:root{color-scheme:dark;--page:#101315;--surface:#191e21;--raised:#22292d;--line:#343d42;--ink:#e6ecef;--muted:#afbbc2;--accent:#70d5ad;--amber:#e8ba77;font-family:"Microsoft YaHei","PingFang SC",Arial,sans-serif;font-size:15px}*{box-sizing:border-box}body{margin:0;background:var(--page);color:var(--ink);line-height:1.7}button,input,select,textarea{font:inherit}button,select{cursor:pointer}button{min-height:42px;padding:8px 17px;border:1px solid var(--line);border-radius:24px;background:var(--raised);color:var(--ink);transition:background .15s,border-color .15s}button:hover{background:#303b41;border-color:#61736d}button:disabled{cursor:not-allowed;background:#1c2327;color:#839198;border-color:#343e43}button:focus-visible,input:focus-visible,textarea:focus-visible,select:focus-visible{outline:2px solid #91e6c5;outline-offset:3px}button.primary,button.active,button[aria-pressed=true]{background:var(--accent);border-color:var(--accent);color:#0d2b20}.quiet{background:transparent}.mini{font-size:12px;min-height:34px;padding:5px 12px}.muted,.fine{color:var(--muted)}.fine{font-size:12px;line-height:1.8}.overline{color:var(--accent);font:11px/1.5 Arial,sans-serif;letter-spacing:2px}.panel{background:var(--surface);border:1px solid var(--line);border-radius:15px;padding:22px}.panel h2{font-size:21px;margin:0 0 9px;font-weight:500}.panel h3{font-size:16px;margin:8px 0}.panel p{margin:7px 0}h1,h2,h3{font-weight:500}button,a,input,textarea{-webkit-tap-highlight-color:transparent}a{color:#9de9cd}input[type=range]{accent-color:var(--accent);width:100%;min-height:30px}input[type=number],input[type=text],textarea,select{background:#111619;border:1px solid #46515a;border-radius:8px;padding:8px 11px;color:var(--ink);max-width:100%}input[type=checkbox]{accent-color:var(--accent);width:17px;height:17px}textarea{width:100%;resize:vertical}.site-header{padding:19px 4vw;display:flex;justify-content:space-between;align-items:center;border-bottom:1px solid #293036;background:#14191c;gap:18px}.site-header nav,.inline{display:flex;align-items:center;gap:9px;flex-wrap:wrap}.brand{display:flex;align-items:center;text-align:left;gap:12px;border:0;background:none;padding:0;border-radius:5px}.brand:hover{background:none}.brand strong{font-weight:500;display:block;font-size:17px}.brand small{font-size:12px;color:var(--muted);display:block}#app{max-width:1580px;width:92%;margin:0 auto;min-height:calc(100vh - 205px)}.home-hero{margin:32px 0 35px;border-radius:20px;min-height:345px;background-position:right center;background-size:cover;position:relative;padding:48px;display:flex;align-items:center;overflow:hidden}.home-hero:before{content:"";position:absolute;inset:0;background:linear-gradient(90deg,#11191cf5 0%,#11191cdd 37%,#11191c22 100%)}.home-hero>div{position:relative;max-width:600px}.home-hero h1{font-size:clamp(34px,4vw,58px);line-height:1.3;margin:16px 0}.home-hero p{color:#c0cec8;font-size:16px;max-width:470px}.home-hero button{margin-top:16px}.section-label{display:flex;justify-content:space-between;align-items:center;margin:20px 0;color:var(--muted);gap:15px}.section-label strong{font-size:19px;color:var(--ink);font-weight:500}.module-grid{display:grid;grid-template-columns:repeat(3,1fr);gap:20px}.module-card{position:relative;padding:0;border:1px solid var(--line);border-radius:16px;background:var(--surface);text-align:left;overflow:hidden;display:flex;flex-direction:column;min-height:365px}.module-card:hover{border-color:#78988c;background:#20292a}.module-card img{width:100%;height:170px;object-fit:cover;display:block;background:#141b19}.module-card .copy{padding:22px;flex:1}.module-card h2{font-size:25px;line-height:1.5;margin:10px 0}.module-card p{color:var(--muted);font-size:14px;margin:0}.module-card .card-bottom{display:flex;justify-content:space-between;align-items:center;border-top:1px solid #343d42;margin-top:23px;padding-top:14px;color:var(--accent);font-size:13px}.home-note{margin:25px 0 40px;padding:18px 0;border-bottom:1px solid var(--line);color:var(--muted);font-size:13px}.workspace-heading{display:flex;justify-content:space-between;align-items:center;gap:20px;margin:28px 0 18px}.workspace-heading h1{margin:5px 0;font-size:29px}.workspace-heading p{margin:0;color:var(--muted);font-size:14px}.section-switch{display:flex;gap:8px;margin-bottom:20px;flex-wrap:wrap}.section-switch button{font-size:13px}.site-footer{max-width:1450px;width:92%;margin:35px auto 0;padding:22px 0;display:flex;justify-content:space-between;color:#81918f;border-top:1px solid #2b363b;font-size:12px}dialog{max-width:950px;width:90vw;max-height:87vh;border:1px solid #52615e;border-radius:18px;padding:25px;background:#1a2124;color:var(--ink)}dialog::backdrop{background:#000b}dialog>header{display:flex;justify-content:space-between;align-items:center;gap:20px;margin-bottom:17px}dialog h2{margin:0;font-size:23px}dialog header button{font-size:24px;min-width:40px;padding:0}.note-grid{display:grid;grid-template-columns:1fr 1fr;gap:15px}.note-grid section{padding:16px;border:1px solid var(--line);border-radius:10px}.note-grid h3{margin:0;font-size:17px}.note-grid p{color:var(--muted);font-size:14px}.record-list{margin:20px 0}.record-list article{padding:14px 0;border-bottom:1px solid var(--line)}.record-list article p{color:var(--muted);font-size:13px;margin:4px 0}#toast{position:fixed;bottom:25px;left:50%;transform:translate(-50%,15px);padding:12px 22px;border:1px solid #679987;background:#20362f;border-radius:12px;color:#def1e9;max-width:90vw;z-index:100;opacity:0;pointer-events:none;transition:.2s}#toast.show{opacity:1;transform:translate(-50%,0)}[hidden]{display:none!important}table{width:100%;border-collapse:collapse;font-size:13px}th,td{text-align:left;padding:10px;border-bottom:1px solid #344149}th{color:var(--muted);font-weight:400}.table-scroll{overflow:auto}.empty{color:var(--muted);padding:24px;text-align:center}.error{border-color:#ac7f69!important;color:#ffd4b4}.success{color:var(--accent)}
@media(max-width:950px){.home-hero{padding:30px;min-height:300px}.module-card h2{font-size:22px}.module-card .copy{padding:16px}.site-header{padding:15px 4%}.brand strong{font-size:15px}.site-header nav button{font-size:12px;padding:6px 12px}.module-card img{height:135px}.note-grid{grid-template-columns:1fr}}@media(max-width:650px){:root{font-size:14px}#app{width:94%}.site-header{gap:7px}.brand{gap:8px}.brand small{font-size:10px}.brand strong{font-size:13px}.site-header nav{gap:4px}.site-header nav button{padding:5px 9px;min-height:34px}.home-hero{padding:24px;min-height:290px;margin:18px 0}.home-hero h1{font-size:37px}.home-hero p{font-size:14px}.module-grid{grid-template-columns:1fr}.module-card{min-height:0}.module-card img{height:150px}.module-card h2{font-size:24px}.module-card .copy{padding:20px}.workspace-heading{align-items:flex-start}.workspace-heading h1{font-size:23px}.workspace-heading>button{font-size:12px;padding:5px 12px;white-space:nowrap}.panel{padding:16px}.site-footer{gap:12px;font-size:10px}.section-label{align-items:flex-start;flex-direction:column}dialog{width:95vw;padding:18px}.section-switch button{font-size:12px;padding:6px 12px}}

