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@media(max-width:1050px){.sidebar{width:218px}.main-area{margin-left:218px}.content-wrap{padding:30px 28px}}@media(max-width:760px){.sidebar{transform:translateX(-102%);transition:transform .25s;box-shadow:8px 0 25px #18261a18}.sidebar.sidebar-open{transform:translateX(0)}.main-area{margin:0}.mobile-header{height:58px;padding:0 17px;display:flex;align-items:center;gap:11px;border-bottom:1px solid var(--line);position:sticky;top:0;background:#f8f6eff2;backdrop-filter:blur(10px);z-index:6}.mobile-header .brand{font-size:12px}.mobile-header .brand-mark{width:30px;height:30px;font-size:17px}.menu-button{border:0;background:none;font-size:19px;padding:4px}.mobile-user{margin-left:auto;max-width:100px;overflow:hidden;text-overflow:ellipsis;font-size:9px;color:#798178}.content-wrap{padding:24px 17px 18px}.page-heading{align-items:start;margin-bottom:18px}.page-heading h1{font-size:25px}.book-note{font-size:8px;max-width:110px}.welcome-hero{min-height:260px;padding:25px 22px;grid-template-columns:1fr}.welcome-copy{max-width:100%}.welcome-hero h2{font-size:36px}.welcome-hero p{max-width:70%}.hero-orbit{position:absolute;right:-36px;bottom:-48px;transform:scale(.63);opacity:.75}.orbit-label{display:none}.stats-row{gap:6px;margin:11px 0 29px}.stat-card{padding:9px 7px;gap:6px;align-items:start}.stat-icon{width:28px;height:28px;border-radius:9px;font-size:12px}.stat-card b{font-size:15px}.stat-card small{font-size:7px;line-height:1.35}.section-heading h2{font-size:19px}.chapter-grid,.unit-grid{grid-template-columns:1fr}.chapter-card{padding:15px}.chapter-card h3{font-size:21px}.continue-card{padding:14px}.site-footer{gap:12px;flex-direction:column}.chapter-hero{padding:26px 23px;min-height:180px}.chapter-hero h2{font-size:30px}.chapter-ornament{right:-9px;font-size:110px}.unit-heading{gap:11px}.unit-badge{width:48px;height:48px;border-radius:13px;font-size:16px}.unit-heading h2{font-size:21px}.skill-tabs{grid-template-columns:repeat(2,1fr)}.skill-tab{padding:8px}.lesson-panel{padding:15px 13px}.panel-topline{display:block}.zh-hint{display:block;margin-top:3px}.flashcard{min-height:205px}.flashcard-word{font-size:34px}.card-controls{gap:7px;flex-wrap:wrap}.card-count{order:-1;width:100%;text-align:center}.soft-button,.card-controls .primary-button{font-size:8px;padding:8px}.example-grid{grid-template-columns:1fr}.audio-card audio{width:100%}.word-collection{grid-template-columns:repeat(2,1fr)}.collection-word{padding:11px}.practice-form{grid-template-columns:1fr}.practice-form .primary-button{justify-self:end}.speaking-actions{align-items:flex-start;gap:8px}.book-note{padding-top:6px}}@media(max-width:390px){.stats-row{grid-template-columns:1fr}.stat-card{align-items:center}.stat-card small{font-size:8px}.book-note{display:none}.word-collection{grid-template-columns:1fr}.welcome-hero p{max-width:90%}}