@layer reset,tokens,base,layout,components,content,utilities,overrides;@layer reset{*,*:before,*:after{box-sizing:border-box;margin:0;padding:0}html{-webkit-text-size-adjust:100%;-moz-text-size-adjust:100%;text-size-adjust:100%;scroll-behavior:smooth;hanging-punctuation:first last}body{min-height:100dvh;-webkit-font-smoothing:antialiased;-moz-osx-font-smoothing:grayscale;text-rendering:optimizeLegibility}img,picture,video,canvas,svg{display:block;max-width:100%;height:auto}input,button,textarea,select{font:inherit;color:inherit}p,h1,h2,h3,h4,h5,h6{overflow-wrap:break-word}h1,h2,h3,h4,h5,h6{text-wrap:balance}p{text-wrap:pretty}a{color:inherit;text-decoration:none}ul,ol{list-style:none}:focus-visible{outline:2px solid var(--os-accent-primary);outline-offset:3px;border-radius:2px}.skip-link{position:absolute;top:-100%;left:0;z-index:9999;padding:1rem 2rem;background:var(--os-bg-primary);color:var(--os-text-primary);font-weight:600;transition:top .2s ease}.skip-link:focus{top:0}}@layer tokens{:root{--os-ref-warm-50: hsl(43, 50%, 98%);--os-ref-warm-100: hsl(40, 40%, 95%);--os-ref-warm-200: hsl(38, 35%, 90%);--os-ref-warm-300: hsl(35, 25%, 85%);--os-ref-warm-400: hsl(30, 15%, 68%);--os-ref-warm-500: hsl(30, 10%, 55%);--os-ref-warm-600: hsl(30, 8%, 42%);--os-ref-warm-700: hsl(30, 10%, 30%);--os-ref-warm-800: hsl(30, 12%, 20%);--os-ref-warm-900: hsl(30, 15%, 12%);--os-ref-gold-400: hsl(35, 80%, 52%);--os-ref-gold-500: hsl(33, 78%, 44%);--os-ref-gold-600: hsl(30, 75%, 36%);--os-ref-terra-400: hsl(18, 68%, 55%);--os-ref-terra-500: hsl(22, 72%, 48%);--os-ref-terra-600: hsl(20, 70%, 40%);--os-ref-sage-400: hsl(152, 42%, 48%);--os-ref-sage-500: hsl(152, 50%, 38%);--os-ref-sage-600: hsl(152, 48%, 30%);--os-ref-plum-400: hsl(265, 40%, 60%);--os-ref-plum-500: hsl(260, 45%, 50%);--os-ref-plum-600: hsl(258, 42%, 42%);--os-ref-red-400: hsl(6, 58%, 55%);--os-ref-red-500: hsl(4, 65%, 45%);--os-ref-red-600: hsl(2, 60%, 38%);--os-ref-win-blue: hsl(207, 75%, 42%);--os-ref-linux-orange: hsl(16, 70%, 48%);--os-ref-diff-beginner: hsl(152, 50%, 38%);--os-ref-diff-intermediate: hsl(33, 78%, 44%);--os-ref-diff-advanced: hsl(4, 65%, 45%);--os-ref-diff-expert: hsl(260, 45%, 50%);--os-ref-terminal-bg: hsl(220, 20%, 8%);--os-ref-terminal-header: hsl(220, 20%, 12%)}@supports (color: oklch(0% 0 0)){:root{--os-ref-gold-500: oklch(55% .14 60);--os-ref-terra-500: oklch(56% .14 35);--os-ref-sage-500: oklch(52% .12 160);--os-ref-plum-500: oklch(50% .15 295);--os-ref-red-500: oklch(50% .16 25);--os-ref-win-blue: oklch(48% .16 250)}}:root{--os-bg-primary: var(--os-ref-warm-50);--os-bg-secondary: var(--os-ref-warm-100);--os-bg-tertiary: var(--os-ref-warm-200);--os-bg-panel: hsla(42, 60%, 99%, .84);--os-bg-panel-strong: hsla(43, 70%, 99%, .94);--os-bg-accent-wash: linear-gradient(135deg, hsla(36, 82%, 60%, .14), hsla(262, 50%, 62%, .08));--os-body-glow: radial-gradient(circle at top left, hsla(36, 82%, 58%, .14), transparent 30%), radial-gradient(circle at 86% 12%, hsla(154, 44%, 35%, .08), transparent 24%);--os-body-surface: linear-gradient(180deg, hsla(36, 65%, 95%, .94), hsla(36, 52%, 92%, .98));--os-grid-line: hsla(31, 18%, 48%, .08);--os-panel-edge: hsla(33, 22%, 40%, .12);--os-bg-glass: hsla(40, 50%, 100%, .75);--os-glass-blur: 12px;--os-glass-border: 