@import"https://fonts.googleapis.com/css2?family=Google+Sans+Flex:wght@300..700&family=Material+Symbols+Rounded:opsz,wght,FILL,GRAD@24,500,0,0&display=swap";:root{color-scheme:light;--color-app-bg: #fbfbfd;--color-text: #1f1f1f;--color-text-soft: #3c4043;--color-muted: #5f6368;--color-surface: #ffffff;--color-panel: rgba(255, 255, 255, .92);--color-footer-bg: rgba(255, 255, 255, .74);--color-border: #dadce0;--color-border-soft: #eceff3;--color-hover-border: #c7ccd4;--color-hover-bg: #f8fafd;--color-primary-bg: #111111;--color-primary-bg-hover: #000000;--color-primary-fg: #ffffff;--color-accent: #1a73e8;--color-accent-hover: #155fc4;--color-error: #b3261e;--color-error-bg: rgba(179, 38, 30, .07);--color-success: #137333;--color-streak-bg: #ebe9e5;--color-streak-icon: #96928a;--color-streak-text: #8d8981;--shadow-panel: 0 18px 54px rgba(60, 64, 67, .1);--shadow-menu: 0 16px 44px rgba(60, 64, 67, .14);--focus-ring: rgba(26, 115, 232, .14);--backdrop-bg: rgba(248, 250, 253, .72);--skeleton-base: #e6e9ee;--skeleton-sheen: rgba(255, 255, 255, .72);--ambient-core: radial-gradient( ellipse at 50% 50%, rgba(102, 132, 255, .46) 0%, rgba(66, 154, 238, .26) 28%, rgba(171, 95, 255, .16) 50%, transparent 74% );--ambient-spectrum: conic-gradient( from 220deg at 50% 52%, rgba(81, 126, 255, .28), rgba(39, 214, 198, .2), rgba(184, 92, 255, .24), rgba(255, 121, 171, .18), rgba(123, 211, 99, .16), rgba(81, 126, 255, .28) );--ambient-sheen: radial-gradient( ellipse at 44% 40%, rgba(255, 255, 255, .38), rgba(255, 255, 255, .08) 36%, transparent 66% );--ambient-opacity: .7;font-family:Google Sans Flex,Google Sans,Arial,ui-sans-serif,system-ui,-apple-system,BlinkMacSystemFont,Segoe UI,sans-serif;background:var(--color-app-bg);color:var(--color-text);font-synthesis:none;text-rendering:optimizeLegibility;-webkit-font-smoothing:antialiased}:root[data-theme=dark]{color-scheme:dark;--color-app-bg: #111315;--color-text: #f1f3f4;--color-text-soft: #d7dade;--color-muted: #a8adb4;--color-surface: #1b1d20;--color-panel: rgba(30, 32, 36, .94);--color-footer-bg: rgba(17, 19, 21, .86);--color-border: #3b4048;--color-border-soft: #2c3138;--color-hover-border: #555c66;--color-hover-bg: #24282f;--color-primary-bg: #f8fafc;--color-primary-bg-hover: #ffffff;--color-primary-fg: #111315;--color-accent: #8ab4f8;--color-accent-hover: #aecbfa;--color-error: #f2b8b5;--color-error-bg: rgba(242, 184, 181, .11);--color-success: #81c995;--color-streak-bg: #2d2d2b;--color-streak-icon: #bbb7ae;--color-streak-text: #bbb7ae;--shadow-panel: 0 18px 54px rgba(0, 0, 0, .32);--shadow-menu: 0 18px 48px rgba(0, 0, 0, .36);--focus-ring: rgba(138, 180, 248, .22);--backdrop-bg: rgba(17, 19, 21, .72);--skeleton-base: #2c3138;--skeleton-sheen: rgba(255, 255, 255, .12);--ambient-core: radial-gradient( ellipse at 50% 50%, rgba(61, 83, 223, .74) 0%, rgba(33, 88, 203, .48) 30%, rgba(78, 47, 162, .22) 53%, transparent 76% );--ambient-spectrum: conic-gradient( from 220deg at 50% 52%, rgba(75, 113, 255, .42), rgba(22, 211, 207, .22), rgba(151, 79, 255, .34), rgba(255, 92, 158, .2), rgba(91, 218, 147, .18), rgba(75, 113, 255, .42) );--ambient-sheen: radial-gradient( ellipse at 44% 39%, rgba(186, 210, 255, .14), rgba(118, 89, 255, .08) 38%, transparent 68% );--ambient-opacity: .86}*{box-sizing:border-box}body{margin:0;min-width:320px;min-height:100vh;background:var(--color-app-bg);color:var(--color-text)}button,input,select,textarea{font:inherit}button{border:0}a{color:inherit;text-decoration:none}h1,h2,h3,p{margin-top:0}h1{margin-bottom:0;font-size:2.45rem;font-weight:500;letter-spacing:0;line-height:1.08}h2{margin-bottom:10px;font-size:1rem;font-weight:520;letter-spacing:0}p{color:var(--color-muted);line-height:1.55}.fluento-shell,.lesson-shell{display:flex;flex-direction:column;min-height:100vh;background:var(--color-app-bg)}.minimal-header{position:relative;z-index:4;display:grid;grid-template-columns:minmax(0,1fr) auto minmax(0,1fr);width:min(1180px,calc(100% - 32px));min-height:76px;align-items:center;gap:18px;margin:0 auto;padding:14px 0}.brand-mark{display:inline-flex;flex:0 0 auto;justify-self:start;align-items:center;color:var(--color-text);font-size:1.05rem;font-weight:520}.brand-mark img{display:block;width:118px;height:auto;transition:filter .16s ease}:root[data-theme=dark] .brand-mark img{filter:invert(1)}.header-actions,.user-cluster,.auth-controls,.action-row,.submit-row,.dialog-actions,.course-card-actions{display:flex;align-items:center;gap:10px}.header-actions{grid-column:3;justify-self:end;justify-content:flex-end;gap:22px}.streak-badge{display:inline-flex;width:116px;min-height:50px;grid-column:2;justify-self:center;align-items:center;justify-content:center;gap:13px;padding:0 18px;border-radius:999px;background:var(--color-streak-bg);color:var(--color-streak-text);line-height:1;white-space:nowrap}.streak-badge strong{color:var(--color-streak-text);font-size:1.55rem;font-weight:700}.streak-badge-icon{display:block;width:30px;height:30px;flex:0 0 auto;background:var(--color-streak-icon);mask:var(--streak-fire-icon) center / contain no-repeat;-webkit-mask:var(--streak-fire-icon) center / contain no-repeat}.streak-badge-placeholder{visibility:hidden}.user-cluster{min-width:0;color:var(--color-muted);font-size:.92rem}.auth-controls{min-height:44px}.user-cluster>span{max-width:220px;overflow:hidden;text-overflow:ellipsis;white-space:nowrap}.auth-status{color:var(--color-muted);font-size:.92rem}.button{display:inline-flex;min-height:40px;align-items:center;justify-content:center;gap:8px;padding:0 16px;border-radius:999px;cursor:pointer;font-weight:520;letter-spacing:0;transition:transform .16s ease,background-color .16s ease,border-color .16s ease,color .16s ease,opacity .16s ease}.material-symbol{display:inline-flex;align-items:center;font-family:Material Symbols Rounded;font-size:1.25em;font-style:normal;font-weight:500;line-height:1}.button:hover{transform:translateY(-1px)}.button:disabled{cursor:not-allowed;opacity:.58;transform:none}.button-spinner{display:inline-block;width:16px;height:16px;flex:0 0 auto;border:2px solid currentColor;border-right-color:transparent;border-radius:50%;animation:button-spinner-rotate .72s linear infinite}@keyframes button-spinner-rotate{to{transform:rotate(360deg)}}.button-primary{background:var(--color-primary-bg);color:var(--color-primary-fg)}.button-primary:hover{background:var(--color-primary-bg-hover)}.button.create-course-button{width:50px;min-width:50px;height:50px;min-height:50px;flex:0 0 50px;padding:0;font-size:1.65rem;line-height:1}.button-blue{background:var(--color-accent);color:var(--color-primary-fg)}.button-blue:hover{background:var(--color-accent-hover)}.button-secondary{border:1px