*,:after,:before{box-sizing:border-box}html{text-size-adjust:100%;scroll-behavior:smooth;scroll-padding-top:60px}body{margin:0;padding:0;min-height:100vh;line-height:1.6;color:#1a1a1a;background:#fff}:root{--color-text:#1a1a1a;--color-text-secondary:#666;--color-text-translation:#4a5568;--color-background:#fff;--color-background-hover:#f5f5f5;--color-background-section:#fafafa;--color-border:#e2e8f0;--color-accent:#dc2626;--color-accent-light:#ebf8ff;--font-main:inherit;--font-cjk:"PingFang SC","Hiragino Sans GB","Microsoft YaHei","Noto Sans SC",sans-serif;--font-size-base:18px;--font-size-small:14px;--font-size-large:22px;--line-height:1.8;--spacing-xs:4px;--spacing-sm:8px;--spacing-md:16px;--spacing-lg:24px;--spacing-xl:32px;--header-height:60px;--bottom-nav-height:56px;--shadow-popup:0 4px 12px rgba(0,0,0,.15);--hero-padding-bottom:700px;--hero-card-margin-bottom:-820px;--hero-card-translateY:260px}.page{--font-scale:1;position:relative;width:100%;max-width:900px;margin:0 auto;padding:var(--spacing-lg) var(--spacing-xl);padding-top:calc(var(--header-height) + 1em + var(--spacing-lg) + env(safe-area-inset-top, 0px));padding-bottom:calc(var(--bottom-nav-height) + 1em + var(--spacing-lg) + env(safe-area-inset-bottom, 0px));font-family:inherit;font-size:calc(var(--font-size-base) * var(--font-scale));line-height:var(--line-height);color:var(--color-text)}.reader__controls{display:flex;align-items:center;gap:var(--spacing-sm)}.page__toggle-btn{display:flex;align-items:center;justify-content:center;padding:8px 12px;min-height:44px;background:#f5f5f5;border:1px solid var(--color-border);border-radius:4px;font-size:14px;font-weight:500;color:var(--color-text-secondary);cursor:pointer;transition:all .15s ease}.page__toggle-btn:hover{background:#e5e5e5}.page__toggle-btn--active{background:var(--color-accent);border-color:var(--color-accent);color:#fff}.page__toggle-btn--active:hover{background:#2563eb}.page__lang-btn{display:flex;align-items:center;justify-content:center;padding:4px 10px;min-height:32px;border:1px solid #dc2626;border-radius:4px;font-size:14px;font-weight:600;color:#fff;cursor:pointer;transition:all .15s ease}.page__lang-btn,.page__lang-btn:hover{background:#dc2626}.page__font-controls{display:flex;gap:2px;background:#f5f5f5;border:1px solid var(--color-border);border-radius:4px;overflow:hidden}.page__font-btn{display:flex;align-items:center;justify-content:center;padding:4px 8px;min-height:32px;background:transparent;border:none;font-size:14px;font-weight:600;color:var(--color-text-secondary);cursor:pointer;transition:all .15s ease}.page__font-btn:hover:not(:disabled){background:#e5e5e5;color:var(--color-text)}.page__font-btn:disabled{opacity:.4;cursor:not-allowed}.page__font-btn:focus{outline:none}.page__number-badge{width:36px;height:36px;display:flex;align-items:center;justify-content:center;background:#1a1a1a;color:#fff;font-size:14px;font-weight:600;border-radius:50%;box-shadow:0 2px 4px rgba(0,0,0,.2)}@media (min-width:1200px){.page{max-width:1000px}}@media (min-width:1600px){.page{max-width:1100px}}.page__header{margin-bottom:var(--spacing-xl);padding-bottom:var(--spacing-md);border-bottom:2px solid var(--color-border)}.page__number{display:block;font-size:var(--font-size-small);color:var(--color-text-secondary);margin-bottom:var(--spacing-xs)}.page__title{margin:0;font-size:var(--font-size-large);font-weight:600;font-family:var(--font-cjk)}.page__content{display:flex;flex-direction:column;gap:var(--spacing-xl)}.lesson-header{display:flex;align-items:stretch;margin-bottom:var(--spacing-xl);border-radius:6px;overflow:hidden;box-shadow:0 2px 8px rgba(0,0,0,.1)}.lesson-header__badge{display:flex;flex-direction:column;align-items:center;justify-content:center;padding:var(--spacing-lg) var(--spacing-xl);background:#fff;min-width:120px}.lesson-header__number{font-size:48px;font-weight:700;color:#dc2626;line-height:1}.lesson-header__label{font-size:18px;font-weight:600;color:#dc2626;text-transform:uppercase;margin-top:var(--spacing-xs)}.lesson-header__banner{flex:1 1;display:flex;align-items:center;background:linear-gradient(135deg,#dc2626,#b91c1c);padding:var(--spacing-lg) var(--spacing-xl)}.lesson-header__content{color:#fff}.lesson-header__pinyin{margin:0 0 var(--spacing-xs) 0;font-size:16px;font-weight:400;opacity:.9;letter-spacing:2px}.lesson-header__title{margin:0 0 var(--spacing-sm) 0;font-size:36px;font-weight:700;font-family:var(--font-cjk);text-shadow:0 2px 4px rgba(0,0,0,.2)}.lesson-header__translation{margin:0;font-size:18px;font-weight:500;opacity:.95}@media (max-width:768px){.lesson-header{flex-direction:column}.lesson-header__badge{flex-direction:row;justify-content:flex-start;gap:var(--spacing-md);padding:var(--spacing-md) var(--spacing-lg);min-width:unset}.lesson-header__label{margin-bottom:0}.lesson-header__number{font-size:48px}.lesson-header__banner{padding:var(--spacing-md) var(--spacing-lg)}.lesson-header__title{font-size:28px}.lesson-header__pinyin{font-size:14px}.lesson-header__translation{font-size:16px}}@media (max-width:480px){.lesson-header__badge{padding:var(--spacing-sm) var(--spacing-md)}.lesson-header__number{font-size:36px}.lesson-header__banner{padding:var(--spacing-sm) var(--spacing-md)}.lesson-header__title{font-size:24px}.lesson-header__pinyin{font-size:12px}.lesson-header__translation{font-size:14px}}.section{padding:0;background:transparent}.section__sentences{display:flex;flex-direction:column;gap:var(--spacing-md);padding:var(--spacing-md);background:var(--color-background-section);border-radius:0 6px 6px 6px}.section--dialogue .section__sentences{background:#fff;border-radius:10px;box-shadow:0 2px 8px rgba(0,0,0,.1),0 6px 24px rgba(0,0,0,.06);padding:var(--spacing-sm) var(--spacing-md)}.section--vocabulary .section__header{display:none}.section--vocabulary .section__sentences{background:#fff;padding:var(--spacing-sm) var(--spacing-md);border-radius:10px;box-shadow:0 2px 8px rgba(0,0,0,.1),0 6px 24px rgba(0,0,0,.06)}.section--vocabulary .sentence{border-bottom:1px solid rgba(0,0,0,.06)}.section--vocabulary .sentence:last-child{border-bottom:none}.section--vocabulary .sentence__body{display:contents}.section--vocabulary .sentence__text-block{display:grid;grid-template-columns:40% 1fr;grid-gap:0 var(--spacing-xl);gap:0 var(--spacing-xl);padding:2px 0}.section--vocabulary .sentence__text-row{display:inline;grid-column:1;grid-row:1}.section--vocabulary .sentence__text{font-weight:400}.section--vocabulary .sentence__translation-inline{color:var(--color-text-translation);font-size:calc(var(--font-size-small) * var(--font-scale, 1));font-style:normal;grid-column:2;grid-row:1;align-self:start;margin-top:.35em}.section--grammar .section__sentences{background:#fff;gap:0;padding:0}.section--grammar .sentence{padding:var(--spacing-sm) var(--spacing-md)}.section--grammar .sentence:not([data-numbered=true]):not(:has(.sentence__checkbox)):not(.sentence--indented):not(.sentence--dialogue-grid):not(.sentence--table-only){background:#f0fff4}.section--grammar .sentence:has(.sentence__checkbox)~.sentence{background:transparent!important}.section--grammar .sentence--dialogue-grid{background:transparent!important}.section--grammar .sentence:has(.sentence__checkbox){margin-top:var(--spacing-md);padding-top:var(--spacing-md)}.section--exercise .sentence[data-numbered=true] .sentence__pinyin,.section--exercise .sentence[data-numbered=true] .sentence__translation-inline,.section--grammar .sentence[data-numbered=true] .sentence__pinyin,.section--grammar .sentence[data-numbered=true] .sentence__translation-inline{padding-left:1.8em}.grammar-table{border:2px solid var(--color-border);border-radius:6px;overflow-x:auto;margin:var(--spacing-md)}.grammar-table__row{display:grid}.grammar-table__row+.grammar-table__row{border-top:1px solid var(--color-border)}.grammar-table__row--header{background:#fff3e0;border-bottom:2px solid var(--color-border)}.grammar-table__cell{padding:var(--spacing-sm) var(--spacing-xs);font-size:calc(var(--font-size-base) * var(--font-scale, 1));text-align:center;white-space:pre-line}.grammar-table__cell+.grammar-table__cell{border-left:1px solid var(--color-border)}.grammar-table__cell--header{display:flex;flex-direction:column;align-items:center;justify-content:center;gap:4px;padding:var(--spacing-md) var(--spacing-sm);text-align:center;min-width:140px}.grammar-table__cell-label{font-weight:600;font-size:calc(var(--font-size-base) * var(--font-scale, 1))}.grammar-table__cell-sub{font-size:calc(var(--font-size-small) * var(--font-scale, 1));color:var(--color-text-secondary)}.sentence--indented{padding-left:calc(var(--spacing-md) + 3em)!important}.sentence--image-only{padding:var(--spacing-sm) 0;display:flex;justify-content:center}.sentence__inline-image{max-width:100%;height:auto;border-radius:4px}.sentence--table-only{padding:var(--spacing-sm) var(--spacing-md)}.sentence__table{width:100%;border-collapse:collapse;font-size:.95rem}.sentence__table td,.sentence__table th{border:1px solid 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ease}.matching__image-card:hover:not(:disabled){border-color:var(--color-accent);transform:translateY(-2px);box-shadow:0 4px 12px rgba(0,0,0,.1)}.matching__image-card--selected{border-color:var(--color-accent);box-shadow:0 0 0 3px rgba(49,130,206,.3)}.matching__image-card--matched{border-color:#16a34a;opacity:.7;cursor:default}.matching__image-card--matched:hover{transform:none;box-shadow:none}.matching__image{width:100%;height:100%;object-fit:cover}.matching__check{position:absolute;top:50%;left:50%;transform:translate(-50%,-50%);width:48px;height:48px;background:#16a34a;color:#fff;border-radius:50%;align-items:center;font-size:24px;font-weight:700;box-shadow:0 2px 8px rgba(0,0,0,.2)}.matching__check,.matching__words{display:flex;justify-content:center}.matching__words{flex-wrap:wrap;gap:var(--spacing-sm)}.matching__word-card{display:flex;flex-direction:column;align-items:center;padding:var(--spacing-sm) var(--spacing-md);background:#fff;border:2px solid 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#16a34a;border-radius:6px;margin-top:var(--spacing-md);animation:fadeIn .3s ease}.matching__complete-icon{font-size:24px}.matching__complete-text{font-size:calc(var(--font-size-base) * var(--font-scale, 1));font-weight:600;color:#16a34a}.fillblank{padding:var(--spacing-md)}.fillblank__progress{display:flex;align-items:center;gap:var(--spacing-sm);margin-bottom:var(--spacing-lg)}.fillblank__progress-text{font-size:calc(var(--font-size-small) * var(--font-scale, 1));font-weight:600;color:var(--color-accent);min-width:3em}.fillblank__progress-bar{flex:1 1;height:6px;background:var(--color-border);border-radius:3px;overflow:hidden}.fillblank__progress-fill{height:100%;background:var(--color-accent);border-radius:3px;transition:width .3s ease}.fillblank__options{display:flex;flex-wrap:wrap;gap:var(--spacing-md);justify-content:center;margin-bottom:var(--spacing-lg);padding:var(--spacing-md);background:#f8fafc;border-radius:6px;border:1px solid var(--color-border)}.fillblank__option{display:flex;align-items:center;gap:var(--spacing-sm);padding:var(--spacing-sm) var(--spacing-md);background:#fff;border:2px solid var(--color-border);border-radius:6px;cursor:pointer;transition:all .2s ease;opacity:.6}.fillblank__option--active{opacity:1;cursor:pointer}.fillblank__option--active:hover{border-color:var(--color-accent);background:var(--color-accent-light)}.fillblank__option:disabled{cursor:not-allowed}.fillblank__option-label{font-size:calc(var(--font-size-small) * var(--font-scale, 1));font-weight:700;color:#dc2626;min-width:1.5em}.fillblank__option-word{font-size:calc(var(--font-size-base) * var(--font-scale, 1));font-family:var(--font-cjk);font-weight:500;color:var(--color-text)}.fillblank__sentences{display:flex;flex-direction:column;gap:var(--spacing-md)}.fillblank__sentence{display:flex;gap:var(--spacing-sm);padding:var(--spacing-sm) 0;transition:background .2s ease}.fillblank__sentence--correct{background:#f0fdf4;border-radius:3px;padding:var(--spacing-sm);margin:0 calc(-1 * var(--spacing-sm))}.fillblank__sentence--wrong{animation:shake .5s