/* V06 shell: module navigation remains on the directory page only. */
.workspace-actions{display:flex;gap:10px;flex-wrap:wrap;align-items:center;justify-content:flex-end}
.workspace-actions [data-action="restart"]{border:1px solid #4c675e;color:#b9deca;background:#202d28}
@media(max-width:680px){.workspace-actions{justify-content:flex-start;width:100%}.workspace-actions button{min-height:44px;flex:1}.workspace-heading{align-items:flex-start}}

/* Mathematical typography: variables italic, descriptive indices upright. */
var,.math-var{font-family:"Times New Roman",serif;font-style:italic}sub,sup{font-style:normal}sub var,sub .math-var{font-style:italic}.math-roman{font-style:normal}.math-formula{font-family:"Times New Roman",serif;line-height:1.7;font-variant-numeric:lining-nums}

/* A narrow operation window reserves an upper strip for its principle HUD. */
.principles .pr-bench-panel{container-type:inline-size;container-name:optical-principle}
@container optical-principle (max-width:680px){
 .principles:not([data-principle=lcd]) .pr-viewport{padding-top:260px;background:linear-gradient(160deg,#0c1923,#14231f)}
 .principles:not([data-principle=lcd]) .pr-viewport:has(.pr-principle-hud.folded){padding-top:54px}
 .principles[data-principle] .pr-operation .pr-scene{height:360px;height:min(360px,90cqw)}
 .principles[data-principle] .pr-operation .pr-principle-hud{max-height:248px;overflow:auto}
 .principles[data-principle] .pr-operation .pr-principle-hud .pr-hud-head{position:sticky;top:0;background:#0a202c;z-index:1}
}
@media(max-width:600px){
 .principles:not([data-principle=lcd]) .pr-viewport{padding-top:260px;background:linear-gradient(160deg,#0c1923,#14231f)}
 .principles:not([data-principle=lcd]) .pr-viewport:has(.pr-principle-hud.folded){padding-top:54px}
 .principles[data-principle] .pr-operation .pr-scene{height:360px;height:min(360px,90cqw)}
 .principles[data-principle] .pr-operation .pr-principle-hud{max-height:248px;overflow:auto}
 .principles[data-principle] .pr-operation .pr-principle-hud .pr-hud-head{position:sticky;top:0;background:#0a202c;z-index:1}
}

/* V15.2 explicit whole-course restart, secondary to the wallet balance. */
.wallet-restart-all{margin-top:26px;padding-top:20px;border-top:1px solid var(--line,#344044);display:grid;gap:12px}.wallet-restart-all strong{font-size:15px}.wallet-restart-all p{margin:7px 0 0;line-height:1.6}.wallet-restart-all button{justify-self:start;color:#e7c4ae;border-color:#665047;white-space:normal;text-align:left}#resetAllFeedback{min-height:1.5em;line-height:1.6}#dialog button[hidden]{display:none!important}

.wallet-passphrase{margin:20px 0 26px;padding:18px;border:1px solid #35483f;border-radius:12px;background:#122018}.wallet-passphrase>label{display:block;font-size:14px;color:#d9e9df;margin-bottom:10px}.wallet-passphrase .inline{align-items:stretch;flex-wrap:wrap}.wallet-passphrase .passphrase-input{flex:1;min-width:130px;width:auto;margin:0}.wallet-passphrase .passphrase-feedback{margin-bottom:0;min-height:20px}.wallet-passphrase button[hidden]{display:none}

