:root{--navy:#17324d;--ink:#1e2a35;--muted:#687787;--line:#dfe6ed;--surface:#f5f8fb;--blue:#1769d2;--cyan:#eaf5ff;--orange:#e88a2b;--green:#168558;--red:#bc4a45;--shadow:0 12px 30px rgba(18,43,66,.09)}*{box-sizing:border-box}html,body{margin:0;background:#fff;color:var(--ink);font-family:Inter,"PingFang SC","Microsoft YaHei",sans-serif}button,input,textarea{font:inherit}button{cursor:pointer}body{min-height:100vh}.app-hidden{display:none}.access-gate{position:fixed;inset:0;z-index:100;background:var(--navy);display:grid;place-items:center;padding:20px}.access-gate.hidden{display:none}.access-panel{width:min(100%,430px);background:#fff;padding:38px 32px 30px;box-shadow:var(--shadow)}.brand-mark{width:42px;height:42px;background:var(--orange);color:#fff;display:grid;place-items:center;font-weight:900;letter-spacing:1px}.access-panel .brand-mark{margin-bottom:26px}.eyebrow,.card-kicker{font-size:11px;letter-spacing:1.3px;text-transform:uppercase;font-weight:900;color:var(--blue)}.access-panel h1{font-size:36px;line-height:1.1;margin:12px 0}.access-panel p{color:var(--muted);line-height:1.7;font-size:14px}.access-form{display:grid;gap:9px;margin-top:28px}.access-form label,.notes-editor label{font-size:12px;font-weight:900}.access-form input{height:48px;border:1px solid var(--line);padding:0 13px;outline:0}.access-form input:focus{border-color:var(--blue)}.access-error{min-height:18px;color:var(--red);font-size:12px}.access-footnote{font-size:11px;color:var(--muted);margin-top:20px}.topbar{height:74px;background:#fff;border-bottom:1px solid var(--line);display:flex;align-items:center;justify-content:space-between;padding:0 30px;position:sticky;top:0;z-index:30}.brand-lockup{display:flex;align-items:center;gap:12px}.topbar .brand-mark{width:38px;height:38px}.brand-name{font-weight:900;font-size:15px}.brand-sub{color:var(--muted);font-size:11px;margin-top:3px}.player-status{display:flex;gap:9px;align-items:center}.player-status strong,.player-status span{display:block}.player-status strong{font-size:12px}.player-status div span{color:var(--muted);font-size:11px;margin-top:2px}.level-badge{width:30px;height:30px;background:var(--cyan);color:var(--blue);display:grid;place-items:center;font-size:11px;font-weight:900}.app-shell{display:grid;grid-template-columns:210px minmax(0,1fr);min-height:calc(100vh - 74px)}.desktop-nav{border-right:1px solid var(--line);padding:32px 18px;background:#fbfcfd}.nav-caption{font-size:11px;color:var(--muted);font-weight:900;margin:0 12px 17px}.nav-button{width:100%;border:0;background:transparent;color:var(--muted);text-align:left;padding:11px 12px;display:flex;gap:10px;align-items:center;font-size:13px;font-weight:800}.nav-button span{font-size:10px;color:#9aa8b5}.nav-button:hover,.nav-button.active{color:var(--blue);background:var(--cyan)}.nav-button.active span{color:var(--blue)}.nav-rule{height:1px;background:var(--line);margin:25px 12px}.nav-mini{display:grid;gap:7px;padding:0 12px}.nav-mini span{font-size:10px;color:var(--muted)}.nav-mini strong{font-size:12px;line-height:1.5}.main-content{max-width:1040px;width:100%;padding:0 58px 80px}.view{display:none;padding-top:34px}.view.active{display:block}.mobile-progress{display:none}.welcome-block{max-width:700px;padding-top:10px}.welcome-block h1{font-size:clamp(38px,5vw,66px);line-height:1.04;margin:16px 0 0;letter-spacing:-1px}.welcome-block h1 em{font-style:normal;color:var(--blue)}.welcome-block