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0;display:flex}.site-footer-zh{font-family:var(--font-body);color:var(--ink);font-size:.95rem;font-weight:600}.site-footer-en{font-family:var(--font-display);letter-spacing:.12em;text-transform:uppercase;color:var(--muted);font-size:.78rem;font-weight:700}.site-footer-nav{flex-wrap:wrap;gap:.35rem 1.1rem;display:flex}.site-footer-nav a{color:var(--muted);border-bottom:1px solid #0000;font-size:.88rem;font-weight:500;text-decoration:none;transition:color .15s,border-color .15s}.site-footer-nav a:hover{color:var(--sign-deep);border-bottom-color:var(--sign)}@supports (color:color-mix(in lab, red, red)){.site-footer-nav a:hover{border-bottom-color:color-mix(in srgb, var(--sign) 45%, transparent)}}.site-footer-copy{color:var(--muted);width:100%;margin:0;font-size:.8rem}@media (min-width:640px){.site-footer-copy{width:auto;margin-left:.5rem}}.legal-updated{color:var(--muted);margin:.85rem 0 0!important;font-size:.85rem!important}.legal-doc{font-family:var(--font-ui);color:var(--text);line-height:1.65}.legal-doc section+section{border-top:1px solid var(--line);margin-top:2rem;padding-top:1.75rem}.legal-doc h2{font-family:var(--font-display);letter-spacing:.04em;text-transform:uppercase;color:var(--ink);margin:0 0 .65rem;font-size:1.15rem;font-weight:700}.legal-doc h3{font-family:var(--font-ui);color:var(--ink);margin:1.15rem 0 .45rem;font-size:.98rem;font-weight:600}.legal-doc p{max-width:62ch;margin:0 0 .75rem}.legal-doc ul{max-width:62ch;margin:0 0 .85rem;padding-left:1.2rem}.legal-doc li{margin-bottom:.4rem}.legal-doc li::marker{color:var(--sign)}.legal-doc a{color:var(--sign-deep);text-underline-offset:.15em;text-decoration:underline;text-decoration-thickness:1px}.legal-doc a:hover{color:var(--jade)}.auth-footnote a{color:var(--sign-deep);text-underline-offset:.12em;text-decoration:underline}.account-panel{border-top:1px solid var(--line);margin-top:1.75rem;padding-top:1.5rem}.account-panel h2{font-family:var(--font-display);letter-spacing:.04em;text-transform:uppercase;color:var(--ink);margin:0 0 .5rem;font-size:1.05rem;font-weight:700}.account-help{max-width:52ch;font-family:var(--font-ui);color:var(--muted);margin:0 0 .9rem;font-size:.95rem;line-height:1.55}.account-help a{color:var(--sign-deep);text-underline-offset:.12em;text-decoration:underline}.account-meta{font-family:var(--font-ui);gap:.55rem;margin:0;padding:0;font-size:.95rem;list-style:none;display:grid}.account-meta li{gap:.15rem;display:grid}.account-meta-label{letter-spacing:.06em;text-transform:uppercase;color:var(--muted);font-size:.78rem;font-weight:600}.account-confirm{gap:.4rem;max-width:18rem;margin-bottom:.9rem;display:grid}.account-actions{flex-wrap:wrap;gap:.65rem;display:flex}.account-danger h2{color:var(--coral)}.account-msg{font-family:var(--font-ui);color:var(--sign-deep);margin:1.25rem 0 0;font-size:.95rem}.account-error{font-family:var(--font-ui);color:var(--coral);margin:1rem 0 0;font-size:.95rem}.nav-auth a.nav-user{text-decoration:none}.theme-toggle{border:2px solid var(--sign);align-items:center;gap:.35rem;display:inline-flex}@supports (color:color-mix(in lab, red, red)){.theme-toggle{border:2px solid color-mix(in srgb, var(--sign) 