/* The school identity is text so its full college name stays legible on mobile. */
.site-header .brand{min-width:0;flex:1 1 auto;max-width:100%}.site-header .brand>span{min-width:0}.site-header .brand small{white-space:normal;overflow-wrap:anywhere;line-height:1.65;margin-top:3px}.site-header nav{flex:0 1 auto;justify-content:flex-end}
@media(max-width:540px){.site-header{flex-wrap:wrap;align-items:flex-start;row-gap:12px}.site-header .brand{flex-basis:100%}.site-header nav{width:100%;justify-content:flex-start}.site-header .brand small{font-size:11px}}

/* V08 uses the verified introduction course's dark theme and prompt palette. */
:root{--page:#101315;--surface:#191e21;--raised:#22292d;--line:#343d42;--muted:#afbbc2;--accent:#70d5ad;--ink:#e6ecef}
body{scrollbar-color:#52616a #151a1d}::selection{background:#316753;color:#fff}
.principles .pr-bench-panel,.principles .pr-card,.principles .pr-mechanism{background:#191e21;border-color:#343d42;border-radius:12px}
.principles .pr-bench-head,.principles .pr-lcd-readout{background:#182328;color:#e0edf1;border-color:#34464b}
.principles .pr-tabs button{background:#22292d;border-color:#46525a;color:#e6ecef;border-radius:12px}
.principles .pr-tabs button.active{background:#70d5ad;border-color:#70d5ad;color:#0d2b20}
.principles .pr-tabs button.active span{color:#215e47}
.principles .pr-principle-hud{background:rgba(23,30,34,.97);border:1px solid #46575e;border-radius:12px;box-shadow:0 6px 24px #0006;backdrop-filter:blur(8px)}
.principles .pr-principle-hud::before{display:none}
.principles .pr-hud-head,.principles[data-principle] .pr-operation .pr-principle-hud .pr-hud-head{background:#232f34;border-color:#3e5057}
.principles .pr-hud-head strong{color:#e7f5f3;letter-spacing:.03em}
.principles .pr-hud-head button{background:#222f31;border-color:#4f6660;color:#c4d8d1;border-radius:6px}
.principles .pr-hud-head button:hover{background:#374b43;border-color:#729d8a}
.principles .pr-hud-body .pr-canvas-caption{color:#a7bcb0}
.principles .pr-lcd-readout b{color:#a9e8c7}
.principles .pr-rgb-presets button.active{border-color:#70d5ad;background:#203b30;color:#d9f6e6}
.principles .pr-lcd-pixel{border-radius:8px;border-color:#46575e}
.principles .pr-inventory-head{border-color:#343d42;color:#c2d4ca}
.principles .pr-localhint{color:#b7c8c0}
.principles .pr-state,.principles [data-role=detail]{border-color:#3c4b51}
.principles .pr-footnote{color:#9aafb0}
.workspace-actions [data-action=restart]{background:#223b31;border-color:#628f78;color:#cefae4}
.workspace-actions [data-action=restart]:hover{background:#315442}
.pr-operation .pr-exploration-guide,.operation-guide{font-weight:400}
@media(max-width:600px){.principles .pr-tabs button{border-radius:9px}.principles .pr-hud-head button{min-height:30px}}

