.auth-backdrop{position:fixed;inset:0;z-index:var(--z-modal);background:#0706038c;backdrop-filter:blur(5px);display:grid;place-items:center;padding:var(--sp-4);animation:cmdk-fade var(--dur-2) var(--ease-out-quart)}.auth-dialog{position:relative;width:min(420px,94vw);padding:var(--sp-6);display:flex;flex-direction:column;gap:var(--sp-3);background:var(--surface-2);border:1px solid var(--border-strong);border-radius:var(--r-lg);box-shadow:var(--sh-3);animation:cmdk-rise var(--dur-3) var(--ease-out-expo);text-align:center}.auth-close{position:absolute;top:var(--sp-3);right:var(--sp-3);color:var(--ink-3)}.auth-close:hover{color:var(--ink)}.auth-icon{align-self:center;display:grid;place-items:center;width:54px;height:54px;border-radius:50%;background:color-mix(in oklch,var(--brand) 16%,var(--surface-3));color:var(--brand-bright)}.auth-icon[data-tone=success]{background:color-mix(in oklch,var(--good) 18%,var(--surface-3));color:var(--good)}.auth-icon[data-tone=error]{background:color-mix(in 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svg{flex-shrink:0;margin-top:2px}.auth-switch{font-size:var(--fs-sm);color:var(--ink-3);display:flex;flex-direction:column;gap:6px;margin-top:var(--sp-2)}.auth-link{color:var(--brand-bright);font:inherit;display:inline-flex;align-items:center;gap:5px}.auth-link:hover{text-decoration:underline}.auth-link:disabled{opacity:.5}.acct{position:relative}.acct-skel{width:34px;height:34px;border-radius:50%;background:var(--surface-2)}.acct-trigger{position:relative;display:grid;place-items:center}.acct-avatar{display:grid;place-items:center;width:34px;height:34px;border-radius:50%;background:var(--surface-3);border:1px solid var(--border-strong);font-weight:600;font-size:var(--fs-sm);color:var(--ink)}.acct-avatar[data-admin]{border-color:color-mix(in oklch,var(--warn) 55%,var(--border));background:color-mix(in oklch,var(--warn) 18%,var(--surface-3));color:var(--warn)}.acct-syncdot{position:absolute;right:-1px;bottom:-1px;width:10px;height:10px;border-radius:50%;border:2px solid 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a:hover{color:var(--brand-bright)}.study-timer{display:flex;align-items:center;gap:var(--sp-2);padding:5px 8px 5px 11px;border:1px solid var(--border);border-radius:var(--r-md);background:var(--surface)}.study-timer[data-running=true]{border-color:color-mix(in oklch,var(--accent) 45%,var(--border))}.study-timer-icon{color:var(--accent)}.study-timer-clock{font-family:var(--font-mono);font-size:var(--fs-sm);font-weight:600;letter-spacing:.02em;color:var(--ink);font-variant-numeric:tabular-nums;min-width:44px}.study-timer-btn{display:grid;place-items:center;width:26px;height:26px;border-radius:var(--r-sm);color:var(--ink-2)}.study-timer-btn:hover:not(:disabled){background:var(--surface-2);color:var(--ink)}.study-timer-btn:disabled{opacity:.35;cursor:not-allowed}.cmdk-backdrop{position:fixed;inset:0;z-index:var(--z-modal);background:#0706038c;backdrop-filter:blur(3px);display:flex;align-items:flex-start;justify-content:center;padding-top:14vh;animation:cmdk-fade var(--dur-fast) var(--ease-out)}@keyframes cmdk-fade{0%{opacity:0}}.cmdk{width:min(620px,92vw);background:var(--surface-2);border:1px solid var(--border-strong);border-radius:var(--r-lg);box-shadow:var(--sh-3);overflow:hidden;animation:cmdk-rise