p{max-width:650px;color:var(--muted);font-size:16px;line-height:1.75;margin-top:20px}.starter-card{background:var(--navy);color:#fff;padding:23px 24px 25px;margin-top:34px;display:grid;gap:18px}.starter-card .card-kicker{color:#a7d6ff}.starter-card h2{font-size:25px;margin:9px 0 0}.memory-chain{display:flex;align-items:center;gap:8px;overflow:auto;white-space:nowrap}.memory-chain span{background:rgba(255,255,255,.12);padding:8px 10px;font-size:12px}.memory-chain b{color:#a7d6ff}.primary-button,.secondary-button,.outline-button{border:0;min-height:43px;padding:0 16px;font-weight:900;font-size:13px;display:inline-flex;align-items:center;justify-content:center;gap:14px;transition:.15s ease}.primary-button{background:var(--blue);color:#fff}.primary-button:hover{background:#0e56b2;transform:translateY(-1px)}.primary-button span{font-size:18px}.primary-button.wide{width:100%}.secondary-button{background:var(--cyan);color:var(--blue);border:1px solid #cbe4fb}.secondary-button:hover{background:#dff0ff}.outline-button{background:#fff;color:var(--blue);border:1px solid var(--blue)}.outline-button:hover{background:var(--cyan)}.section-heading,.page-heading{display:flex;justify-content:space-between;gap:18px;align-items:end}.section-heading{margin-top:45px}.section-heading h2{font-size:26px;margin:10px 0 0}.small-stat{display:flex;gap:6px;align-items:baseline;color:var(--muted);font-size:11px;white-space:nowrap}.small-stat strong{color:var(--ink);font-size:28px}.model-grid{display:grid;grid-template-columns:repeat(5,minmax(0,1fr));gap:10px;margin-top:18px}.model-card{min-height:165px;text-align:left;border:1px solid var(--line);background:#fff;padding:15px;display:flex;flex-direction:column;gap:8px;transition:.15s ease}.model-card:hover,.model-card.learned{border-color:var(--blue);box-shadow:var(--shadow);transform:translateY(-2px)}.model-code,.product-code{font-size:12px;font-weight:900;color:var(--blue);letter-spacing:.7px}.model-card strong{font-size:14px;line-height:1.45}.model-card span:not(.model-code){font-size:11px;line-height:1.55;color:var(--muted);margin-top:auto}.model-card b{font-size:10px;color:var(--blue)}.mnemonic-strip{border-top:1px solid var(--line);border-bottom:1px solid var(--line);padding:23px 0;margin-top:38px}.mnemonic-strip strong{display:block;font-size:25px;letter-spacing:3px;margin-top:10px}.mnemonic-strip p{color:var(--muted);font-size:13px;line-height:1.6;margin:8px 0 0}.home-actions{display:flex;gap:10px;margin-top:23px}.page-heading{align-items:start;padding-bottom:25px;border-bottom:1px solid var(--line)}.page-heading h1{font-size:clamp(32px,4vw,50px);line-height:1.08;margin:13px 0 0}.page-heading p{color:var(--muted);line-height:1.7;font-size:14px;max-width:680px;margin-top:13px}.filter-scroller{display:flex;gap:8px;overflow:auto;padding:18px 0 3px}.filter-button{border:1px solid var(--line);background:#fff;color:var(--muted);padding:8px 14px;font-size:12px;white-space:nowrap}.filter-button.active{color:var(--blue);border-color:var(--blue);background:var(--cyan);font-weight:900}.product-list{display:grid;gap:14px;margin-top:16px}.product-item{display:grid;grid-template-columns:220px minmax(0,1fr);border:1px solid var(--line);background:#fff;box-shadow:0 5px 16px rgba(20,41,60,.04)}.product-media{min-height:255px;position:relative;background:#e9eef3}.product-media img{width:100%;height:100%;object-fit:cover;display:block}.product-media>span{position:absolute;left:10px;top:10px;background:var(--navy);color:#fff;padding:5px 