35%, transparent)}}.theme-toggle{background:var(--surface);color:var(--ink);cursor:pointer;font-family:var(--font-display);letter-spacing:.08em;text-transform:uppercase;border-radius:.2rem;padding:.28rem .55rem;transition:border-color .2s,box-shadow .2s,background .2s,color .2s}.theme-toggle:hover{border-color:var(--sign);box-shadow:var(--glow-sign)}.theme-toggle-glyph{font-family:var(--font-body);color:var(--neon-pink);font-size:.95rem;font-weight:700;line-height:1}.theme-toggle-label{color:var(--muted);font-size:.68rem;font-weight:700}[data-theme=dark] .theme-toggle{border-color:var(--neon-pink)}@supports (color:color-mix(in lab, red, red)){[data-theme=dark] .theme-toggle{border-color:color-mix(in srgb, var(--neon-pink) 55%, transparent)}}[data-theme=dark] .theme-toggle{background:#0c0e16eb;box-shadow:inset 0 0 0 1px #ff3d6e29,0 0 12px #ff3d6e1f}[data-theme=dark] .theme-toggle:hover{border-color:var(--neon-pink);box-shadow:var(--glow-pink)}[data-theme=dark] .theme-toggle-glyph{text-shadow:0 0 10px #ff3d6ebf;animation:5.5s steps(2,end) infinite neon-flicker}[data-theme=dark] .site-nav{background:linear-gradient(#121620f5,#0a0c12eb);border-bottom-color:#0000;box-shadow:0 10px 40px #00000073}[data-theme=dark] .site-nav-neon{background:linear-gradient(90deg, var(--neon-pink) 0%, var(--amber) 28%, var(--sign) 58%, var(--neon-cyan) 100%);height:3px;animation:4.8s ease-in-out infinite neon-tube-pulse;display:block;position:absolute;inset:auto 0 0;box-shadow:0 0 10px #ff3d6e73,0 0 18px #1fd98a40,0 0 22px #3ecfff33}[data-theme=dark] .site-nav:after{display:none}[data-theme=dark] .brand-glyph{color:var(--sign);border-color:var(--sign);box-shadow:0 0 0 2px #05070c, inset 0 0 12px #1fd98a2e, var(--glow-sign);background:#07110c}[data-theme=dark] .brand-word-zh{color:var(--sign);text-shadow:0 0 12px #1fd98a59}[data-theme=dark] .brand-word-en{color:var(--neon-pink);text-shadow:0 0 10px #ff3d6e59}[data-theme=dark] .nav-link:hover{color:var(--sign-bright);text-shadow:0 0 10px #1fd98a59}[data-theme=dark] .nav-link.is-active{background:var(--sign);color:#06110c;box-shadow:inset 0 0 0 1px #ffffff24,0 0 16px #1fd98a66}[data-theme=dark] .nav-signin{color:var(--sign);text-shadow:0 0 10px #1fd98a59}[data-theme=dark] .hero{color:var(--ink);box-shadow:inset 0 0 0 2px #05070c, inset 0 0 0 5px var(--sign), inset 0 0 0 7px #05070c, inset 0 0 0 9px var(--neon-pink), 0 0 40px #1fd98a1f, 0 24px 60px #0000008c;background:radial-gradient(70% 55% at 18% 28%,#1fd98a29,#0000 58%),radial-gradient(45% 40% at 88% 78%,#ff3d6e1f,#0000 55%),radial-gradient(35% 30% at 70% 18%,#3ecfff14,#0000 50%),linear-gradient(165deg,#0a2218 0%,#08131c 48%,#090b12 100%);border-radius:.15rem}@supports (color:color-mix(in lab, red, red)){[data-theme=dark] .hero{box-shadow:inset 0 0 0 2px #05070c, inset 0 0 0 5px color-mix(in srgb, var(--sign) 55%, #05070c), inset 0 0 0 7px #05070c, inset 0 0 0 9px color-mix(in srgb, var(--neon-pink) 45%, #05070c), 0 0 40px #1fd98a1f, 0 24px 60px #0000008c}}[data-theme=dark] .hero-neon-rain{opacity:.18;background-image:repeating-linear-gradient(-18deg,#0000,#0000 10px,#f7f1e809 10px 11px);background-size:24px 48px;animation:7s linear infinite neon-rain;display:block;position:absolute;inset:0;-webkit-mask-image:linear-gradient(#0000,#000 