/* Practice rewards and timed laboratory controls share the course palette. */
.header-wallet{color:#c9f5df;border-color:#567f6c;background:#203b31;white-space:nowrap}
.header-wallet b{font-variant-numeric:tabular-nums;margin-left:7px;color:#aaf0cb}
.practice-reward-banner,.challenge-bar{margin:0 0 18px;border:1px solid #4b685e;border-radius:14px;background:linear-gradient(115deg,#1b2c28,#18232a);padding:18px 20px;color:#d8eae3}
.practice-reward-banner{display:flex;align-items:center;justify-content:space-between;gap:20px}
.practice-reward-banner strong{font-weight:500;color:#b6edcf;font-size:15px}
.practice-reward-banner p{margin:5px 0 0;color:#a9bfb5;font-size:13px;line-height:1.7}
.practice-reward-banner[data-eligible=false]{background:#1b2226;border-color:#414e53}
.practice-reward-banner[data-eligible=false] strong{color:#c4d2d5}
.lab-wallet{display:flex;flex-direction:column;gap:1px;min-width:102px;text-align:right;white-space:nowrap;color:#a3beb1;font-size:12px}
.lab-wallet b{color:#acf1ca;font-size:29px;font-weight:500;line-height:1.3;font-variant-numeric:tabular-nums}
.home-wallet{border:1px solid #476858;border-radius:99px;padding:6px 14px;color:#aac5b7;font-size:13px}
.home-wallet b{font-size:18px;color:#b7f0d0;margin-left:9px;font-weight:500}
.challenge-overview{display:grid;grid-template-columns:minmax(0,1fr) 170px 108px;gap:22px;align-items:center}
.challenge-mode{display:block;font-size:11px;letter-spacing:.08em;color:#a6c4b8}
#challengeName{display:block;font-weight:500;font-size:20px;line-height:1.5;margin-top:2px}
#challengeStatus{margin:5px 0 0;font-size:13px;color:#b4c5c0;line-height:1.65}
.challenge-clock{border-left:1px solid #466153;padding-left:22px}
.challenge-clock>span{display:block;font-size:11px;color:#a6beb2}
.challenge-clock output{display:block;color:#b4f2d1;font:500 36px/1.35 ui-monospace,Consolas,monospace;font-variant-numeric:tabular-nums;letter-spacing:.04em}
.challenge-actions{display:flex;flex-wrap:wrap;gap:9px;margin-top:15px}
.challenge-actions button{min-height:40px;padding:7px 17px;font-size:13px}
.challenge-actions [data-economy=time]{background:#253a34;border-color:#557764;color:#d0f0df}
.challenge-actions [data-economy=hint]{background:#24343c;border-color:#526d7c;color:#d7e8f5}
.challenge-actions button:disabled{color:#798e86;background:#1c2824;border-color:#364c40}
.challenge-rules{margin:12px 0 0;font-size:11px;color:#93aaa0;line-height:1.7}
.challenge-bar[data-status=expired]{border-color:#a16e55;background:linear-gradient(110deg,#312821,#222728)}
.challenge-bar[data-status=expired] .challenge-clock output{color:#ffc294}
.challenge-bar[data-status=completed]{border-color:#70b494}
.challenge-bar[data-status=completed] .challenge-clock output{color:#c8e8d6}
.wallet-summary{display:grid;grid-template-columns:repeat(3,1fr);gap:12px;margin:15px 0 20px}
.wallet-summary>div{border:1px solid #425a4e;border-radius:10px;background:#1c2a24;padding:12px;color:#a9c3b4;font-size:12px}
.wallet-summary strong{display:block;color:#b8ebcd;font-size:27px;font-weight:500;font-variant-numeric:tabular-nums}
.wallet-history{margin:10px 0 20px;border-top:1px solid #3f5249;padding-top:13px;font-size:13px;color:#b4cdbf}
.wallet-history summary{cursor:pointer}.wallet-history ul{padding-left:20px}.wallet-history li{padding:4px 0}.wallet-history b{font-weight:500;color:#b6f0ca}
@media(max-width:760px){.challenge-overview{grid-template-columns:minmax(0,1fr) 120px;gap:13px}.challenge-overview>.lab-wallet{grid-column:1/-1;flex-direction:row;align-items:center;text-align:left;gap:9px}.challenge-overview>.lab-wallet b{font-size:20px}.challenge-clock{padding-left:15px}.challenge-clock output{font-size:28px}.practice-reward-banner,.challenge-bar{padding:14px}.practice-reward-banner{gap:12px}.lab-wallet b{font-size:25px}.site-header nav{gap:6px}.header-wallet{font-size:12px}#challengeName{font-size:18px}}
@media(max-width:480px){.site-header{flex-wrap:wrap}.site-header nav{width:100%;justify-content:flex-end}.site-header .header-wallet{margin-right:auto}.practice-reward-banner{align-items:flex-start}.practice-reward-banner strong{font-size:13px}.practice-reward-banner p{font-size:12px}.practice-reward-banner .lab-wallet{min-width:80px;font-size:10px}.challenge-actions{display:grid;grid-template-columns:1fr 1fr}.challenge-actions button{padding:8px 5px;font-size:12px}.challenge-actions button[hidden]{display:none}.challenge-rules{font-size:10px}.wallet-summary{gap:7px}.wallet-summary>div{padding:10px}.wallet-summary strong{font-size:23px}}

.passphrase-input{display:block;width:100%;margin:9px 0 0;padding:13px 15px;border:1px solid #4c6c5c;border-radius:10px;background:#111c17;color:#e1f0e8;font:inherit;letter-spacing:.1em}.passphrase-input:focus{outline:2px solid #8ad9b0;outline-offset:2px}.passphrase-feedback{min-height:1.7em;font-size:13px;color:#d5c6a1;margin:9px 0 16px}#moduleAccessForm,#pointsPassphraseForm{margin:8px 0}#moduleAccessSubmit{width:100%}

#achievementToast{position:fixed;z-index:180;left:22px;bottom:22px;display:flex;align-items:center;gap:13px;max-width:min(390px,calc(100vw - 32px));padding:12px 19px 12px 12px;border:1px solid #7aa18b;border-left:3px solid #bcdda5;border-radius:10px;background:linear-gradient(120deg,#203529f7,#141e1ff7);box-shadow:0 12px 44px #0009;color:#e6f3e8;opacity:0;transform:translateY(24px);pointer-events:none;transition:opacity .3s,transform .3s}#achievementToast.show{opacity:1;transform:translateY(0)}#achievementToast img{width:64px;height:64px;object-fit:cover;border:1px solid #728c77;border-radius:6px}#achievementToast div{display:flex;flex-direction:column;gap:5px}#achievementToast span{color:#b6dba5;font-size:11px;letter-spacing:.08em}#achievementToast strong{font-size:15px;font-weight:500}#achievementToast small{color:#a8bfae;font-size:11px;line-height:1.5}@media(max-width:520px){#achievementToast{left:12px;bottom:12px;max-width:calc(100vw - 24px)}}

.challenge-bar[data-status=review]{border-color:#729d87;background:linear-gradient(110deg,#20372b,#1a2928)}.challenge-bar[data-status=review] .challenge-clock output{font-family:inherit;font-size:28px;letter-spacing:0;color:#c1e1cc}.challenge-bar[data-status=paused]{border-color:#687d89}.challenge-bar[data-status=paused] .challenge-clock output{color:#b4c7d0}.challenge-actions button[hidden]{display:none}

/* Completed experiments no longer expose a clock or time-purchase controls. */
.challenge-clock[hidden]{display:none!important}