8px;font-size:10px;font-weight:900}.product-body{padding:19px 21px;display:flex;flex-direction:column;gap:8px}.product-top{display:flex;justify-content:space-between;align-items:center}.product-status{font-size:10px;color:var(--muted)}.product-status.done{color:var(--green);font-weight:900}.product-body h3{font-size:21px;margin:1px 0 2px}.product-line,.product-detail p{font-size:13px;line-height:1.6;color:var(--muted);margin:0}.product-line b,.product-detail b{color:var(--ink);margin-right:6px}.product-detail{border-top:1px dashed var(--line);padding-top:9px;margin-top:3px}.memory-tip{color:var(--blue)!important;font-weight:800}.learn-button{align-self:flex-start;border:0;background:var(--cyan);color:var(--blue);padding:9px 11px;font-size:11px;font-weight:900;margin-top:2px}.learn-button span{margin-left:8px;color:var(--orange)}.quiz-card{max-width:760px;border:1px solid var(--line);padding:24px;margin-top:24px}.quiz-meta{display:flex;justify-content:space-between;color:var(--muted);font-size:11px}.quiz-card h2{font-size:26px;line-height:1.4;margin:20px 0}.quiz-options,.practice-options{display:grid;gap:10px}.quiz-option,.practice-option{border:1px solid var(--line);background:var(--surface);padding:14px;text-align:left;display:flex;gap:12px;align-items:start;font-size:14px;line-height:1.55}.quiz-option:hover,.practice-option:hover{border-color:var(--blue);background:var(--cyan)}.quiz-option b,.practice-option b{width:22px;height:22px;background:#fff;color:var(--blue);display:grid;place-items:center;font-size:11px;flex:0 0 auto}.quiz-option.correct,.practice-option.correct{border-color:var(--green);background:#e9f8f0}.quiz-option.wrong,.practice-option.wrong{border-color:var(--red);background:#fff0ee}.quiz-feedback,.practice-feedback{min-height:43px;color:var(--muted);font-size:13px;line-height:1.65;margin-top:15px}.quiz-feedback.good,.practice-feedback.good{color:var(--green)}.quiz-feedback.bad,.practice-feedback.bad{color:var(--red)}.quiz-next,.practice-next{display:none;margin-top:4px}.quiz-next.visible,.practice-next.visible{display:inline-flex}.quiz-result,.practice-complete{text-align:center;padding:30px 10px}.result-icon{width:44px;height:44px;background:#e7f7ef;color:var(--green);display:grid;place-items:center;font-size:22px;font-weight:900;margin:0 auto 13px}.quiz-result h2,.practice-complete h2{font-size:28px;margin:0}.quiz-result p,.practice-complete p{color:var(--muted);line-height:1.7;font-size:14px;max-width:470px;margin:12px auto 20px}.practice-list{display:grid;grid-template-columns:repeat(4,1fr);gap:9px;margin-top:22px}.practice-choice{border:1px solid var(--line);background:#fff;text-align:left;padding:13px;display:grid;gap:6px}.practice-choice strong{font-size:13px;line-height:1.4}.practice-choice span{color:var(--muted);font-size:11px}.practice-choice.active{border-color:var(--blue);background:var(--cyan)}.practice-panel{max-width:760px;margin-top:17px;border:1px solid var(--line);padding:22px}.scenario-head h2{font-size:26px;margin:10px 0 8px}.scenario-head p{font-size:13px;color:var(--muted);line-height:1.7;margin:0}.scenario-target{display:grid;gap:5px;background:var(--surface);padding:12px 13px;margin:18px 0}.scenario-target b{font-size:10px;color:var(--blue)}.scenario-target span{font-size:15px;font-weight:900}.notes-editor{max-width:760px;display:grid;gap:10px;margin-top:25px}.notes-editor textarea{width:100%;min-height:160px;border:1px solid var(--line);padding:13px;line-height:1.7;resize:vertical;outline:0}.notes-editor