ease}.fillblank__sentence-number{color:var(--color-text-secondary);min-width:2.5em;flex-shrink:0}.fillblank__sentence-content,.fillblank__sentence-number{font-size:calc(var(--font-size-base) * var(--font-scale, 1))}.fillblank__sentence-content{font-family:var(--font-cjk);line-height:2;color:var(--color-text)}.fillblank__speaker{font-weight:600;color:var(--color-accent);margin-right:var(--spacing-xs)}.fillblank__blank{display:inline-flex;align-items:center;justify-content:center;min-width:4em;padding:2px var(--spacing-sm);margin:0 2px;background:#f1f5f9;border:2px dashed var(--color-border);border-radius:3px;cursor:pointer;font-family:var(--font-cjk);font-size:calc(var(--font-size-base) * var(--font-scale, 1));color:var(--color-text-secondary);transition:all .2s 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1));font-family:var(--font-cjk);line-height:2}.mc__number{color:var(--color-text-secondary);flex-shrink:0}.mc__text{color:var(--color-text)}.mc__blank{display:inline-block;min-width:4em;padding:2px var(--spacing-sm);margin:0 2px;background:#f1f5f9;border:2px dashed var(--color-border);border-radius:3px;text-align:center;font-family:var(--font-cjk);color:var(--color-text-secondary);vertical-align:middle}.mc__blank--correct{border-color:#16a34a;border-style:solid;background:#dcfce7;color:#16a34a}.mc__blank--wrong{border-color:#dc2626;border-style:solid;background:#fef2f2;color:#dc2626}.mc__options{display:flex;flex-wrap:wrap;gap:var(--spacing-md);padding-left:2.5em}.mc__option{display:flex;align-items:center;gap:var(--spacing-sm);padding:var(--spacing-sm) var(--spacing-md);background:#fff;border:2px solid var(--color-border);border-radius:6px;cursor:pointer;transition:all .2s ease;min-width:80px}.mc__option:hover:not(:disabled){border-color:var(--color-accent);background:var(--color-accent-light)}.mc__option--correct{border-color:#16a34a;background:#dcfce7}.mc__option--correct:hover{background:#dcfce7}.mc__option--wrong{border-color:#dc2626;background:#fef2f2}.mc__option-label{font-size:calc(var(--font-size-small) * var(--font-scale, 1));font-weight:700;color:#dc2626;min-width:1.2em}.mc__option-content{display:flex;flex-direction:column;align-items:flex-start}.mc__option-pinyin{font-size:calc(12px * var(--font-scale, 1));color:var(--color-accent);font-style:italic}.mc__option-word{font-size:calc(var(--font-size-base) * var(--font-scale, 1));font-family:var(--font-cjk);font-weight:500;color:var(--color-text)}.mc__complete{display:flex;align-items:center;justify-content:center;gap:var(--spacing-sm);padding:var(--spacing-md);background:#dcfce7;border:2px solid #16a34a;border-radius:6px;margin-top:var(--spacing-md);animation:fadeIn .3s ease}.mc__complete-icon{font-size:24px}.mc__complete-text{font-size:calc(var(--font-size-base) * var(--font-scale, 1));font-weight:600;color:#16a34a}.section--imagedescribe .section__sentences{background:transparent}.imgdesc{padding:var(--spacing-md) 0}.imgdesc__progress{display:flex;align-items:center;gap:var(--spacing-sm);margin-bottom:var(--spacing-lg)}.imgdesc__progress-text{font-size:calc(var(--font-size-small) * var(--font-scale, 1));font-weight:600;color:var(--color-accent);min-width:2.5em}.imgdesc__progress-bar{flex:1 1;height:6px;background:var(--color-border);border-radius:3px;overflow:hidden}.imgdesc__progress-fill{height:100%;background:var(--color-accent);border-radius:3px;transition:width .3s ease}.imgdesc__grid{display:grid;grid-template-columns:1fr 1fr;grid-gap:var(--spacing-lg);gap:var(--spacing-lg)}@media (max-width:600px){.imgdesc__grid{grid-template-columns:1fr}}.imgdesc__card{border:2px solid var(--color-border);border-radius:6px;overflow:hidden;background:#fff}.imgdesc__image{width:100%;aspect-ratio:4/3;overflow:hidden;background:#f3f4f6}.imgdesc__image-img{width:100%;height:100%;object-fit:cover}.imgdesc__sentence{padding:var(--spacing-md);font-size:calc(var(--font-size-base) * var(--font-scale, 1));line-height:2;display:flex;flex-wrap:wrap;align-items:center}.imgdesc__sentence--dialogue{display:grid;grid-template-columns:2.5em auto 1fr;grid-gap:var(--spacing-xs);gap:var(--spacing-xs);align-items:start}.imgdesc__sentence--dialogue .sentence__dialogue-number{font-weight:400;color:var(--color-text-primary);text-align:center}.imgdesc__sentence--dialogue .sentence__speaker{font-weight:500;color:var(--color-accent);min-width:3em}.imgdesc__sentence--dialogue .imgdesc__text-content{display:flex;flex-wrap:wrap;align-items:center;gap:4px}.imgdesc__blank-wrapper{display:inline-flex;align-items:center;gap:2px;position:relative}.imgdesc__blank-wrapper--wrong{animation:imgdesc-shake .4s ease-in-out}@keyframes imgdesc-shake{0%,to{transform:translateX(0)}20%{transform:translateX(-4px)}40%{transform:translateX(4px)}60%{transform:translateX(-3px)}80%{transform:translateX(3px)}}.imgdesc__input{border:none;border-bottom:2px solid var(--color-border);background:transparent;font-size:inherit;font-family:inherit;width:5em;text-align:center;padding:0 var(--spacing-xs);outline:none;transition:border-color .2s}.imgdesc__input:focus{border-bottom-color:var(--color-accent)}.imgdesc__input--correct{border-bottom-color:#16a34a;color:#16a34a;font-weight:600}.imgdesc__input--wrong{border-bottom-color:#dc2626;color:#dc2626}.imgdesc__input::placeholder{color:var(--color-text-light);font-weight:400}.imgdesc__check-btn{display:inline-flex;align-items:center;justify-content:center;width:1.5em;height:1.5em;border:none;border-radius:50%;background:var(--color-accent);color:#fff;font-size:calc(var(--font-size-small) * var(--font-scale, 1));font-weight:700;cursor:pointer;padding:0;flex-shrink:0}.imgdesc__check-btn:hover{background:#2563eb}.imgdesc__complete{display:flex;align-items:center;justify-content:center;gap:var(--spacing-sm);padding:var(--spacing-lg);margin-top:var(--spacing-lg);background:#f0fdf4;border-radius:6px}.imgdesc__complete-icon{font-size:1.5em}.imgdesc__complete-text{font-size:calc(var(--font-size-base) * var(--font-scale, 1));font-weight:600;color:#16a34a}.section--activity .section__sentences{background:transparent}.tablefill{padding:var(--spacing-md)}.tablefill__table{border:2px solid