.achievement-library{--achievement-line:#34473f;--achievement-accent:#83dab4;color:#d6e3dc;background:#101916;border:1px solid #2e4138;border-radius:17px;padding:25px;font-family:"Microsoft YaHei",system-ui,sans-serif}
.achievement-library-header{display:flex;align-items:center;justify-content:space-between;gap:22px;padding-bottom:23px;border-bottom:1px solid var(--achievement-line)}
.achievement-eyebrow{display:block;font-size:10px;letter-spacing:.2em;color:#83b49d;margin-bottom:9px}.achievement-library-header h2{font-size:26px;line-height:1.2;margin:0 0 9px;font-weight:500;color:#eff7f2}.achievement-library-header p{font-size:12px;color:#93aa9e;margin:0}
.achievement-empty{text-align:center;padding:36px 20px 28px;color:#94aa9e}.achievement-empty>span{display:block;color:#779f89;font-size:34px;margin-bottom:15px}.achievement-empty p{font-size:15px;color:#c8dbcf;margin:0 0 9px}.achievement-empty small{font-size:12px;line-height:1.8;color:#859d8e}
.achievement-total{text-align:right;min-width:80px}.achievement-total strong{display:block;font-family:Arial,sans-serif;font-size:42px;font-weight:400;line-height:1;color:#a5e4c4}.achievement-total span{display:block;font-size:11px;margin-top:9px;color:#99b1a4}
.achievement-section{margin-top:26px}.achievement-section-heading{display:flex;align-items:baseline;justify-content:space-between;gap:14px;margin-bottom:12px}.achievement-section-heading h3{font-size:16px;font-weight:500;color:#e2ede7;margin:0}.achievement-section-heading>span{font-size:11px;white-space:nowrap;color:#8fa99b}.achievement-section-note{font-size:11px;line-height:1.8;margin:-1px 0 13px;color:#869e90}.achievement-grid{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:9px}
.achievement-card{display:flex;align-items:stretch;gap:12px;min-width:0;min-height:99px;padding:10px;border:1px solid #35463c;border-radius:9px;background:linear-gradient(105deg,#202f26,#18241e);box-shadow:0 3px 9px #00000012}.achievement-art{width:78px;min-width:78px;height:78px;position:relative;border-radius:6px;overflow:hidden;background:#0d1511;border:1px solid #607359}.achievement-art img{display:block;width:100%;height:100%;object-fit:cover}.achievement-state-icon{position:absolute;bottom:0;right:0;width:21px;height:19px;display:grid;place-items:center;background:#b2d19a;color:#173623;font-size:12px;border-radius:5px 0 0 0;font-family:Arial,sans-serif}.achievement-art-placeholder{display:grid;place-items:center;height:100%;font-size:25px;color:#829e8b}.achievement-card-copy{min-width:0;align-self:center;flex:1}.achievement-card-title{display:flex;align-items:baseline;gap:7px;flex-wrap:wrap}.achievement-card h4{font-size:13px;line-height:1.5;font-weight:500;margin:0;color:#e6eee8}.achievement-state{font-size:9px;color:#b6cfa2;white-space:nowrap}.achievement-card p{font-size:10px;line-height:1.7;color:#acbdb0;margin:4px 0 0}.achievement-date{display:block;font-size:9px;color:#829f8d;margin-top:7px}.achievement-card.is-unlocked{border-color:#526343}
@media(max-width:760px){.achievement-library{padding:20px}.achievement-grid{grid-template-columns:1fr}.achievement-card{min-height:93px}.achievement-art{width:72px;min-width:72px;height:72px}.achievement-card h4{font-size:14px}.achievement-card p{font-size:11px}.achievement-library-header h2{font-size:23px}.achievement-total strong{font-size:37px}}
@media(max-width:430px){.achievement-library{padding:15px;border-radius:11px}.achievement-library-header{gap:14px;padding-bottom:18px}.achievement-eyebrow{font-size:8px;letter-spacing:.14em}.achievement-library-header h2{font-size:21px}.achievement-library-header p{font-size:10px}.achievement-total{min-width:61px}.achievement-total strong{font-size:32px}.achievement-total span{font-size:9px}.achievement-section-heading h3{font-size:15px}.achievement-art{width:64px;min-width:64px;height:68px}.achievement-card{gap:10px;min-height:91px;padding:9px}.achievement-card-title{gap:5px}.achievement-card h4{font-size:13px}.achievement-card p{font-size:10px}}

/* Keyframes run on first insertion as well as consecutive unlocks. The manual
   popover shares the browser top layer with dialogs instead of sitting below. */
#achievementToast{z-index:1350;transition:none;animation:achievement-depart .2s ease-in both;overflow:hidden;box-sizing:border-box}
#achievementToast.show{animation:achievement-arrive .62s cubic-bezier(.2,.85,.2,1) both}
#achievementToast.show img{animation:achievement-icon-arrive .58s .08s cubic-bezier(.2,.9,.2,1.12) both}
#achievementToast.show::after{content:"";position:absolute;inset:0;pointer-events:none;background:linear-gradient(110deg,transparent 15%,#d7f5c22b 45%,transparent 65%);transform:translateX(-140%);animation:achievement-shine 1.1s .28s ease-out both}
#achievementToast[popover]{inset:auto auto 22px 22px;margin:0}
#achievementToast[popover]:not(:popover-open){display:none}
@keyframes achievement-arrive{0%{opacity:0;transform:translateY(30px) scale(.94)}65%{opacity:1;transform:translateY(-3px) scale(1.01)}100%{opacity:1;transform:translateY(0) scale(1)}}
@keyframes achievement-depart{from{opacity:1;transform:translateY(0)}to{opacity:0;transform:translateY(18px)}}
@keyframes achievement-icon-arrive{from{opacity:0;transform:scale(.6) rotate(-9deg)}to{opacity:1;transform:scale(1) rotate(0)}}
@keyframes achievement-shine{to{transform:translateX(140%)}}
@media(max-width:520px){#achievementToast[popover]{inset:auto auto calc(12px + env(safe-area-inset-bottom,0px)) 12px}}
@media(prefers-reduced-motion:reduce){#achievementToast,#achievementToast.show,#achievementToast.show img,#achievementToast.show::after{animation:none}#achievementToast:not(.show){opacity:0}}