textarea:focus{border-color:var(--blue)}.saved-notes{max-width:760px;margin-top:28px;border-top:1px solid var(--line)}.note-entry{padding:14px 0;border-bottom:1px solid var(--line)}.note-entry time{display:block;color:var(--blue);font-size:10px;font-weight:900;margin-bottom:7px}.note-entry p{font-size:13px;line-height:1.7;white-space:pre-wrap;margin:0}.empty-state{padding:26px 0;color:var(--muted);font-size:13px}.mobile-nav{display:none}.toast{position:fixed;z-index:90;bottom:24px;left:50%;transform:translate(-50%,20px);background:var(--navy);color:#fff;padding:11px 16px;font-size:12px;opacity:0;pointer-events:none;transition:.2s}.toast.show{opacity:1;transform:translate(-50%,0)}
@media(max-width:980px){.app-shell{display:block}.desktop-nav{display:none}.main-content{padding:0 22px 92px}.mobile-nav{position:fixed;display:grid;grid-template-columns:repeat(5,1fr);left:0;right:0;bottom:0;background:#fff;border-top:1px solid var(--line);z-index:30;padding-bottom:env(safe-area-inset-bottom)}.mobile-nav-button{border:0;background:#fff;color:var(--muted);padding:8px 3px 7px;font-size:10px;display:grid;gap:3px;place-items:center}.mobile-nav-button span{font-size:19px;line-height:1}.mobile-nav-button.active{color:var(--blue);font-weight:900}.model-grid{grid-template-columns:repeat(3,minmax(0,1fr))}.practice-list{grid-template-columns:repeat(2,1fr)}}
@media(max-width:620px){.topbar{height:62px;padding:0 15px}.topbar .brand-mark{width:35px;height:35px}.brand-sub{display:none}.player-status strong{font-size:11px}.level-badge{width:28px;height:28px}.main-content{padding:0 15px 90px}.view{padding-top:22px}.mobile-progress{display:flex;align-items:end;gap:13px;padding:4px 0 18px}.mobile-progress>div:first-child{display:grid;gap:3px;min-width:82px}.mobile-progress span{color:var(--muted);font-size:10px}.mobile-progress strong{font-size:13px}.progress-track{height:5px;background:var(--surface);flex:1}.progress-track i{display:block;height:100%;background:var(--orange);width:0}.welcome-block h1{font-size:39px;letter-spacing:-.5px}.welcome-block p{font-size:15px;margin-top:16px}.starter-card{padding:20px 17px;margin-top:25px}.starter-card h2{font-size:22px}.memory-chain{gap:6px}.memory-chain span{padding:7px 8px;font-size:11px}.section-heading{margin-top:34px}.section-heading h2{font-size:23px}.model-grid{grid-template-columns:repeat(2,minmax(0,1fr));gap:8px}.model-card{min-height:150px;padding:12px}.model-card strong{font-size:13px}.mnemonic-strip{margin-top:28px;padding:18px 0}.mnemonic-strip strong{font-size:21px;letter-spacing:2px}.home-actions{display:grid;grid-template-columns:1fr 1fr}.page-heading{flex-direction:column;gap:12px;padding-bottom:19px}.page-heading h1{font-size:33px}.page-heading p{font-size:13px}.product-item{grid-template-columns:110px minmax(0,1fr)}.product-media{min-height:245px}.product-body{padding:13px 12px;gap:6px}.product-body h3{font-size:17px}.product-line,.product-detail p{font-size:11px;line-height:1.55}.product-detail{padding-top:7px}.learn-button{font-size:10px;padding:8px 9px}.quiz-card{padding:18px 15px;margin-top:17px}.quiz-card h2{font-size:22px;margin:16px 0}.quiz-option,.practice-option{padding:12px;font-size:13px}.practice-list{grid-template-columns:1fr 1fr;gap:7px}.practice-choice{padding:11px 10px}.practice-choice strong{font-size:12px}.practice-panel{padding:17px 14px}.scenario-head h2{font-size:22px}.access-panel{padding:30px 23px 25px}.access-panel h1{font-size:32px}}