var(--color-border);border-radius:6px;overflow:hidden;margin-top:var(--spacing-lg)}.tablefill__row{display:grid;grid-template-columns:repeat(auto-fit,minmax(0,1fr))}.tablefill__row--header{background:#f0fdf4;border-bottom:2px solid var(--color-border)}.tablefill__cell{padding:var(--spacing-md);text-align:center;border:none;background:none;font-family:inherit}.tablefill__cell+.tablefill__cell{border-left:1px solid var(--color-border)}.tablefill__cell--header{display:flex;flex-direction:column;align-items:center;gap:2px}.tablefill__cell-label{font-size:calc(var(--font-size-base) * var(--font-scale, 1));font-weight:600}.tablefill__cell-pinyin{font-size:calc(var(--font-size-small) * var(--font-scale, 1));color:var(--color-accent);font-style:italic}.tablefill__cell--input{min-height:3em;cursor:pointer;font-size:calc(var(--font-size-base) * var(--font-scale, 1));transition:background .2s,box-shadow .2s}.tablefill__cell--input:hover{background:#f9fafb}.tablefill__cell--selected{background:#eff6ff;box-shadow:inset 0 0 0 2px var(--color-accent)}.tablefill__cell--filled{color:#16a34a;font-weight:600}.section--bonus{margin-top:var(--spacing-xl)}.section--bonus .section__header{background:linear-gradient(135deg,#dc2626,#b91c1c);border-radius:8px 8px 0 0}.section--bonus .section__sentences{background:transparent;padding:0}.bonus__video-wrapper{border-radius:0 0 8px 8px;overflow:hidden;background:#1a1a1a;border:2px solid var(--color-border);border-top:none}.bonus__video{width:100%;display:block;max-height:400px;object-fit:contain;background:#1a1a1a}.section__header{display:inline-flex;align-items:center;gap:var(--spacing-md);margin-bottom:0;background:linear-gradient(135deg,#dc2626,#b91c1c);padding:var(--spacing-sm) var(--spacing-lg);border-radius:6px 6px 0 0;position:relative}.section__heading{margin:0;font-size:calc(var(--font-size-large) * var(--font-scale, 1));font-weight:700;color:#fff;font-family:var(--font-cjk);text-shadow:0 1px 2px rgba(0,0,0,.2)}.section__subheading{font-size:calc(var(--font-size-base) * var(--font-scale, 1));color:hsla(0,0%,100%,.9);font-weight:500;padding-left:var(--spacing-sm);border-left:2px solid hsla(0,0%,100%,.4)}.section__audio-btn{display:inline-flex;align-items:center;justify-content:center;width:28px;height:28px;padding:0;border:none;border-radius:50%;background:var(--color-accent);color:#fff;cursor:pointer;transition:all .15s ease;flex-shrink:0}.section__audio-btn:hover{background:#2563eb;transform:scale(1.05)}.section__audio-btn:disabled{cursor:wait}.section__audio-btn--playing{background:#16a34a}.section__audio-loading{width:14px;height:14px;border:2px solid hsla(0,0%,100%,.3);border-top-color:#fff;border-radius:50%;animation:spin .8s linear infinite}@keyframes spin{0%{transform:rotate(0deg)}to{transform:rotate(1turn)}}.page__audio-fab{position:fixed;bottom:80px;right:24px;width:48px;height:48px;border:none;border-radius:50%;background:var(--color-accent,#3182ce);color:#fff;cursor:pointer;display:flex;align-items:center;justify-content:center;box-shadow:0 4px 12px rgba(0,0,0,.25);transition:background-color .2s ease,transform .15s ease;z-index:80}.page__audio-fab:hover{transform:scale(1.08)}.page__audio-fab--playing{background:var(--color-accent)}.page__audio-fab:disabled{opacity:.7;cursor:not-allowed}.page__audio-fab-spinner{width:20px;height:20px;border:3px solid hsla(0,0%,100%,.3);border-top-color:#fff;border-radius:50%;animation:spin .8s linear infinite}.section__context{margin-bottom:var(--spacing-md);padding:var(--spacing-sm) var(--spacing-md);background:rgba(0,0,0,.03);border-radius:3px;font-size:calc(var(--font-size-small) * var(--font-scale, 1))}.section__context-text{margin:0 0 var(--spacing-xs) 0;color:var(--color-text);font-family:var(--font-cjk)}.section__context-pinyin{margin:0 0 var(--spacing-xs) 0;color:var(--color-accent);font-style:italic;font-size:calc(var(--font-size-small) * var(--font-scale, 1))}.section__context-translation{margin:0;color:var(--color-text-secondary);font-style:italic}.section__instruction-row{display:flex;align-items:flex-start;gap:var(--spacing-sm);margin-top:var(--spacing-sm);margin-bottom:var(--spacing-md)}.section__instruction-checkbox{color:var(--color-accent);font-size:calc(var(--font-size-small) * var(--font-scale, 1));flex-shrink:0;line-height:1.6;margin-top:.1em}.section--exercise .section__instruction-row{padding-left:var(--spacing-md)}.section__instruction{margin:0;font-size:calc(var(--font-size-small) * var(--font-scale, 1));color:var(--color-text-secondary);font-style:italic}.section__tip{margin-bottom:var(--spacing-md);padding:18px;background:#fff;border-radius:10px;box-shadow:0 2px 8px rgba(0,0,0,.1),0 6px 24px rgba(0,0,0,.06);position:relative}.section__tip-label{display:inline-block;padding:2px 8px;background:#f59e0b;color:#fff;font-size:calc(12px * var(--font-scale, 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var(--spacing-lg)}.section__images-grid-item{border-radius:6px;overflow:hidden}.section__images-grid-img{display:block;width:100%;height:auto}.sentence{display:grid;grid-template-columns:auto 1fr;grid-gap:var(--spacing-sm);gap:var(--spacing-sm);padding:var(--spacing-sm);border-radius:3px;transition:background-color .15s ease,color .15s ease;align-items:start;cursor:pointer}.sentence:not(:has(.sentence__speaker)){grid-template-columns:1fr}.sentence--active{color:var(--color-accent)}.sentence--has-audio{cursor:pointer}.sentence--playing .sentence__text,.sentence__speaker{color:var(--color-accent)}.sentence__speaker{min-width:3em;font-weight:600;white-space:nowrap}.sentence__body{display:inline-flex;align-items:flex-start;gap:var(--spacing-sm);cursor:pointer;font-family:var(--font-cjk)}.sentence__body:focus{outline:none}.sentence__text{flex:1 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svg{width:16px;height:16px}.sentence__audio-btn:hover{background:var(--color-accent-light);border-color:var(--color-accent);color:var(--color-accent)}.sentence__audio-btn:focus{outline:none}.sentence__audio-btn--playing{background:var(--color-accent);border-color:var(--color-accent);color:#fff}.sentence__audio-btn--loading{opacity:.6;cursor:wait}.sentence__audio-btn:disabled{cursor:not-allowed}.sentence__checkbox{display:inline-block;margin-right:var(--spacing-sm);font-size:1.2em;color:#dc2626;vertical-align:middle}.sentence__grammar-number{display:inline-flex;align-items:center;justify-content:center;width:1.5em;height:1.5em;background:#dc2626;color:#fff;font-size:calc(var(--font-size-small) * var(--font-scale, 