.classroom-locked .site-header nav{visibility:hidden}.classroom-locked #homeBtn{pointer-events:none}.classroom-locked #mentorDock{display:none}.classroom-login{display:grid;grid-template-columns:1.15fr 1fr;gap:64px;align-items:center;max-width:1120px;margin:8vh auto 10vh;padding:32px}.login-intro h1{font-size:clamp(34px,4vw,58px);line-height:1.2;margin:20px 0}.login-intro>p{max-width:480px;color:#acc0b8;line-height:1.8}.login-features{display:flex;gap:10px;flex-wrap:wrap;margin-top:32px}.login-features span{border:1px solid #35463f;border-radius:24px;padding:8px 14px;color:#b0c6bd;font-size:13px}.login-card{background:linear-gradient(145deg,#1b2624,#101918);padding:36px;border:1px solid #3c5249;border-radius:24px;box-shadow:0 22px 80px #0004}.login-card h2{font-size:27px;margin:14px 0 28px}.login-card label,.password-form label{display:block;font-size:14px;color:#b8ccc3;margin:16px 0 8px}.login-card input,.password-form input{display:block;width:100%;margin-top:8px;padding:13px 14px;background:#0b1311;border:1px solid #43584e;border-radius:9px;color:#e8f5ef;font-size:16px;box-sizing:border-box}.login-card input:focus,.password-form input:focus{outline:2px solid #71d6ae;outline-offset:2px}.login-card .primary{width:100%;margin:10px 0 8px}.classroom-message{min-height:24px;color:#e8bd84;font-size:14px;line-height:1.6}.classroom-loading{min-height:50vh;display:grid;place-content:center;justify-items:center;color:#b1c8bf}.loading-orbit{width:34px;height:34px;border:2px solid #304c40;border-top-color:#78dfb4;border-radius:50%;animation:classroom-spin 1s linear infinite}@keyframes classroom-spin{to{transform:rotate(360deg)}}.classroom-user{display:flex;align-items:center;gap:10px}.classroom-user-name{font-size:13px;color:#b7cbbf}.classroom-save-status{font-size:11px;color:#83b99f}.classroom-save-status[data-status=offline],.classroom-save-status[data-status=conflict]{color:#efbd78}.classroom-account-button{max-width:180px;overflow:hidden;text-overflow:ellipsis;white-space:nowrap}.account-identity{display:flex;align-items:baseline;gap:16px;padding-bottom:18px;border-bottom:1px solid #35483f}.account-identity strong{font-size:24px}.account-identity span{color:#a9beb4}.classroom-callout{border-left:3px solid #71d5aa;padding:12px 16px;background:#6cda9d10;color:#c8dfd2}.student-dashboard-summary{display:grid;grid-template-columns:repeat(3,1fr);gap:14px}.student-dashboard-summary>div{background:#0b1311;border:1px solid #354b3e;border-radius:12px;padding:16px}.student-dashboard-summary span{display:block;color:#91ae9e;font-size:12px}.student-dashboard-summary strong{display:block;font-size:21px;margin-top:8px}.student-progress-list article{display:flex;justify-content:space-between;padding:12px 0;border-bottom:1px solid #2f4438}.student-progress-list span{color:#8aceb0}.classroom-home-strip{display:flex;align-items:center;justify-content:space-between;gap:16px;padding:16px 22px;border:1px solid #354b40;border-radius:14px;background:#11221a;margin-bottom:24px}.classroom-home-strip strong{display:block}.classroom-home-strip p{color:#91ae9f;font-size:13px;margin:5px 0 0}.classroom-footer-count{color:#78988a;font-variant-numeric:tabular-nums}.site-header nav{gap:8px;flex-wrap:wrap}.site-header nav button{padding-left:13px;padding-right:13px}@media(max-width:800px){.classroom-login{grid-template-columns:1fr;gap:25px;margin:3vh auto;padding:20px}.login-card{padding:24px}.login-features{margin-top:18px}.classroom-user-name{display:none}.student-dashboard-summary{grid-template-columns:1fr 1fr}.student-dashboard-summary>div:first-child{grid-column:1/-1}.classroom-home-strip{align-items:flex-start;flex-direction:column}.site-header nav button{font-size:12px;padding:8px}.classroom-account-button{max-width:110px}.classroom-save-status{display:none}}