solid var(--color-border);background:var(--color-surface);color:var(--color-text)}.button-secondary:hover{border-color:var(--color-hover-border);background:var(--color-hover-bg)}.button-ghost{background:transparent;color:var(--color-muted)}.button-large{min-height:48px;padding:0 22px}.empty-course-state,.course-create-state,.auth-required-state,.course-home{position:relative;display:grid;flex:1;min-height:0;place-items:center;padding:32px 16px 80px}.empty-course-state,.course-create-state,.auth-required-state{overflow:hidden}.ambient-gradient{position:fixed;z-index:0;top:50%;left:50%;width:min(1240px,108vw);height:min(680px,74vh);border-radius:999px;opacity:0;pointer-events:none;transform:translate3d(-50%,-50%,0);animation:ambient-appear .9s cubic-bezier(.16,1,.3,1) .12s forwards;will-change:opacity}.ambient-gradient:before,.ambient-gradient:after{position:absolute;border-radius:inherit;content:""}.ambient-gradient:before{inset:0;background:var(--ambient-core),var(--ambient-spectrum);filter:blur(42px) saturate(1.18);transform:scale(.98);animation:ambient-breathe 12s ease-in-out .9s infinite alternate}.ambient-gradient:after{inset:6% 8%;background:var(--ambient-sheen),var(--ambient-spectrum);filter:blur(66px) saturate(1.24);opacity:.56;transform:rotate(-5deg) scale(.92);animation:ambient-shift 16s ease-in-out .9s infinite alternate}.ambient-gradient.compact{width:min(1180px,108vw);height:min(640px,72vh)}@keyframes ambient-appear{0%{opacity:0;filter:blur(10px)}to{opacity:var(--ambient-opacity);filter:blur(0)}}@keyframes ambient-breathe{0%{transform:translate3d(-16px,8px,0) scale(.98)}to{transform:translate3d(18px,-10px,0) scale(1.05)}}@keyframes ambient-shift{0%{transform:rotate(-7deg) translate3d(22px,-8px,0) scale(.92)}to{transform:rotate(8deg) translate3d(-20px,12px,0) scale(1.03)}}.empty-course-content{position:relative;z-index:1;display:grid;justify-items:center;gap:28px;text-align:center}.course-list{position:relative;z-index:1;display:grid;width:min(720px,100%);gap:18px}.course-card,.auth-required-panel,.lesson-brief-panel,.handoff-panel,.lesson-focus-panel,.submit-panel,.lesson-feedback-banner{border:0;border-radius:28px;background:var(--color-panel);box-shadow:var(--shadow-panel)}.course-card{position:relative;z-index:1;display:grid;width:min(720px,100%);gap:28px;padding:28px}.auth-required-panel{position:relative;z-index:1;display:grid;width:min(560px,100%);justify-items:center;gap:18px;padding:32px;text-align:center}.auth-required-panel h1{font-size:2rem}.auth-required-panel p{max-width:420px;margin-bottom:0}.sr-only{position:absolute;width:1px;height:1px;overflow:hidden;clip:rect(0,0,0,0);clip-path:inset(50%);white-space:nowrap}.course-card-main{display:grid;gap:10px}.course-card-top{display:flex;align-items:center;justify-content:space-between;gap:16px}.course-language-route{display:inline-flex;width:max-content;align-items:center;gap:8px}.course-language-flag{display:inline-flex;width:30px;height:30px;flex:0 0 auto;align-items:center;justify-content:center;overflow:hidden;border:1px solid var(--color-border);border-radius:50%;background:var(--color-surface);box-shadow:0 2px 8px #3c404314}.course-language-flag