1));font-weight:700;border-radius:3px;margin-right:var(--spacing-sm);flex-shrink:0;margin-top:.15em}.sentence__text-block{display:flex;flex-direction:column}.sentence__text-row{display:flex;align-items:flex-start;gap:var(--spacing-sm)}.sentence__text ruby{ruby-position:under;ruby-align:center;margin:0 .1em}.sentence__text rt{font-family:var(--font-pinyin);font-size:.6em;color:var(--color-accent);font-style:normal;font-weight:400;padding-top:.3em}.sentence__text rp{display:none}.sentence__pinyin{color:var(--color-accent);font-family:var(--font-pinyin);letter-spacing:.5px}.sentence__pinyin,.sentence__translation-inline{display:block;font-size:calc(var(--font-size-small) * var(--font-scale, 1));font-style:italic;margin-top:var(--spacing-xs)}.sentence__translation,.sentence__translation-inline{color:var(--color-text-translation)}.sentence__translation{margin-top:var(--spacing-sm);padding:var(--spacing-sm);background:var(--color-accent-light);border-radius:3px;font-size:var(--font-size-small);font-family:inherit}@media (max-width:600px){:root{--font-size-base:16px;--font-size-large:20px;--spacing-lg:16px;--spacing-xl:24px;--header-height:52px;--bottom-nav-height:48px}.page{padding:var(--spacing-md);padding-top:calc(var(--header-height) 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(max-width:600px){.flashcard-page{padding:var(--spacing-md);padding-top:calc(56px + var(--spacing-md) + env(safe-area-inset-top, 0px));padding-bottom:calc(48px + var(--spacing-md) + env(safe-area-inset-bottom, 0px))}.flashcard-page__title{font-size:1.2rem}.flashcard__chinese{font-size:2.5rem}.flashcard__card-container{max-width:320px}.flashcard__action-btn{padding:var(--spacing-sm) var(--spacing-md);font-size:.9rem}}.karaoke{min-height:100vh;display:flex;flex-direction:column;background:#0a0a0a;color:#fff}.karaoke__info{text-align:center;padding:calc(var(--header-height) + 40px + env(safe-area-inset-top, 0px)) var(--spacing-xl) var(--spacing-lg)}.karaoke__title{font-size:2rem;font-weight:700;margin:0 0 4px;color:#fff}.karaoke__pinyin{font-size:1rem;color:hsla(0,0%,100%,.5);font-style:italic;margin:0 0 8px}.karaoke__artist{font-size:.9rem;color:hsla(0,0%,100%,.4);margin:0 0 4px}.karaoke__translation{font-size:.9rem;color:hsla(0,0%,100%,.35);font-style:italic;margin:0}.karaoke__lyrics{flex:1 1;overflow-y:auto;padding:calc(var(--header-height) + 60px + env(safe-area-inset-top, 0px)) var(--spacing-xl);display:flex;flex-direction:column;gap:20px;padding-bottom:200px}.karaoke__line{font-size:1.8em;font-weight:500;text-align:center;color:hsla(0,0%,100%,.25);line-height:2;cursor:pointer}.karaoke__line--active{color:hsla(0,0%,100%,.5)}.karaoke__line--past{color:hsla(0,0%,100%,.15)}.karaoke__char{ruby-align:center;margin:0 .08em}.karaoke__rt{font-family:var(--font-pinyin);font-size:.5em;color:hsla(0,0%,100%,.35);font-weight:400;padding-bottom:.15em}.karaoke__rt--hidden{visibility:hidden}.karaoke__line--active .karaoke__rt{color:hsla(0,0%,100%,.5)}.karaoke__char--sung,.karaoke__char--sung .karaoke__rt{color:#4fc3f7}.karaoke__char--singing{color:#ffd54f}.karaoke__char--singing .karaoke__rt{color:#4fc3f7}.karaoke__controls{position:fixed;bottom:calc(44px + 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32px)}.home__lang-dropdown-item{display:block;width:100%;padding:12px 16px;min-height:44px;background:none;border:none;font-size:.9rem;font-family:inherit;color:#333;cursor:pointer;text-align:left}.home__lang-dropdown-item:hover{background:#f5f5f5}.home__lang-dropdown-item--active{color:#dc2626;font-weight:600}.home__hero-logo-img{height:64px;width:auto}.home__logo{margin:0 0 var(--spacing-sm) 0;font-size:2.5rem;font-weight:700;display:flex;align-items:center;justify-content:center;gap:var(--spacing-sm)}.home__logo-icon{font-size:2rem}.home__logo-img{height:68px;width:auto;filter:brightness(0) invert(1)}.home__tagline{margin:0 0 var(--spacing-xs) 0;font-size:1.1rem;opacity:.95}.home__user-btn{display:flex;align-items:center;gap:8px;background:hsla(0,0%,100%,.2);color:#fff;border:1px solid hsla(0,0%,100%,.4);border-radius:8px;padding:4px 12px 4px 4px;font-size:.85rem;font-weight:600;cursor:pointer;transition:background .15s 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var(--spacing-xl);text-align:center;font-family:inherit}.not-found h1{margin:0 0 var(--spacing-md) 0;color:var(--color-text)}.not-found p{margin:0 0 var(--spacing-xl) 0;color:var(--color-text-secondary)}.not-found a{display:inline-block;padding:.75rem 1.5rem;background:var(--color-accent);color:#fff;text-decoration:none;border-radius:4px;transition:background .15s ease}.not-found a:hover{background:#2c5282}.guided{--font-scale:1;position:relative;width:100%;max-width:900px;margin:0 auto;padding:var(--spacing-lg) var(--spacing-xl);padding-top:calc(var(--header-height) + var(--spacing-md) + env(safe-area-inset-top, 0px));padding-bottom:calc(var(--spacing-xl) + env(safe-area-inset-bottom, 0px));font-family:inherit;font-size:calc(var(--font-size-base) * 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#e5e7eb}.landing__nav-inner{max-width:1200px;margin:0 auto;padding:18px 32px;justify-content:space-between}.landing__nav-inner,.landing__nav-logo{display:flex;align-items:center}.landing__nav-logo-img{height:64px;width:auto}.landing__nav-links{display:flex;align-items:center;gap:32px}.landing__nav-link{font-size:1.1rem;font-weight:500;color:#4b5563;text-decoration:none;padding:4px 0;border-bottom:2px solid transparent;transition:color .15s,border-color .15s}.landing__nav-link:hover{color:#1a1a1a;border-bottom-color:var(--color-accent)}.landing__nav-right{display:flex;align-items:center;gap:12px}.landing__lang-btn{padding:6px 14px;border:1px solid #d1d5db;border-radius:6px;font-size:.85rem;color:#6b7280}.landing__lang-btn,.landing__login-btn{background:#fff;font-weight:600;cursor:pointer}.landing__login-btn{display:flex;align-items:center;gap:8px;padding:10px 