.classroom-rollcall-notice{position:fixed;inset:86px 18px auto auto;margin:0;z-index:2147483000;width:min(380px,calc(100vw - 36px));box-sizing:border-box;padding:20px 22px;border:1px solid #82d9b8;border-left:4px solid #8cedc6;border-radius:14px;background:linear-gradient(140deg,#1b362d,#0d2019);color:#ecfff4;box-shadow:0 18px 65px #0009,0 0 25px #8de8c225;font-family:inherit;animation:classroom-call-appear .3s ease}.classroom-rollcall-notice .classroom-rollcall-kicker{display:block;font-size:11px;color:#91dcbc;letter-spacing:2px;margin-bottom:8px}.classroom-rollcall-notice strong{display:block;font-size:20px;line-height:1.5;font-weight:500}.classroom-rollcall-notice p{font-size:13px;color:#b5d9c8;line-height:1.8;margin:10px 0 16px}.classroom-rollcall-notice button{display:block;margin-left:auto;min-height:44px;padding:8px 18px;border:1px solid #76ba9e;border-radius:8px;background:#2c5644;color:#e4fff0;font:inherit;cursor:pointer;touch-action:manipulation}.classroom-rollcall-notice button:focus-visible{outline:2px solid #c6ffe3;outline-offset:3px}.classroom-rollcall-notice::backdrop{background:transparent;pointer-events:none}@keyframes classroom-call-appear{from{opacity:0;transform:translateY(-8px)}to{opacity:1;transform:translateY(0)}}@media(max-width:600px){.classroom-rollcall-notice{inset:12px 12px auto;width:calc(100vw - 24px);padding:17px}}@media(prefers-reduced-motion:reduce){.classroom-rollcall-notice{animation:none}}
.classroom-guest-link{display:block;margin-top:28px;padding:16px 18px;border:1px solid #668d7b;border-radius:12px;background:#a2ecc00d;color:#c9ebd9;text-decoration:none;font-size:16px}.classroom-guest-link span{display:block;margin-top:7px;font-size:12px;line-height:1.7;color:#9bbfac}.classroom-guest-link:hover{border-color:#a3dfbf;background:#a2ecc017}

.commerce-feedback{position:fixed;right:24px;bottom:24px;z-index:1250;display:flex;flex-direction:column;align-items:flex-end;gap:9px;max-width:min(360px,calc(100vw - 28px));pointer-events:none;font-family:inherit}
.commerce-feedback-live:empty{display:none}
.commerce-reaction{display:flex;align-items:center;gap:14px;min-width:260px;padding:18px 21px;border:1px solid rgba(130,234,201,.34);border-radius:18px;background:linear-gradient(125deg,rgba(30,47,44,.98),rgba(15,23,25,.98));box-shadow:0 16px 46px #0007,inset 0 1px 0 #ffffff0b;color:#f2fbf8;animation:commerce-arrive .48s cubic-bezier(.2,.9,.2,1) both}
.commerce-reaction-label{display:block;margin-bottom:7px;font-size:10px;font-weight:600;letter-spacing:.18em;color:#80dfc4}
.commerce-reaction-copy strong{display:block;font-size:22px;line-height:1.3;font-weight:600}
.commerce-reaction-copy p{margin:9px 0 0;font-size:12px;line-height:1.65;color:#b5c9c3}
.commerce-reaction-achievement{border-color:#d4b97472;background:linear-gradient(125deg,#303029fa,#142226fa)}
.commerce-reaction-achievement .commerce-reaction-label{color:#e7d298}
.commerce-reaction img{width:74px;height:92px;flex:0 0 74px;object-fit:cover;object-position:center;border:1px solid #ffffff20;border-radius:9px}
.commerce-sound-retry{pointer-events:auto;border:1px solid #7d9d9455;background:#18221ff5;color:#bfcdc8;padding:7px 11px;border-radius:20px;font:inherit;font-size:11px;cursor:pointer;box-shadow:0 5px 18px #0003}
.commerce-sound-retry:hover{border-color:#8de2c2;color:#f3fff9}
.commerce-sound-retry:focus-visible{outline:2px solid #b8f5d9;outline-offset:3px}
.commerce-feedback [hidden]{display:none!important}
@keyframes commerce-arrive{from{opacity:0;transform:translateY(9px)}to{opacity:1;transform:none}}
@media(max-width:600px){.commerce-feedback{right:14px;bottom:calc(14px + env(safe-area-inset-bottom,0px))}.commerce-reaction{padding:14px 16px;min-width:245px}.commerce-reaction-copy strong{font-size:20px}}
@media(prefers-reduced-motion:reduce){.commerce-reaction{animation:none}}

.commerce-feedback[popover]{inset:auto 24px 24px auto;margin:0;padding:0;border:0;overflow:visible;background:transparent;color:inherit}
.commerce-feedback[popover]:not(:popover-open){display:none}
.commerce-reaction-achievement{position:relative;overflow:hidden;animation:commerce-achievement-arrive .65s cubic-bezier(.2,.85,.2,1) both}
.commerce-reaction-achievement::after{content:"";position:absolute;inset:0;pointer-events:none;background:linear-gradient(110deg,transparent 15%,#f9e7ac24 45%,transparent 65%);transform:translateX(-140%);animation:commerce-achievement-shine 1.15s .35s ease-out both}
.commerce-reaction-achievement img{animation:commerce-achievement-icon .65s .08s cubic-bezier(.2,.9,.2,1.12) both}
@keyframes commerce-achievement-arrive{0%{opacity:0;transform:translateY(30px) scale(.94)}65%{opacity:1;transform:translateY(-3px) scale(1.01)}100%{opacity:1;transform:translateY(0) scale(1)}}
@keyframes commerce-achievement-shine{to{transform:translateX(140%)}}
@keyframes commerce-achievement-icon{from{opacity:0;transform:scale(.6) rotate(-9deg)}to{opacity:1;transform:scale(1) rotate(0)}}
@media(max-width:600px){.commerce-feedback[popover]{inset:auto 14px calc(14px + env(safe-area-inset-bottom,0px)) auto}}
@media(prefers-reduced-motion:reduce){.commerce-reaction,.commerce-reaction-achievement,.commerce-reaction-achievement img,.commerce-reaction-achievement::after{animation:none}}

