@layer properties{@supports (((-webkit-hyphens:none)) and (not (margin-trim:inline))) or ((-moz-orient:inline) and (not (color:rgb(from red r g b)))){*,:before,:after,::backdrop{--tw-blur:initial;--tw-brightness:initial;--tw-contrast:initial;--tw-grayscale:initial;--tw-hue-rotate:initial;--tw-invert:initial;--tw-opacity:initial;--tw-saturate:initial;--tw-sepia:initial;--tw-drop-shadow:initial;--tw-drop-shadow-color:initial;--tw-drop-shadow-alpha:100%;--tw-drop-shadow-size:initial}}}@layer theme{:root,:host{--font-sans:ui-sans-serif, system-ui, sans-serif, "Apple Color Emoji", "Segoe UI Emoji", "Segoe UI Symbol", "Noto Color Emoji";--font-mono:ui-monospace, SFMono-Regular, Menlo, Monaco, Consolas, "Liberation Mono", "Courier New", monospace;--spacing:.25rem;--default-font-family:var(--font-sans);--default-mono-font-family:var(--font-mono)}}@layer base{*,:after,:before,::backdrop{box-sizing:border-box;border:0 solid;margin:0;padding:0}::file-selector-button{box-sizing:border-box;border:0 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components;@layer utilities{.visible{visibility:visible}.fixed{position:fixed}.start{inset-inline-start:var(--spacing)}.end{inset-inline-end:var(--spacing)}.isolate{isolation:isolate}.hidden{display:none}.inline{display:inline}.table{display:table}.filter{filter:var(--tw-blur,) var(--tw-brightness,) var(--tw-contrast,) var(--tw-grayscale,) var(--tw-hue-rotate,) var(--tw-invert,) var(--tw-saturate,) var(--tw-sepia,) var(--tw-drop-shadow,)}}:root{--ink:#203129;--forest:#294a3a;--sage:#7b9582;--cream:#f4efe4;--paper:#fffdf8;--terracotta:#c76942;--line:#20312929}*{box-sizing:border-box}html{background:var(--cream);min-width:320px}body{color:var(--ink);background:linear-gradient(#20312908 1px, transparent 1px), linear-gradient(90deg, #20312908 1px, transparent 1px), var(--cream);background-size:32px 32px;margin:0;font-family:Inter,ui-sans-serif,-apple-system,BlinkMacSystemFont,Segoe UI,PingFang SC,Hiragino Sans GB,Microsoft 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var(--line);color:var(--sage);letter-spacing:.08em;border-radius:999px;padding:5px 10px;font-size:11px;font-style:normal;font-weight:700}.phonetic{color:var(--sage);margin-top:10px;font-family:Georgia,Times New Roman,serif;font-size:18px}.divider{background:var(--line);width:100%;height:1px;margin:25px 0 22px}.meaning{font-family:Songti SC,SimSun,serif;font-size:clamp(23px,2.7vw,32px);font-weight:600}.usage-note{color:var(--sage);margin-top:10px;font-size:11px;line-height:1.6}.example-block{gap:7px;margin-top:auto;display:grid}.example-block small{color:var(--terracotta);letter-spacing:.18em;margin-bottom:3px;font-size:9px;font-weight:750}.example-block span[lang=en]{font-family:Georgia,Times New Roman,serif;font-size:clamp(17px,2vw,21px);line-height:1.4}.example-block span[lang=zh-CN]{color:#6c7972;font-size:13px}.back-hint{color:#9aa59f;margin:0;position:absolute;bottom:24px;right:28px}.audio-controls{justify-content:center;gap:10px;margin-top:18px;display:flex}.audio-controls 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button:last-child{justify-self:end}.controls button:hover,.controls button:focus-visible{border-color:var(--forest);color:var(--paper);background:var(--forest);outline:none}.controls .shuffle-button{color:var(--paper);background:var(--terracotta);border-color:var(--terracotta)}.controls .shuffle-button:hover,.controls .shuffle-button:focus-visible{background:#a84f2d;border-color:#a84f2d}.controls