24px;border:2px solid var(--color-accent);border-radius:6px;font-size:1.1rem;color:var(--color-accent);transition:background .15s,color .15s}.landing__login-btn:hover{background:var(--color-accent);color:#fff}.landing__hamburger{display:none;align-items:center;justify-content:center;flex-direction:column;gap:5px;width:36px;height:36px;padding:6px;background:none;border:none;cursor:pointer;font-size:1.4rem;color:#1a1a1a}.landing__hamburger span{display:block;height:2px;width:100%;background:#1a1a1a;border-radius:1px}.landing__mobile-menu{display:none;border-top:1px solid #e5e7eb;background:#f8f7f4;padding:12px 24px}.landing__mobile-link{display:block;padding:16px 8px;font-size:1.15rem;font-weight:600;color:#1a1a1a;text-decoration:none;border-bottom:1px solid #e5e7eb}.landing__mobile-link:last-child{border-bottom:none}.landing__mobile-link--active{color:var(--color-accent);border-bottom:3px solid var(--color-accent)}.landing__user-btn{display:flex;align-items:center;gap:8px;padding:4px 12px 4px 4px;background:#f3f4f6;border:none;border-radius:12px;cursor:pointer;font-size:.9rem;color:#333}.landing__user-avatar{width:28px;height:28px;border-radius:50%}.landing__user-name{font-weight:500}.landing__hero{text-align:center;padding:80px 24px var(--hero-padding-bottom);max-width:none;width:100%;margin:0;background:var(--color-accent);color:#fff}.landing__hero-title{font-size:2.8rem;font-weight:800;color:#fff;line-height:1.2;margin:0 0 16px;transform:translateY(250px)}.landing__hero-subtitle{font-size:1.2rem;color:hsla(0,0%,100%,.85);line-height:1.6;margin:0 0 32px}.landing__hero-cta{display:inline-flex;align-items:center;gap:10px;padding:14px 32px;background:#fff;color:#1a1a1a;border:none;border-radius:8px;font-size:1.1rem;font-weight:600;cursor:pointer;transition:transform .15s,box-shadow .2s;box-shadow:0 4px 12px rgba(0,0,0,.15)}.landing__hero-cta:hover{transform:translateY(-1px);box-shadow:0 6px 16px rgba(0,0,0,.2)}.landing__hero-visual{margin-top:48px;position:relative;height:200px}.landing__demo-card{position:absolute;text-align:left;background:#fff;border:1px solid #e5e7eb;border-radius:10px;padding:24px 32px;box-shadow:0 4px 20px rgba(0,0,0,.08);left:50%;transform:translateX(-550px) translateY(-100px)}.landing__demo-card--second{transform:translateX(-250px) translateY(275px)}.landing__demo-card--third{transform:translateX(350px) translateY(25px);white-space:nowrap}.landing__demo-highlight{background:var(--color-accent);color:#fff;padding:2px 6px;border-radius:3px;position:relative}.landing__demo-tooltip{top:-32px;color:var(--color-accent);font-size:1rem;font-style:italic;white-space:nowrap}.landing__demo-tooltip,.landing__demo-tooltip:after{position:absolute;left:50%;transform:translateX(-50%)}.landing__demo-tooltip:after{content:"";bottom:-6px;width:0;height:0;border-left:6px solid transparent;border-right:6px solid transparent;border-top:6px solid var(--color-accent)}.landing__demo-line--large{font-size:1.8rem;margin-bottom:0;color:#1a1a1a}.landing__demo-cursor{position:absolute;bottom:-24px;right:-18px;width:36px;height:36px;filter:drop-shadow(0 1px 3px rgba(0,0,0,.3))}.landing__demo-line{margin-bottom:6px}.landing__demo-chinese{font-size:1.5rem;color:#1a1a1a;font-weight:500}.landing__demo-line--pinyin{font-size:1rem;color:var(--color-accent);font-style:italic}.landing__demo-line--translation{font-size:.95rem;color:#6b7280;font-style:italic}.landing__showcase{padding:80px 24px 60px;background:#fff}.landing__showcase-content{max-width:900px;margin:0 auto;text-align:center}.landing__showcase-title{font-size:2.2rem;font-weight:700;color:#1a1a1a;margin:0 0 12px}.landing__showcase-subtitle{font-size:1.1rem;color:#6b7280;margin:0 0 48px;line-height:1.5}.landing__showcase-demo{position:relative;display:flex;flex-direction:column;align-items:center}.landing__showcase-card{background:#f5f5f0;border:1px solid #e5e5e0;border-radius:10px;padding:32px 40px;box-shadow:0 4px 20px rgba(0,0,0,.08);display:inline-block}.landing__showcase-line{font-size:1.8rem;color:#1a1a1a;white-space:nowrap}.landing__showcase-highlight{background:var(--color-accent);color:#fff;padding:2px 8px;border-radius:3px;position:relative}.landing__showcase-tooltip{position:absolute;top:-34px;left:50%;transform:translateX(-50%);color:var(--color-accent);font-size:1.1rem;font-style:italic;white-space:nowrap}.landing__showcase-tooltip:after{content:"";position:absolute;bottom:-6px;left:50%;transform:translateX(-50%);width:0;height:0;border-left:6px solid transparent;border-right:6px solid transparent;border-top:6px solid var(--color-accent)}.landing__showcase-cursor{position:absolute;bottom:-20px;right:-14px;width:28px;height:28px;filter:drop-shadow(0 1px 2px rgba(0,0,0,.2))}.landing__showcase-arrows{width:600px;height:250px;margin-top:-10px}.landing__showcase-labels{display:flex;justify-content:space-between;width:600px;margin-top:-20px}.landing__showcase-label{font-size:1.2rem;font-weight:700;color:#333;max-width:200px;line-height:1.3}.landing__hero-langs{margin-top:48px;margin-bottom:var(--hero-card-margin-bottom);transform:translateY(var(--hero-card-translateY));position:relative;z-index:1}.landing__hero-langs-inner{display:inline-flex;flex-direction:column;align-items:center;background:#1a2e1a;border-radius:14px;padding:48px;gap:28px}.landing__hero-langs-row{display:flex;justify-content:center;gap:36px}.landing__hero-lang{display:flex;flex-direction:column;align-items:center;gap:10px;text-decoration:none}.landing__hero-lang-flag{width:96px;height:64px;object-fit:cover;border-radius:6px}.landing__hero-lang-name{font-size:1rem;font-weight:600;color:#fff}.landing__hero-langs-more{font-size:1.15rem;font-weight:700;color:#fff;margin:0}.landing__section{padding:60px 24px;max-width:1000px;margin:0 auto;width:100%;box-sizing:border-box}.landing__section--gray{background:#f9fafb;max-width:none;padding-top:320px}.landing__section--gray .landing__section-title,.landing__section--gray .landing__steps{max-width:1000px;margin-left:auto;margin-right:auto}.landing__section-title{text-align:center;font-size:1.8rem;font-weight:700;color:#1a1a1a;margin:0 