.student-rewards{margin-top:24px;padding:24px;background:#111c18;border:1px solid #344b40;border-radius:16px;color:#d6e8dc}.rewards-heading{display:flex;align-items:center;justify-content:space-between;gap:18px}.rewards-heading h3{font-size:22px;font-weight:500;margin:6px 0 12px}.equipped-avatar{display:flex;align-items:center;gap:10px;font-size:12px}.equipped-avatar img,.classroom-account-avatar{width:42px;height:42px;border-radius:11px;object-fit:cover;border:1px solid #88b69b}.classroom-account-button{display:inline-flex;align-items:center;gap:8px}.classroom-account-avatar{width:30px;height:30px;border-radius:8px}.mentor-achievement-bonus{display:grid;grid-template-columns:1fr auto;gap:7px;margin:18px 0;padding:15px;border:1px solid #77965e;background:linear-gradient(110deg,#243723,#18291e);border-radius:10px}.mentor-achievement-bonus span{font-size:13px}.mentor-achievement-bonus strong{color:#c6e7a1;font-weight:500}.mentor-achievement-bonus small{color:#98b19b;font-size:11px;grid-column:1/-1}.blind-box-list{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:12px;margin:20px 0}.blind-box-card{display:flex;align-items:center;gap:16px;padding:20px 16px;border:1px solid #7e8d5f;border-radius:13px;background:radial-gradient(ellipse at 25% 50%,#43583966,transparent 70%),#19251d}.blind-box-card strong{font-size:14px;font-weight:500}.blind-box-card p{font-size:11px;color:#99b09f;margin:8px 0 13px}.blind-box-card button{font-size:12px;padding:8px 12px}.blind-box-symbol{position:relative;width:66px;min-width:66px;height:66px;display:grid;place-items:center;background:linear-gradient(135deg,#78824e,#3b543d);border:1px solid #a2b781;border-radius:10px;box-shadow:0 10px 22px #0006;transform:rotate(-7deg)}.blind-box-symbol::before{content:'';position:absolute;left:-3px;right:-3px;top:10px;height:11px;border:1px solid #bbcb96;background:#7a8f5c;border-radius:3px}.blind-box-symbol span{margin-top:14px;font:28px Georgia,serif;color:#e4eacb}.blind-box-card.is-opening .blind-box-symbol{animation:blind-box-shake .48s ease-in-out infinite alternate}.blind-box-reveal{display:flex;align-items:center;gap:20px;padding:22px;margin:18px 0;background:radial-gradient(ellipse at 20% 50%,#65845266,transparent 75%),#1a2a20;border:1px solid #a1be7e;border-radius:14px;animation:blind-box-reveal .72s cubic-bezier(.2,.8,.2,1) both}.blind-box-reveal img{width:108px;height:108px;object-fit:cover;border-radius:14px;border:2px solid #b6cf8d;box-shadow:0 0 30px #b2d59126}.blind-box-reveal div{display:flex;flex-direction:column;gap:10px}.blind-box-reveal span,.blind-box-reveal small{font-size:12px;color:#b4c999}.blind-box-reveal strong{font-size:20px;font-weight:500}.owned-avatar-grid{display:grid;grid-template-columns:repeat(4,minmax(0,1fr));gap:10px;margin-top:18px}.owned-avatar{display:flex;flex-direction:column;align-items:center;gap:7px;padding:12px 7px;border:1px solid #395143;border-radius:10px;background:#19271f;color:#c6dece;min-width:0}.owned-avatar img{width:64px;height:64px;object-fit:cover;border-radius:10px}.owned-avatar span{font-size:11px;line-height:1.5}.owned-avatar small{font-size:10px;color:#8ca797}.owned-avatar.is-equipped{opacity:1;border-color:#a2bf80;background:#273524}.rewards-notice{min-height:1.5em;margin-bottom:0}.lesson-ended-screen{max-width:760px;margin:70px auto;padding:50px 34px;border:1px solid #41584b;border-radius:20px;background:#15231c}.lesson-ended-screen h1{font-weight:500;font-size:34px}.lesson-ended-screen p{line-height:1.9;color:#a7bdaf}.lesson-ended-screen .inline{margin-top:28px}@keyframes blind-box-shake{from{transform:rotate(-10deg) translateY(-2px)}to{transform:rotate(10deg) translateY(2px)}}@keyframes blind-box-reveal{from{opacity:0;transform:translateY(16px) scale(.9)}to{opacity:1;transform:translateY(0) scale(1)}}@media(max-width:700px){.student-rewards{padding:18px}.blind-box-list{grid-template-columns:1fr}.owned-avatar-grid{grid-template-columns:repeat(3,minmax(0,1fr))}.blind-box-reveal img{width:80px;height:80px}.rewards-heading{align-items:flex-start}.equipped-avatar span{max-width:70px}.lesson-ended-screen{margin:35px 15px;padding:28px 24px}}@media(prefers-reduced-motion:reduce){.blind-box-card.is-opening .blind-box-symbol,.blind-box-reveal{animation:none}}

/* Course login only: retain normal document scroll at default zoom. */
body.classroom-locked{overflow-y:auto}
.classroom-login{grid-template-columns:minmax(0,1.15fr) minmax(0,1fr);gap:clamp(24px,4vw,64px)}
.classroom-login>.login-intro,.classroom-login>.login-card{min-width:0}
@media(max-width:800px){.classroom-login{grid-template-columns:minmax(0,1fr)}}
@media(max-height:700px){.classroom-login{margin:16px auto 24px;padding-top:16px;padding-bottom:16px;align-items:start}}