin: 20px 0 16px; color: var(--green); }
.primary { display: inline-flex; align-items: center; justify-content: center; gap: 24px; min-width: 228px; max-width: 100%; min-height: 54px; border: 0; border-radius: 8px; padding: 14px 24px; background: var(--blue); color: #fff; font-size: 19px; font-weight: 600; }.primary:hover { background: #0063c7; }.primary:active { transform: scale(.98); }
.listen { margin: 20px 0 24px; border: 0; background: #e7eef9; color: #0062c5; border-radius: 8px; min-height: 48px; padding: 10px 22px; font-size: 18px; }.listen span { margin-right: 6px; font-size: 24px; }
.choices { display: grid; grid-template-columns: repeat(3, minmax(0, 1fr)); gap: 18px; max-width: 660px; margin: auto; }
.choice { aspect-ratio: 1; border: 2px solid transparent; border-radius: 8px; background: #fff; color: var(--ink); font-size: 104px; font-weight: 500; box-shadow: 0 4px 18px #00000006; padding: 0; line-height: 1.2; transition: background .2s, transform .2s; }
.choice:hover:not(:disabled) { background: #ecf3fd; }.choice:active:not(:disabled) { transform: scale(.96); }.choice.correct { color: #176c39; background: #e5f4e9; border-color: #48a56b; animation: delight .5s ease; }.choice.hint { border-color: #0071e3; }.choice.tried { color: #86868b; background: #ececf0; }
.reward { height: 48px; margin: 16px 0 0; font-size: 36px; }.audio-note { font-size: 16px; color: var(--secondary); line-height: 1.5; }
.finish { padding: 20px 0; }.big-star { font-size: 112px; animation: delight .6s ease; }.finish p { color: var(--secondary); line-height: 1.8; }#finish-words { font-size: 40px; color: var(--ink); word-spacing: 20px; }
footer { display: flex; align-items: center; justify-content: space-between; min-height: 65px; border-top: 1px solid #dedee3; padding-bottom: env(safe-area-inset-bottom); color: var(--secondary); font-size: 12px; }.text-button { color: var(--secondary); border: 0; background: none; min-height: 44px; padding: 8px; }
dialog { max-width: 480px; width: calc(100% - 32px); border: 0; border-radius: 8px; padding: 24px; box-shadow: 0 16px 70px #0003; }dialog::backdrop { background: #0005; }.dialog-heading { display: flex; justify-content: space-between; align-items: center; }h2 { font-size: 23px; margin: 0; }dialog p { color: var(--secondary); line-height: 1.7; font-size: 14px; }.word-list { font-size: 28px; line-height: 1.8; word-spacing: 14px; }.reset { background: #fff; color: #c93535; border: 1px solid #ddd; min-height: 44px; border-radius: 8px; padding: 8px 16px; }
@keyframes delight { 0%,100% { transform: scale(1); } 45% { transform: scale(1.07) rotate(-3deg); } }
@media(max-width: 600px) { .shell { padding: 0 20px; }header { min-height: 72px; gap: 8px; }.brand { font-size: 19px; }.brand span { display: none; }.experience { min-height: 570px; padding-top: 20px; }h1 { font-size: 26px; }.choices { gap: 10px; }.choice { font-size: 72px; }.word-button { font-size: 144px; height: 180px; }.intro p { font-size: 15px; }.journey { margin-top: 20px; }#quiz { padding-top: 12px; }.reward { margin-top: 24px; }.feedback { font-size: 16px; }.listen { margin-bottom: 32px; } }
@media(max-width: 360px) { .shell { padding: 0 14px; }.choice { font-size: 62px; }.choices { gap: 8px; }h1 { font-size: 24px; } }
@media(prefers-reduced-motion: reduce) { *, *::before, *::after { animation: none !important; transition: none !important; } }