img{display:block;width:100%;height:100%;object-fit:cover}.course-language-flag-fallback{color:var(--color-muted)}.course-language-flag-fallback .material-symbol{font-size:1.08rem}.course-language-arrow{color:var(--color-muted);font-size:1.04rem}.course-card-controls{display:inline-flex;flex:0 0 auto;align-items:center;gap:8px}.icon-button{display:inline-flex;width:40px;height:40px;align-items:center;justify-content:center;border:1px solid var(--color-border);border-radius:50%;background:var(--color-surface);color:var(--color-muted);cursor:pointer;transition:background-color .16s ease,border-color .16s ease,color .16s ease,transform .16s ease}.icon-button .material-symbol{font-size:1.2rem}.icon-button:hover{border-color:var(--color-hover-border);background:var(--color-hover-bg);color:var(--color-text);transform:translateY(-1px)}.icon-button-danger:hover{border-color:#b3261e2e;background:var(--color-error-bg);color:var(--color-error)}.course-card-main p{max-width:560px;margin-bottom:0}.muted-line{color:var(--color-muted);font-size:.9rem;line-height:1.35}.course-metrics{display:grid;grid-template-columns:repeat(4,minmax(0,1fr));gap:1px;overflow:hidden;border:1px solid var(--color-border-soft);border-radius:18px;background:var(--color-border-soft)}.metric-item{display:grid;min-height:72px;align-content:center;gap:5px;padding:12px;background:var(--color-surface)}.metric-item span{color:var(--color-muted);font-size:.82rem}.metric-item strong{color:var(--color-text);font-size:1.18rem;font-weight:560}.course-card-actions{justify-content:space-between}.course-loading-card{pointer-events:none}.skeleton-route{display:inline-flex;align-items:center;gap:8px}.skeleton-line,.skeleton-circle,.skeleton-button{display:block;overflow:hidden;background:linear-gradient(90deg,transparent,var(--skeleton-sheen),transparent),var(--skeleton-base);background-size:220% 100%,100% 100%;animation:skeleton-shimmer 1.35s ease-in-out infinite}.skeleton-line{height:14px;border-radius:999px}.skeleton-circle{width:30px;height:30px;flex:0 0 auto;border-radius:50%}.skeleton-control{width:40px;height:40px}.skeleton-line-icon{width:18px;height:12px}.skeleton-title{width:min(360px,82%);height:42px;border-radius:12px}.skeleton-copy{width:min(430px,76%)}.skeleton-metric{background:var(--color-surface)}.skeleton-label{width:72%;height:11px}.skeleton-value{width:42%;height:20px}.skeleton-button{width:124px;height:40px;flex:0 0 auto;border-radius:999px}@keyframes skeleton-shimmer{0%{background-position:180% 0,0 0}to{background-position:-80% 0,0 0}}.modal-backdrop{position:fixed;z-index:10;inset:0;display:grid;place-items:center;overflow-y:auto;padding:24px 16px;background:var(--backdrop-bg);-webkit-backdrop-filter:blur(12px);backdrop-filter:blur(12px)}.dialog-actions{justify-content:space-between}.course-form .dialog-actions{justify-content:flex-end}.form-grid,.skill-grid{display:grid;gap:12px}.two-columns{grid-template-columns:repeat(2,minmax(0,1fr))}.skill-grid{grid-template-columns:repeat(5,minmax(96px,1fr))}.field-control{display:grid;gap:7px}.field-control span{color:var(--color-muted);font-size:.86rem}.field-control input,.field-control select,.field-control textarea{width:100%;min-height:44px;border:1px solid var(--color-border);border-radius:8px;outline:none;background:var(--color-surface);color:var(--color-text);padding:0 