var(--dur-3) var(--ease-out-expo)}@keyframes cmdk-rise{0%{transform:translateY(-12px) scale(.985);opacity:0}}.cmdk-input-row{display:flex;align-items:center;gap:var(--sp-3);padding:var(--sp-4) var(--sp-4);border-bottom:1px solid var(--border);color:var(--ink-3)}.cmdk-input-row input{flex:1;background:none;border:none;outline:none;font-size:1.05rem;color:var(--ink)}.cmdk-input-row input::placeholder{color:var(--ink-3)}.cmdk-input-row kbd{font-size:var(--fs-xs);padding:2px 7px;border:1px solid var(--border-strong);border-radius:var(--r-xs);color:var(--ink-3)}.cmdk-list{max-height:50vh;overflow-y:auto;padding:var(--sp-2)}.cmdk-empty{padding:var(--sp-6);text-align:center;color:var(--ink-3)}.cmdk-item{display:flex;align-items:center;gap:var(--sp-3);padding:var(--sp-2) var(--sp-3);border-radius:var(--r-sm);cursor:pointer}.cmdk-item[data-active=true]{background:var(--surface-3)}.cmdk-item-icon{display:grid;place-items:center;width:30px;height:30px;border-radius:var(--r-sm);background:var(--surface-3);color:var(--subject-ink, var(--ink-2));flex-shrink:0}.cmdk-item-text{display:flex;flex-direction:column;min-width:0;flex:1}.cmdk-item-label{font-weight:550;color:var(--ink)}.cmdk-item-sub{font-size:var(--fs-xs);color:var(--ink-3);overflow:hidden;text-overflow:ellipsis;white-space:nowrap;max-width:46ch}.cmdk-item-kind{font-size:var(--fs-xs);color:var(--ink-faint);text-transform:uppercase;letter-spacing:.04em}.cmdk-enter{color:var(--subject-ink, var(--brand))}.route-fallback{display:flex;flex-direction:column;align-items:center;justify-content:center;gap:var(--sp-4);height:60vh;color:var(--ink-3)}.route-fallback-pulse{width:38px;height:38px;border-radius:50%;border:3px solid var(--border);border-top-color:var(--subject, var(--brand));animation:spin .8s linear infinite}@keyframes spin{to{transform:rotate(360deg)}}@media (max-width: 640px){.app{grid-template-columns:1fr;grid-template-rows:1fr auto}.rail{grid-row:2;flex-direction:row;width:100%;height:60px;padding:0 var(--sp-3);border-right:none;border-top:1px solid var(--border);overflow-x:auto}.rail-brand,.rail-divider,.rail-spacer,.rail-cmd{display:none}.rail-group{flex-direction:row;width:auto}.rail-link.active:before{left:50%;top:auto;bottom:-4px;transform:translate(-50%);width:20px;height:3px}.rail-tip{display:none}.app-body{grid-row:1;height:auto;overflow:hidden}.topbar{gap:var(--sp-2);padding:0 var(--sp-3)}.breadcrumb{flex:1 1 0;min-width:0}.topbar-actions{flex-shrink:0;gap:var(--sp-2)}.study-timer{padding:4px 6px 4px 9px;gap:4px}.study-timer-reset{display:none}.study-timer-clock{min-width:38px;font-size:var(--fs-xs)}}:root{--bg: oklch(.18 .008 85);--bg-deep: oklch(.145 .008 85);--surface: oklch(.215 .008 85);--surface-2: oklch(.245 .009 85);--surface-3: oklch(.275 .01 85);--surface-hover: oklch(.275 .01 85);--border: oklch(.32 .01 85);--border-strong: oklch(.4 .012 85);--border-faint: oklch(.265 .009 85 / .85);--ink: oklch(.93 .012 85);--ink-1: oklch(.9 .012 85);--ink-2: oklch(.855 .012 85);--ink-3: oklch(.7 .012 85);--ink-faint: oklch(.56 .01 85);--accent: oklch(.7 .082 135);--accent-bright: oklch(.78 .095 135);--accent-fill: oklch(.6 .072 135);--accent-dim: oklch(.5 .055 135);--on-accent: oklch(.16 .01 135);--accent-wash: oklch(.7 .082 135 / .12);--brand: var(--accent);--brand-bright: var(--accent-bright);--brand-dim: var(--accent-dim);--good: oklch(.74 .09 150);--good-dim: oklch(.52 .07 150);--warn: oklch(.78 .095 75);--bad: oklch(.66 .115 35);--bad-dim: oklch(.48 .09 35);--good-wash: oklch(.74 .09 150 / .12);--warn-wash: oklch(.78 .095 75 / .12);--bad-wash: oklch(.66 .115 35 / .12);--physics: oklch(.7 .07 235);--physics-ink: oklch(.8 .075 235);--physics-bright: oklch(.8 .075 235);--physics-dim: oklch(.5 .05 235);--maths: oklch(.7 .085 25);--maths-ink: oklch(.8 .09 25);--maths-bright: oklch(.8 .09 25);--maths-dim: oklch(.5 .06 25);--fmaths: oklch(.71 .075 300);--fmaths-ink: oklch(.81 .08 300);--fmaths-bright: oklch(.81 .08 300);--fmaths-dim: oklch(.52 .055 300);--econ: oklch(.74 .085 95);--econ-ink: oklch(.83 .09 95);--econ-bright: oklch(.83 .09 95);--econ-dim: oklch(.54 .06 95);--subject: var(--accent);--subject-bright: var(--accent-bright);--subject-dim: var(--accent-dim);--subject-ink: var(--accent-bright);--subject-glow: transparent;--subject-hue: var(--accent);--subject-hue-ink: var(--accent-bright);--font-read: "Newsreader", Georgia, "Times New Roman", serif;--font-ui: 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cubic-bezier(.16, 1, .3, 1);--ease-in-out: var(--ease-io);--dur-micro: .14s;--dur-fast: .18s;--dur-base: .22s;--dur-list: .26s;--dur-accordion: .24s;--dur-1: .14s;--dur-2: .18s;--dur-3: .24s;--dur-4: .42s;--stagger: .04s;--z-base: 1;--z-raised: 10;--z-sticky: 30;--z-dropdown: 40;--z-backdrop: 50;--z-modal: 60;--z-toast: 70;--z-tooltip: 80;--z-cmdk: 60;--rail-w: 68px;--max-content: 1160px}[data-subject=physics]{--subject-hue: var(--physics);--subject-hue-ink: var(--physics-ink)}[data-subject=maths]{--subject-hue: var(--maths);--subject-hue-ink: var(--maths-ink)}[data-subject=fmaths]{--subject-hue: var(--fmaths);--subject-hue-ink: var(--fmaths-ink)}[data-subject=economics]{--subject-hue: var(--econ);--subject-hue-ink: var(--econ-ink)}[data-theme=light]{--bg: oklch(.95 .006 85);--bg-deep: oklch(.92 .006 85);--surface: oklch(.985 .005 85);--surface-2: oklch(.965 .006 85);--surface-3: oklch(.945 .007 85);--surface-hover: oklch(.945 .007 85);--border: oklch(.88 .008 85);--border-strong: oklch(.8 .01 85);--border-faint: oklch(.91 .006 85);--ink: oklch(.26 .014 85);--ink-1: oklch(.3 .014 85);--ink-2: oklch(.34 .014 85);--ink-3: oklch(.48 .012 85);--ink-faint: oklch(.58 .01 85);--accent: oklch(.48 .08 135);--accent-bright: oklch(.42 .085 135);--accent-fill: oklch(.46 .08 135);--accent-dim: oklch(.4 .07 135);--on-accent: oklch(.97 .006 135);--accent-wash: oklch(.48 .08 135 / .1);--good: oklch(.52 .09 150);--warn: oklch(.58 .095 75);--bad: oklch(.52 .12 35);--physics: oklch(.52 .08 235);--physics-ink: oklch(.46 .085 235);--maths: oklch(.52 .095 25);--maths-ink: oklch(.46 .1 25);--fmaths: oklch(.5 .08 300);--fmaths-ink: oklch(.44 .085 300);--econ: oklch(.54 .095 95);--econ-ink: oklch(.46 .1 95);--shadow-float: 0 1px 2px oklch(.55 .01 85 / .18), 0 8px 24px oklch(.55 .01 85 / .14)}*,*:before,*:after{box-sizing:border-box}*{margin:0;padding:0}html{-webkit-text-size-adjust:100%;scroll-behavior:smooth;scrollbar-gutter:stable}@media (prefers-reduced-motion: 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