0 40px}.landing__languages{display:flex;gap:16px;justify-content:center;flex-wrap:wrap}.landing__lang-card{display:flex;align-items:center;gap:12px;padding:16px 28px;background:#fff;border:1px solid #e5e7eb;border-radius:8px;text-decoration:none;color:#333;transition:box-shadow .2s,transform .15s}.landing__lang-card:hover{box-shadow:0 4px 12px rgba(0,0,0,.1);transform:translateY(-2px)}.landing__lang-flag{font-size:2rem}.landing__lang-name{font-size:1.05rem;font-weight:600}.landing__lang-original{font-size:.9rem;color:#9ca3af}.landing__steps{display:grid;grid-template-columns:repeat(3,1fr);grid-gap:24px;gap:24px}.landing__step{text-align:center;padding:32px 20px;background:#fff;border-radius:10px;box-shadow:0 2px 8px rgba(0,0,0,.06)}.landing__step-icon{font-size:2.5rem;margin-bottom:12px}.landing__step-num{display:inline-flex;align-items:center;justify-content:center;width:28px;height:28px;background:var(--color-accent);color:#fff;border-radius:50%;font-size:.85rem;font-weight:700;margin-bottom:12px}.landing__step-title{font-size:1.1rem;font-weight:600;color:#1a1a1a;margin:0 0 8px}.landing__step-desc{font-size:.95rem;color:#6b7280;line-height:1.5;margin:0}.landing__features{display:grid;grid-template-columns:repeat(3,1fr);grid-gap:24px;gap:24px}.landing__feature{padding:24px;background:#fff;border:1px solid #e5e7eb;border-radius:8px;text-align:center}.landing__feature-icon{font-size:2rem;margin-bottom:12px}.landing__feature-title{font-size:1.05rem;font-weight:600;color:#1a1a1a;margin:0 0 8px}.landing__feature-desc{font-size:.9rem;color:#6b7280;line-height:1.5;margin:0}.landing__cta{text-align:center;padding:60px 24px;background:linear-gradient(135deg,#3182ce,#2563eb);color:#fff}.landing__cta-title{font-size:2rem;font-weight:700;margin:0 0 12px}.landing__cta-subtitle{font-size:1.1rem;opacity:.9;margin:0 0 28px}.landing__cta-btn{display:inline-flex;align-items:center;gap:10px;padding:14px 32px;background:#fff;color:#333;border:none;border-radius:8px;font-size:1.1rem;font-weight:600;cursor:pointer;transition:transform .15s,box-shadow .2s;box-shadow:0 4px 12px rgba(0,0,0,.15)}.landing__cta-btn:hover{transform:translateY(-1px);box-shadow:0 6px 16px rgba(0,0,0,.2)}.landing__footer{text-align:center;padding:32px 24px;background:#1a1a1a;color:#9ca3af;margin-top:auto}.landing__footer-text{margin:0;font-size:.9rem}@media (max-width:768px){.landing__hero{max-width:none;width:100%;margin:0;--hero-padding-bottom:440px;--hero-card-margin-bottom:-380px;--hero-card-translateY:200px;padding-top:260px!important;background:var(--color-accent)}.landing__hero-title{font-size:1.8rem;color:#fff;transform:translateY(20px)}.landing__hero-subtitle{font-size:1rem;color:hsla(0,0%,100%,.85)}.landing__hero-cta{background:#fff;color:#1a1a1a;box-shadow:none}.landing__hero-cta:hover{box-shadow:none;transform:none}.landing__hero-cta svg path{fill:currentColor}.landing__hero-visual{display:none}.landing__demo-chinese{color:#fff}.landing__demo-line--pinyin{color:hsla(0,0%,100%,.8)}.landing__demo-line--translation{color:hsla(0,0%,100%,.7)}.landing__hero-langs-inner{padding:24px 20px}.landing__hero-langs{margin-left:16px;margin-right:16px}.landing__hero-langs-inner{display:flex;width:100%;padding:24px 16px;gap:16px}.landing__hero-langs-row{gap:12px}.landing__hero-lang-flag{width:56px;height:38px;border-radius:4px}.landing__hero-lang-name{font-size:.85rem}.landing__hero-langs-more{font-size:1rem}.landing__features,.landing__steps{grid-template-columns:1fr;gap:16px}.landing__section{padding:40px 20px}.landing__section--gray{padding-top:115px}.landing__showcase{padding:48px 20px 40px}.landing__showcase-title{font-size:1.6rem}.landing__showcase-subtitle{font-size:1rem;margin-bottom:32px}.landing__showcase-card{padding:24px 20px}.landing__showcase-line{font-size:1.4rem}.landing__showcase-arrows{display:none}.landing__showcase-labels{flex-direction:column;width:auto;gap:16px;margin-top:32px;align-items:center}.landing__showcase-label{font-size:1rem;max-width:none}.landing__section-title{font-size:1.4rem;margin-bottom:24px}.landing__nav-links{display:none}.landing__login-btn{padding:8px 16px;font-size:.9rem;border-width:1.5px}.landing__lang-btn{padding:5px 10px;font-size:.8rem}.landing__hamburger{display:flex}.landing__mobile-menu{display:block}.landing__demo-card{padding:16px 20px}.landing__demo-chinese{font-size:1.2rem}}@media (max-width:480px){.landing__hero-title{font-size:1.5rem}.landing__languages{flex-direction:column;align-items:stretch}.landing__nav-inner{padding:10px 16px}}.paywall{position:fixed;inset:0;z-index:200;display:flex;align-items:center;justify-content:center;background:rgba(0,0,0,.5);padding:24px}.paywall__card{background:#fff;border-radius:10px;padding:40px 32px;max-width:400px;width:100%;text-align:center;box-shadow:0 8px 32px rgba(0,0,0,.2)}.paywall__title{font-size:1.3rem;font-weight:600;color:#333;margin:0 0 12px}.paywall__text{font-size:.95rem;color:#666;margin:0 0 24px;line-height:1.5}.paywall__btn{display:inline-block;padding:12px 32px;background:#dc2626;color:#fff;border:none;border-radius:6px;font-size:1rem;font-weight:600;cursor:pointer;margin-bottom:16px;text-decoration:none}.paywall__back{display:block;font-size:.9rem;color:#888;text-decoration:none}.payment{max-width:500px;margin:0 auto;padding:0 24px 60px}.payment__header{display:flex;align-items:center;padding:16px 0}.payment__logo{text-decoration:none}.payment__title{font-size:1.4rem;font-weight:600;margin:8px 0 20px;color:#222}.payment__plans{display:grid;grid-template-columns:repeat(2,1fr);grid-gap:12px;gap:12px;margin-bottom:32px}.payment__plan{position:relative;display:flex;flex-direction:column;align-items:center;gap:4px;padding:16px 12px;background:#fff;border:2px solid #e5e5e5;border-radius:12px;cursor:pointer;transition:border-color .15s}.payment__plan--selected{border-color:#dc2626;background:#fef2f2}.payment__plan-months{font-size:1.1rem;font-weight:600;color:#222}.payment__plan-price{font-size:.95rem;color:#555}.payment__plan-per-month{font-size:.8rem;color:#888}.payment__plan-badge{position:absolute;top:-8px;right:-4px;background:#dc2626;color:#fff;font-size:.7rem;font-weight:600;padding:2px 