30% 70%,#0000);mask-image:linear-gradient(#0000,#000 30% 70%,#0000)}[data-theme=dark] .hero-neon-tube{pointer-events:none;border-radius:999px;display:block;position:absolute}[data-theme=dark] .hero-neon-tube-jade{background:var(--sign);width:4px;animation:3.6s ease-in-out infinite neon-tube-pulse;top:12%;bottom:14%;left:1.1rem;box-shadow:0 0 8px #1fd98acc,0 0 22px #1fd98a66}[data-theme=dark] .hero-neon-tube-pink{background:var(--neon-pink);width:3px;animation:4.2s ease-in-out infinite reverse neon-tube-pulse;top:18%;bottom:22%;right:1.1rem;box-shadow:0 0 8px #ff3d6ebf,0 0 20px #ff3d6e59}[data-theme=dark] .hero-vertical-sign{writing-mode:vertical-rl;font-family:var(--font-body);letter-spacing:.35em;color:var(--neon-pink);text-shadow:0 0 12px #ff3d6e8c;opacity:.85;font-size:.95rem;font-weight:700;display:block;position:absolute;top:18%;right:clamp(1.6rem,4vw,3rem)}[data-theme=dark] .hero-neon-tag{border:1px solid var(--amber);width:fit-content;margin:0 0 .15rem;padding:.22rem .55rem;display:inline-block}@supports (color:color-mix(in lab, red, red)){[data-theme=dark] .hero-neon-tag{border:1px solid color-mix(in srgb, var(--amber) 55%, transparent)}}[data-theme=dark] .hero-neon-tag{color:var(--amber);font-family:var(--font-display);letter-spacing:.16em;text-transform:uppercase;background:#ffb70314;border-radius:.12rem;font-size:.68rem;font-weight:700;box-shadow:0 0 14px #ffb70326}[data-theme=dark] .hero-brand{box-shadow:none;border-bottom:none;border:1px solid var(--sign);background:#05070c73;gap:.05rem;padding:.35rem .7rem .45rem}@supports (color:color-mix(in lab, red, red)){[data-theme=dark] .hero-brand{border:1px solid color-mix(in srgb, var(--sign) 35%, transparent)}}[data-theme=dark] .hero-brand{border-left:3px solid var(--neon-pink);box-shadow:0 0 0 1px #1fd98a1f,0 0 28px #1fd98a1f}[data-theme=dark] .hero-brand-zh{color:var(--sign);text-shadow:0 0 10px #1fd98a8c,0 0 28px #1fd98a40}[data-theme=dark] .hero-brand-en{color:var(--neon-pink);text-shadow:0 0 10px #ff3d6e80,0 0 24px #ff3d6e38}[data-theme=dark] .hero h1{color:#f7f1e8;text-shadow:0 2px 18px #0000008c}[data-theme=dark] .hero-lede{color:#ebe4d8cc}[data-theme=dark] .hero-watermark{color:#1fd98a0f;text-shadow:0 0 60px #1fd98a26}[data-theme=dark] .hero-grid{opacity:.035}[data-theme=dark] .hero .btn-primary{background:var(--sign);color:#06110c;border-color:var(--sign-bright);box-shadow:0 0 16px #1fd98a66,0 8px 22px #00000073}[data-theme=dark] .hero .btn-primary:hover{background:var(--sign-bright);color:#06110c;box-shadow:0 0 26px #1fd98a80,0 12px 28px #00000080}[data-theme=dark] .hero .btn-secondary{border-color:var(--neon-cyan);background:#05070c73}@supports (color:color-mix(in lab, red, red)){[data-theme=dark] .hero .btn-secondary{border-color:color-mix(in srgb, var(--neon-cyan) 55%, transparent)}}[data-theme=dark] .hero .btn-secondary{color:var(--neon-cyan);box-shadow:0 0 14px #3ecfff1f}[data-theme=dark] .hero .btn-secondary:hover{border-color:var(--neon-cyan);color:#f7f1e8;box-shadow:var(--glow-cyan);background:#3ecfff1f}[data-theme=dark] .home-band{border-top:3px solid #0000;border-image:linear-gradient(90deg, var(--neon-pink), var(--sign), var(--neon-cyan)) 1;background:linear-gradient(180deg, #ff3d6e0d, transparent 