svg{width:16px;height:16px}.counter{justify-content:center;align-items:baseline;gap:5px;margin-top:17px;font-family:Georgia,Times New Roman,serif;display:flex}.counter strong{color:var(--terracotta);font-size:20px;font-weight:400}.counter span{color:#8c9891;font-size:12px}footer{border-top:1px solid var(--line);color:#8c9891;letter-spacing:.1em;justify-content:space-between;align-items:center;min-height:62px;font-size:10px;display:flex}@media (max-width:900px){.page-shell{width:min(680px,100% - 40px)}.site-header{height:86px}.learning-layout{grid-template-columns:1fr;gap:38px;padding:44px 0 34px}.intro{text-align:center}.intro-copy,.word-map{margin-left:auto;margin-right:auto}.study-area{justify-self:center}}@media (max-width:560px){.page-shell{width:min(100% - 24px,470px)}.site-header{height:74px}.brand-mark{width:36px;height:36px;font-size:11px}.brand strong{font-size:18px}.category-navigation{max-width:calc(100% - 96px)}.category-switcher{gap:2px;padding:2px}.category-switcher button{gap:5px;min-height:32px;padding:6px 9px;font-size:10px}.category-switcher small{display:none}.learning-layout{gap:30px;padding:36px 0 28px}.eyebrow{margin-bottom:15px}.intro h1{font-size:clamp(38px,12vw,52px)}.intro-copy{margin:22px auto 25px;font-size:14px;line-height:1.75}.word-map{grid-template-columns:repeat(4,1fr);gap:3px 8px}.word-map button{justify-content:center;gap:4px;padding:5px 0;font-size:11px}.word-map button span{display:none}.flashcard{aspect-ratio:.82}.card-front{grid-template-rows:62% 38%;grid-template-columns:1fr}.action-image{min-height:0}.front-content{padding:20px}.front-content:before{top:18px;right:20px}.card-number{margin-bottom:10px}.front-content strong{font-size:clamp(38px,12vw,54px)}.front-content strong.is-long{font-size:clamp(30px,9vw,42px)}.flip-hint{margin-top:15px}.card-back{padding:30px 26px}.word-heading{margin-top:12px}.word-heading strong{font-size:clamp(39px,12vw,54px)}.word-heading strong.is-long{font-size:clamp(30px,9vw,42px)}.divider{margin:20px 0 18px}.meaning{font-size:25px}.example-block{margin-bottom:35px}.back-hint{bottom:17px;right:22px}.controls{gap:7px;margin-top:16px}.audio-controls{margin-top:15px}.audio-controls button{min-height:36px;padding:7px 13px;font-size:10px}.controls button{min-height:40px;padding:8px 11px;font-size:11px}.controls .shuffle-button{width:42px;padding:0;font-size:0}.controls .shuffle-button svg{width:17px;height:17px}footer{justify-content:center;min-height:54px}.keyboard-note{display:none}}@media (max-width:390px){.brand small{display:none}.brand{gap:8px}.category-switcher button{padding-left:5px;padding-right:5px;font-size:9px}}@media (prefers-reduced-motion:reduce){.category-navigation:before,.category-navigation:after,.flashcard,.word-map button,.progress-line span{transition:none}.category-switcher{scroll-behavior:auto}}@property --tw-blur{syntax:"*";inherits:false}@property --tw-brightness{syntax:"*";inherits:false}@property --tw-contrast{syntax:"*";inherits:false}@property --tw-grayscale{syntax:"*";inherits:false}@property --tw-hue-rotate{syntax:"*";inherits:false}@property --tw-invert{syntax:"*";inherits:false}@property --tw-opacity{syntax:"*";inherits:false}@property --tw-saturate{syntax:"*";inherits:false}@property --tw-sepia{syntax:"*";inherits:false}@property --tw-drop-shadow{syntax:"*";inherits:false}@property --tw-drop-shadow-color{syntax:"*";inherits:false}@property --tw-drop-shadow-alpha{syntax:"<percentage>";inherits:false;initial-value:100%}@property --tw-drop-shadow-size{syntax:"*";inherits:false}