12px}.field-control textarea{min-height:92px;padding:12px;resize:vertical;line-height:1.45}.field-control input:focus,.field-control select:focus,.field-control textarea:focus{border-color:var(--color-accent);box-shadow:0 0 0 3px var(--focus-ring)}.compact-field select{min-height:40px}.lesson-shell{overflow-x:hidden}.lesson-home{position:relative;display:grid;flex:1;min-height:0;justify-items:center;align-content:stretch;padding:32px 16px 80px}.lesson-page-content{position:relative;z-index:1;display:flex;min-height:0;flex-direction:column;width:min(1180px,100%);gap:18px}.lesson-page-heading{display:flex;align-items:center;gap:16px}.lesson-back-button{flex:0 0 auto}.lesson-title-block{display:grid;min-width:0;flex:1;gap:4px}.lesson-title-block h1{overflow-wrap:anywhere}.lesson-title-prefix{font-weight:300}.lesson-grid{display:grid;width:100%;align-items:start;grid-template-columns:minmax(250px,330px) minmax(0,1fr);gap:18px}.lesson-brief-panel,.handoff-panel,.lesson-focus-panel,.submit-panel,.lesson-feedback-banner{padding:28px}.lesson-brief-panel{display:grid;align-self:stretch;align-content:start}.lesson-brief-panel p{margin-bottom:18px}.lesson-meta{display:flex;flex-wrap:wrap;gap:8px;margin-bottom:20px}.lesson-meta>span{border:1px solid var(--color-border);border-radius:999px;padding:6px 10px;color:var(--color-muted);font-size:.84rem}.profile-summary,.chunk-list{display:flex;flex-wrap:wrap;gap:7px}.profile-summary{margin-bottom:18px}.profile-summary span,.chunk-list span{border:1px solid var(--color-border-soft);border-radius:999px;background:var(--color-surface);color:var(--color-text-soft);font-size:.84rem;line-height:1.25;padding:7px 10px}.lesson-workspace{display:grid;gap:16px}.handoff-panel{display:flex;align-items:center;justify-content:space-between;gap:14px}.handoff-panel h2,.lesson-focus-panel h2,.submit-panel h2{margin-bottom:4px}.lesson-focus-panel{display:grid;gap:20px}.sentence-list{display:grid;gap:8px;margin:0;padding-left:20px;color:var(--color-text-soft);line-height:1.5}.report-box{min-height:220px}.submit-row{justify-content:space-between;margin-top:12px}.status-message{min-height:24px;margin:0;color:var(--color-muted)}.status-error{color:var(--color-error)}.status-saved{color:var(--color-success)}.lesson-feedback-banner{display:grid;grid-template-columns:minmax(0,1fr) auto;align-items:center;gap:24px}.lesson-feedback-copy{min-width:0}.lesson-feedback-copy h2{margin-bottom:10px}.lesson-feedback-copy p{margin-bottom:0;color:var(--color-text-soft)}.lesson-score-summary{display:grid;min-width:128px;justify-items:end;gap:12px}.lesson-score-summary>span{color:var(--color-text);font-size:clamp(2.2rem,5vw,3.8rem);font-weight:560;letter-spacing:0;line-height:1;white-space:nowrap}.lesson-equalizer{position:fixed;z-index:3;top:50%;right:clamp(16px,3vw,42px);width:34px;transform:translateY(-50%);pointer-events:none}.lesson-equalizer-bars{display:grid;justify-items:end;gap:7px;max-height:min(62vh,520px);overflow:hidden}.lesson-equalizer-item{display:flex;width:100%;min-height:10px;align-items:center;justify-content:flex-end;pointer-events:auto}.lesson-equalizer-bar{display:block;width:28px;height:3px;min-height:3px;max-height:3px;border:0;border-radius:999px;background:var(--color-primary-bg);opacity:.92;padding:0;transition:background-color .16s ease,opacity .16s ease,transform .16s ease}button.lesson-equalizer-bar{cursor:pointer}button.lesson-equalizer-bar:focus-visible{outline:2px solid var(--focus-ring);outline-offset:5px}.lesson-equalizer-item:hover .lesson-equalizer-bar,.lesson-equalizer-item:focus-within .lesson-equalizer-bar,.lesson-equalizer-item.is-current .lesson-equalizer-bar{background:var(--color-accent);opacity:1;transform:translate(-2px)}.app-footer{position:relative;z-index:5;flex:0 0 auto;background:var(--color-footer-bg);-webkit-backdrop-filter:blur(14px);backdrop-filter:blur(14px)}.app-footer-inner{display:flex;width:min(1180px,calc(100% - 32px));min-height:72px;align-items:center;justify-content:space-between;gap:18px;margin:0 auto;padding:14px 0}.footer-copy{display:flex;min-width:0;flex-wrap:wrap;align-items:center;gap:7px 14px;color:var(--color-muted);font-size:.84rem;line-height:1.35}.footer-copy strong{color:var(--color-text);font-weight:560}.theme-switcher{position:relative;flex:0 0 auto}.theme-trigger{display:inline-flex;width:28px;height:28px;align-items:center;justify-content:center;padding:0;background:transparent;color:var(--color-muted);cursor:pointer;transition:color .16s ease,transform .16s ease}.theme-trigger:hover{color:var(--color-text);transform:translateY(-1px)}.theme-trigger:focus-visible{border-radius:6px;outline:2px solid var(--focus-ring);outline-offset:3px}.theme-trigger .material-symbol{font-size:1.35rem}.theme-menu{position:absolute;right:0;bottom:calc(100% + 10px);display:grid;width:176px;gap:2px;padding:6px;border:1px solid var(--color-border);border-radius:8px;background:var(--color-surface);box-shadow:var(--shadow-menu)}.theme-menu-item{display:grid;width:100%;min-height:38px;grid-template-columns:22px minmax(0,1fr) 20px;align-items:center;gap:8px;padding:0 8px;border-radius:6px;background:transparent;color:var(--color-muted);cursor:pointer;text-align:left}.theme-menu-item:hover,.theme-menu-item.is-active{background:var(--color-hover-bg);color:var(--color-text)}.theme-menu-check,.theme-menu-check-placeholder{justify-self:end}.theme-menu-check{color:var(--color-accent);font-size:1rem}@media(max-width:900px){h1{font-size:2rem}.minimal-header,.header-actions,.course-card-actions,.handoff-panel,.submit-row,.lesson-feedback-banner{align-items:stretch;flex-direction:column}.lesson-feedback-banner{display:flex}.lesson-score-summary{justify-items:start}.minimal-header{display:flex;gap:12px}.header-actions,.auth-controls,.action-row,.streak-badge{width:100%}.brand-mark,.header-actions,.streak-badge{justify-self:stretch}.user-cluster{justify-content:space-between}.button{width:100%}.course-metrics,.two-columns,.skill-grid,.lesson-grid{grid-template-columns:1fr}.lesson-brief-panel{align-self:start}.empty-course-state,.course-create-state,.course-home,.lesson-home{min-height:auto;padding-top:80px}.lesson-page-content{min-height:0}.lesson-page-heading{align-items:flex-start}.lesson-equalizer{right:12px;width:auto}.lesson-equalizer-bars{gap:5px;max-height:50vh}.lesson-equalizer-bar{width:24px}.ambient-gradient{width:132vw;height:min(560px,66vh)}.app-footer-inner{align-items:stretch;flex-direction:column}.footer-copy{justify-content:center;text-align:center}.theme-switcher{align-self:center}.theme-menu{right:50%;transform:translate(50%)}}