28%), linear-gradient(180deg, var(--band-top) 0%, var(--band-bottom) 100%)}[data-theme=dark] .home-path{border-top-color:var(--neon-cyan)}@supports (color:color-mix(in lab, red, red)){[data-theme=dark] .home-path{border-top-color:color-mix(in srgb, var(--neon-cyan) 45%, transparent)}}[data-theme=dark] .home-path:hover{color:var(--neon-cyan);text-shadow:0 0 12px #3ecfff59}[data-theme=dark] .eyebrow{color:var(--neon-pink);text-shadow:0 0 10px #ff3d6e59;letter-spacing:.18em}[data-theme=dark] .learn-section-advanced .eyebrow{color:var(--route);text-shadow:0 0 10px #3ecfff59}[data-theme=dark] .section-head h1,[data-theme=dark] .learn-section-head h2{text-shadow:0 0 24px #1fd98a1f}[data-theme=dark] .btn-primary{color:#06110c;box-shadow:0 0 14px #1fd98a59,0 8px 20px #00000073}[data-theme=dark] .btn-primary:hover{box-shadow:0 0 22px #1fd98a73,0 12px 28px #00000080}[data-theme=dark] .btn-secondary{color:var(--sign-bright);border-color:var(--sign);background:#141822d9}@supports (color:color-mix(in lab, red, red)){[data-theme=dark] .btn-secondary{border-color:color-mix(in srgb, var(--sign) 55%, transparent)}}[data-theme=dark] .lesson-neon-bar{background:linear-gradient(90deg, transparent, var(--sign) 18%, var(--sign-bright) 50%, var(--sign) 82%, transparent);border-radius:999px;height:3px;display:block;position:absolute;top:.55rem;left:.85rem;right:.85rem;box-shadow:0 0 10px #1fd98a8c}[data-theme=dark] .lesson-link{background:linear-gradient(180deg, #1fd98a14, transparent 40%), linear-gradient(135deg, #ffffff05, transparent 40%), var(--surface);border-color:var(--sign);padding-top:1.35rem;overflow:hidden}@supports (color:color-mix(in lab, red, red)){[data-theme=dark] .lesson-link{border-color:color-mix(in srgb, var(--sign) 65%, #0a0c12)}}[data-theme=dark] .lesson-link{box-shadow:0 0 0 2px #0a0c12, 0 0 0 4px var(--sign), 0 0 22px #1fd98a24, var(--shadow-soft)}@supports (color:color-mix(in lab, red, red)){[data-theme=dark] .lesson-link{box-shadow:0 0 0 2px #0a0c12, 0 0 0 4px color-mix(in srgb, var(--sign) 55%, #0a0c12), 0 0 22px #1fd98a24, var(--shadow-soft)}}[data-theme=dark] .lesson-link:before,[data-theme=dark] .lesson-link:after{content:"";border:1.5px solid var(--amber);width:.45rem;height:.45rem;position:absolute}@supports (color:color-mix(in lab, red, red)){[data-theme=dark] .lesson-link:before,[data-theme=dark] .lesson-link:after{border:1.5px solid color-mix(in srgb, var(--amber) 70%, transparent)}}[data-theme=dark] .lesson-link:before,[data-theme=dark] .lesson-link:after{opacity:.7}[data-theme=dark] .lesson-link:before{border-bottom:0;border-right:0;top:.45rem;left:.45rem}[data-theme=dark] .lesson-link:after{border-top:0;border-left:0;bottom:.45rem;right:.45rem}[data-theme=dark] .lesson-link:hover{box-shadow:0 0 0 2px #0a0c12, 0 0 0 4px var(--sign-bright), 0 0 32px #1fd98a52, 0 16px 36px #00000080;transform:translateY(-4px)}[data-theme=dark] .learn-section-advanced .lesson-neon-bar{background:linear-gradient(90deg, transparent, var(--route) 18%, var(--route-bright) 50%, var(--route) 82%, transparent);box-shadow:0 0 10px #3ecfff80}[data-theme=dark] .learn-section-advanced .lesson-link{background:linear-gradient(180deg, #3ecfff1a, transparent 42%), var(--surface);border-color:var(--route)}@supports (color:color-mix(in lab, red, red)){[data-theme=dark] .learn-section-advanced .lesson-link{border-color:color-mix(in srgb, var(--route) 65%, #0a0c12)}}[data-theme=dark] .learn-section-advanced .lesson-link{box-shadow:0 0 0 2px #0a0c12, 0 0 0 4px var(--route), 0 0 22px #3ecfff29, var(--shadow-soft)}@supports (color:color-mix(in lab, red, red)){[data-theme=dark] .learn-section-advanced .lesson-link{box-shadow:0 0 0 2px #0a0c12, 0 0 0 4px color-mix(in srgb, var(--route) 55%, #0a0c12), 0 0 22px #3ecfff29, var(--shadow-soft)}}[data-theme=dark] .learn-section-advanced .lesson-link:hover{box-shadow:0 0 0 2px #0a0c12, 0 0 0 4px var(--route-bright), var(--glow-cyan), 0 16px 36px #00000080}[data-theme=dark] .lesson-zh{color:var(--sign);text-shadow:0 0 10px #1fd98a47}[data-theme=dark] .learn-section-advanced .lesson-zh{color:var(--route);text-shadow:0 0 10px #3ecfff47}[data-theme=dark] .phrase-row,[data-theme=dark] .stat-chip,[data-theme=dark] .auth-panel,[data-theme=dark] .field,[data-theme=dark] .auth-field{background:linear-gradient(180deg, #ffffff05, transparent 40%), var(--surface);border-color:var(--sign)}@supports (color:color-mix(in lab, red, red)){[data-theme=dark] .phrase-row,[data-theme=dark] .stat-chip,[data-theme=dark] .auth-panel,[data-theme=dark] .field,[data-theme=dark] .auth-field{border-color:color-mix(in srgb, var(--sign) 30%, transparent)}}[data-theme=dark] .phrase-row,[data-theme=dark] .stat-chip,[data-theme=dark] .auth-panel,[data-theme=dark] .field,[data-theme=dark] .auth-field{box-shadow:0 0 0 1px #00000059}[data-theme=dark] .phrase-row:hover{border-color:var(--sign)}@supports (color:color-mix(in lab, red, red)){[data-theme=dark] .phrase-row:hover{border-color:color-mix(in srgb, var(--sign) 55%, transparent)}}[data-theme=dark] .phrase-row:hover{box-shadow:0 0 18px #1fd98a1f}[data-theme=dark] .phrase-zh{color:var(--ink);text-shadow:0 0 12px #1fd98a1f}[data-theme=dark] .flip-face{border-color:var(--sign);color:var(--ink);box-shadow:0 0 0 3px #05070c, 0 0 0 6px var(--sign), 0 0 34px #1fd98a47, var(--shadow);background:radial-gradient(80% 60% at 50% 35%,#1fd98a1a,#0000 60%),#10141e}@supports (color:color-mix(in lab, red, red)){[data-theme=dark] .flip-face{box-shadow:0 0 0 3px #05070c, 0 0 0 6px color-mix(in srgb, var(--sign) 55%, #05070c), 0 0 34px #1fd98a47, var(--shadow)}}[data-theme=dark] .flip-face.back{border-color:var(--neon-pink);box-shadow:0 0 0 3px #05070c, 0 0 0 6px var(--neon-pink), 0 0 34px #ff3d6e47, var(--shadow);background:radial-gradient(80% 60% at 50% 35%,#ff3d6e1a,#0000 60%),#140e16}@supports (color:color-mix(in lab, red, red)){[data-theme=dark] .flip-face.back{box-shadow:0 0 0 3px #05070c, 0 0 0 6px color-mix(in srgb, var(--neon-pink) 55%, #05070c), 0 0 34px #ff3d6e47, var(--shadow)}}[data-theme=dark] .flip-zh{color:var(--sign);text-shadow:0 0 12px #1fd98a8c,0 0 28px #1fd98a40}[data-theme=dark] .flip-face.back .flip-zh{color:var(--neon-pink);text-shadow:0 0 12px #ff3d6e80,0 0 24px #ff3d6e38}[data-theme=dark] .flip-face .jyutping,[data-theme=dark] .flip-face .phrase-en,[data-theme=dark] .flip-hint{color:#f7f1e8e0}[data-theme=dark] .field:focus,[data-theme=dark] .auth-field:focus{border-color:var(--neon-cyan);box-shadow:0 0 0 3px #3ecfff2e, var(--glow-cyan)}[data-theme=dark] .auth-plate{color:var(--sign);border-color:var(--sign);box-shadow:0 0 0 3px #05070c, 0 0 0 6px var(--neon-pink), var(--glow-sign);background:#07110c}@supports (color:color-mix(in lab, red, red)){[data-theme=dark] .auth-plate{box-shadow:0 0 0 3px #05070c, 0 0 0 6px color-mix(in srgb, var(--neon-pink) 50%, #05070c), var(--glow-sign)}}[data-theme=dark] .auth-tab.is-active{background:var(--sign);color:#06110c;box-shadow:0 0 14px #1fd98a59}[data-theme=dark] .tutor-panel{border-left:3px solid var(--neon-pink);box-shadow:-18px 0 50px #0000008c, var(--glow-pink);background:linear-gradient(#ff3d6e14,#0000 22%),#10141e}[data-theme=dark] .tutor-head{border-bottom-color:var(--neon-pink);background:linear-gradient(#ff3d6e24,#0000)}@supports (color:color-mix(in lab, red, red)){[data-theme=dark] .tutor-head{border-bottom-color:color-mix(in srgb, var(--neon-pink) 40%, transparent)}}[data-theme=dark] .tutor-title{color:var(--sign);text-shadow:0 0 12px #1fd98a4d}[data-theme=dark] .tutor-bubble.is-assistant{background:var(--surface-2);border-color:var(--neon-cyan)}@supports (color:color-mix(in lab, red, red)){[data-theme=dark] .tutor-bubble.is-assistant{border-color:color-mix(in srgb, var(--neon-cyan) 35%, transparent)}}[data-theme=dark] .tutor-bubble.is-user{border-color:var(--sign);background:#1fd98a1a}@supports (color:color-mix(in lab, red, red)){[data-theme=dark] .tutor-bubble.is-user{border-color:color-mix(in srgb, var(--sign) 45%, transparent)}}[data-theme=dark] .tutor-chip{border-color:var(--neon-pink)}@supports (color:color-mix(in lab, red, red)){[data-theme=dark] .tutor-chip{border-color:color-mix(in srgb, var(--neon-pink) 40%, transparent)}}[data-theme=dark] .tutor-chip{color:var(--neon-pink);background:#ff3d6e0f}[data-theme=dark] .tutor-chip:hover:not(:disabled){border-color:var(--neon-pink);box-shadow:var(--glow-pink);background:#ff3d6e24}[data-theme=dark] .btn-icon-slow{color:var(--amber);border-color:var(--amber);background:#ffb7031f}@supports (color:color-mix(in lab, red, red)){[data-theme=dark] .btn-icon-slow{border-color:color-mix(in srgb, var(--amber) 45%, transparent)}}[data-theme=dark] .btn-icon-slow{box-shadow:0 0 12px #ffb70326}[data-theme=dark] .btn-icon-ai{color:var(--neon-pink);border-color:var(--neon-pink)}@supports (color:color-mix(in lab, red, red)){[data-theme=dark] .btn-icon-ai{border-color:color-mix(in srgb, var(--neon-pink) 45%, transparent)}}[data-theme=dark] .btn-icon-ai{box-shadow:none}[data-theme=dark] .btn-icon-ai:hover{box-shadow:var(--glow-pink);background:#ff3d6e1a}[data-theme=dark] .btn-srs.again{border-color:var(--neon-pink);color:var(--neon-pink);box-shadow:0 0 12px #ff3d6e26}[data-theme=dark] .btn-srs.good,[data-theme=dark] .btn-srs.easy{border-color:var(--sign);color:var(--sign);box-shadow:0 0 12px #1fd98a26}@keyframes neon-tube-pulse{0%,to{opacity:.82;filter:brightness(.95)}50%{opacity:1;filter:brightness(1.12)}}@keyframes neon-flicker{0%,19%,21%,23%,25%,54%,56%,to{opacity:1}20%,24%,55%{opacity:.45}}@keyframes neon-rain{0%{background-position:0 0}to{background-position:24px 96px}}@keyframes neon-wash{0%{opacity:.85;transform:scale(1)}to{opacity:1;transform:scale(1.03)}}@media 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