8px;border-radius:10px}.payment__section{margin-bottom:28px}.payment__section-title{font-size:1rem;font-weight:600;color:#333;margin:0 0 12px}.payment__card-info{display:flex;align-items:center;gap:12px;background:#f5f5f5;border-radius:10px;padding:14px 16px}.payment__card-number{font-size:1.2rem;font-weight:600;letter-spacing:2px;color:#222;font-feature-settings:"tnum";font-variant-numeric:tabular-nums}.payment__copy-btn{display:flex;align-items:center;justify-content:center;width:36px;height:36px;background:#fff;border:1px solid #ddd;border-radius:8px;cursor:pointer;color:#666;flex-shrink:0}.payment__card-amount{font-size:.9rem;color:#555;margin:10px 0 0}.payment__upload{display:flex;align-items:center;justify-content:center;min-height:140px;border:2px dashed #ccc;border-radius:12px;cursor:pointer;transition:border-color .15s;overflow:hidden}.payment__upload:hover{border-color:#999}.payment__upload--has-file{border-style:solid;border-color:#ddd;padding:8px}.payment__upload-placeholder{display:flex;flex-direction:column;align-items:center;gap:8px;color:#999;font-size:.9rem}.payment__preview{max-width:100%;max-height:300px;border-radius:8px;object-fit:contain}.payment__file-input{display:none}.payment__remove-file{display:block;margin:8px 0 0;background:none;border:none;color:#dc2626;font-size:.85rem;cursor:pointer;padding:0}.payment__error{color:#dc2626;font-size:.9rem;margin:0 0 16px}.payment__submit{display:flex;align-items:center;justify-content:center;width:100%;padding:14px;background:#dc2626;color:#fff;border:none;border-radius:10px;font-size:1rem;font-weight:600;cursor:pointer;min-height:48px}.payment__submit:disabled{opacity:.5;cursor:not-allowed}.payment__spinner{width:20px;height:20px;border:2px solid hsla(0,0%,100%,.3);border-top-color:#fff;border-radius:50%;animation:spin .6s linear infinite}.payment__success{display:flex;flex-direction:column;align-items:center;text-align:center;padding:60px 0;gap:16px}.payment__success-icon{margin-bottom:8px}.payment__success-title{font-size:1.3rem;font-weight:600;color:#222;margin:0}.payment__success-text{font-size:1rem;color:#666;margin:0}.payment__back-btn{display:inline-block;margin-top:16px;color:#888;text-decoration:none;font-size:.9rem}@media (max-width:600px){.payment{padding:0 16px 40px}.payment__card-number{font-size:1.05rem;letter-spacing:1px}}.admin{max-width:900px;margin:0 auto;padding:0 0 40px}.admin__loading{text-align:center;color:#999;padding:60px 0}.admin__stats{display:grid;grid-template-columns:repeat(4,1fr);grid-gap:12px;gap:12px;margin-bottom:24px}.admin__stat{background:#fff;border-radius:12px;padding:16px;text-align:center;box-shadow:0 1px 3px rgba(0,0,0,.08)}.admin__stat-value{display:block;font-size:1.5rem;font-weight:700;color:#1a1a1a}.admin__stat-label{display:block;font-size:.8rem;color:#888;margin-top:4px}.admin__tabs{display:flex;gap:4px;margin-bottom:16px}.admin__tab{flex:1 1;padding:10px 16px;border:none;background:#e8e8e8;color:#666;font-size:.95rem;font-weight:500;border-radius:8px 8px 0 0;cursor:pointer;font-family:inherit}.admin__tab--active{background:#fff;color:#4a7ab5;font-weight:600}.admin__list{display:flex;flex-direction:column;gap:12px}.admin__empty{text-align:center;color:#999;padding:40px 0}.admin__card{background:#fff;border-radius:12px;padding:16px;box-shadow:0 1px 3px rgba(0,0,0,.08);border-left:4px solid #e0e0e0}.admin__card--pending{border-left-color:#f59e0b}.admin__card--approved{border-left-color:#16a34a}.admin__card--rejected{border-left-color:#dc2626}.admin__card-header{display:flex;justify-content:space-between;align-items:flex-start;gap:8px;margin-bottom:8px}.admin__card-name{display:block;font-weight:600;font-size:.95rem;color:#1a1a1a}.admin__card-email{font-size:.9rem;color:#555;word-break:break-all}.admin__card-details{display:flex;gap:16px;font-size:.85rem;color:#888;flex-wrap:wrap}.admin__badge{display:inline-block;padding:3px 10px;border-radius:20px;font-size:.78rem;font-weight:600;white-space:nowrap}.admin__badge--pending{background:#fef3c7;color:#92400e}.admin__badge--approved{background:#dcfce7;color:#166534}.admin__badge--rejected{background:#fee2e2;color:#991b1b}.admin__badge--none{background:#f3f4f6;color:#6b7280}.admin__screenshot-wrap{margin:10px 0}.admin__screenshot{max-width:200px;max-height:150px;border-radius:8px;cursor:pointer;border:1px solid #eee;object-fit:cover}.admin__actions{display:flex;gap:8px;margin-top:12px}.admin__btn{padding:8px 20px;border:none;border-radius:8px;font-size:.9rem;font-weight:600;cursor:pointer;font-family:inherit}.admin__btn:disabled{opacity:.5;cursor:not-allowed}.admin__btn--approve{background:#16a34a;color:#fff}.admin__btn--reject{background:#fee2e2;color:#991b1b}.admin__overlay{position:fixed;inset:0;background:rgba(0,0,0,.8);display:flex;align-items:center;justify-content:center;z-index:200;cursor:pointer;padding:20px}.admin__overlay-img{max-width:90vw;max-height:90vh;border-radius:8px;object-fit:contain}@media (max-width:600px){.admin__stats{grid-template-columns:repeat(2,1fr)}.admin__card-details,.admin__card-header{flex-direction:column}.admin__card-details{gap:4px}.admin__screenshot{max-width:100%}}.admin-login{display:flex;align-items:center;justify-content:center;min-height:100vh;background:#f5f5f5;padding:20px}.admin-login__form{background:#fff;border-radius:16px;padding:40px 32px;box-shadow:0 2px 8px rgba(0,0,0,.08);width:100%;max-width:360px;text-align:center}.admin-login__title{font-size:1.5rem;font-weight:700;color:#1a1a1a;margin-bottom:24px}.admin-login__input{width:100%;padding:12px 16px;border:2px solid #e0e0e0;border-radius:10px;font-size:1rem;font-family:inherit;outline:none;box-sizing:border-box}.admin-login__input:focus{border-color:#4a7ab5}.admin-login__error{color:#dc2626;font-size:.85rem;margin-top:8px}.admin-login__btn{width:100%;margin-top:16px;padding:12px;background:#4a7ab5;color:#fff;border:none;border-radius:10px;font-size:1rem;font-weight:600;cursor:pointer;font-family:inherit}.admin-login__btn:disabled{opacity:.5;cursor:not-allowed}