1px solid hsla(30, 30%, 60%, .18);--os-glass-border-hover: 1px solid hsla(33, 60%, 45%, .35);--os-color-windows: var(--os-ref-win-blue);--os-color-linux: var(--os-ref-linux-orange);--os-color-shared: var(--os-ref-warm-500);--os-zone-learn: hsl(154, 44%, 35%);--os-zone-learn-soft: hsla(154, 44%, 35%, .11);--os-zone-topics: hsl(187, 54%, 37%);--os-zone-topics-soft: hsla(187, 54%, 37%, .12);--os-zone-atlas: hsl(346, 58%, 42%);--os-zone-atlas-soft: hsla(346, 58%, 42%, .12);--os-zone-practice: hsl(262, 42%, 46%);--os-zone-practice-soft: hsla(262, 42%, 46%, .12);--os-zone-library: hsl(207, 68%, 42%);--os-zone-library-soft: hsla(207, 68%, 42%, .12);--os-zone-progress: hsl(33, 78%, 44%);--os-zone-progress-soft: hsla(33, 78%, 44%, .12);--os-accent-primary: var(--os-ref-gold-500);--os-accent-green: var(--os-ref-sage-500);--os-accent-purple: var(--os-ref-plum-500);--os-accent-amber: var(--os-ref-terra-500);--os-accent-danger: var(--os-ref-red-500);--os-accent-text: var(--os-ref-gold-600);--os-accent-fill: var(--os-ref-gold-400);--os-diff-beginner: var(--os-ref-diff-beginner);--os-diff-intermediate: var(--os-ref-diff-intermediate);--os-diff-advanced: var(--os-ref-diff-advanced);--os-diff-expert: var(--os-ref-diff-expert);--os-text-primary: var(--os-ref-warm-900);--os-text-secondary: var(--os-ref-warm-700);--os-text-muted: var(--os-ref-warm-600);--os-text-code: hsl(30, 55%, 32%);--os-border-subtle: var(--os-ref-warm-300);--os-border-default: var(--os-ref-warm-400);--os-shadow-sm: 0 2px 8px hsla(30, 20%, 40%, .07);--os-shadow-md: 0 8px 32px hsla(30, 20%, 40%, .09);--os-shadow-lg: 0 16px 64px hsla(30, 20%, 40%, .11);--os-shadow-glow: 0 0 20px hsla(33, 70%, 45%, .12);--os-shadow-soft: 0 18px 50px hsla(30, 28%, 24%, .08)}[data-theme=dark]{--os-bg-primary: hsl(230, 24%, 10%);--os-bg-secondary: hsl(230, 22%, 14%);--os-bg-tertiary: hsl(230, 20%, 18%);--os-bg-panel: hsla(230, 22%, 14%, .84);--os-bg-panel-strong: hsla(230, 24%, 12%, .94);--os-bg-accent-wash: linear-gradient(135deg, hsla(36, 82%, 50%, .08), hsla(262, 50%, 62%, .05));--os-body-glow: radial-gradient(circle at top left, hsla(36, 82%, 52%, .12), transparent 26%), radial-gradient(circle at 84% 10%, hsla(262, 50%, 62%, .12), transparent 22%);--os-body-surface: linear-gradient(180deg, hsl(230, 24%, 10%) 0%, hsl(230, 22%, 13%) 100%);--os-grid-line: hsla(230, 20%, 50%, .08);--os-panel-edge: hsla(230, 20%, 50%, .15);--os-bg-glass: hsla(230, 22%, 14%, .75);--os-glass-border: 1px solid hsla(230, 20%, 40%, .18);--os-glass-border-hover: 1px solid hsla(33, 60%, 55%, .35);--os-accent-primary: var(--os-ref-gold-400);--os-accent-green: var(--os-ref-sage-400);--os-accent-purple: var(--os-ref-plum-400);--os-accent-amber: var(--os-ref-terra-400);--os-accent-danger: var(--os-ref-red-400);--os-accent-text: var(--os-ref-gold-400);--os-accent-fill: var(--os-ref-gold-500);--os-text-primary: hsl(230, 15%, 95%);--os-text-secondary: hsl(230, 10%, 75%);--os-text-muted: hsl(230, 10%, 55%);--os-text-code: hsl(30, 85%, 75%);--os-border-subtle: hsl(230, 20%, 20%);--os-border-default: hsl(230, 20%, 28%);--os-shadow-sm: 0 2px 8px hsla(0, 0%, 0%, .2);--os-shadow-md: 0 8px 32px hsla(0, 0%, 0%, .3);--os-shadow-lg: 0 16px 64px hsla(0, 0%, 0%, .4);--os-shadow-glow: 0 0 20px hsla(33, 70%, 45%, .2);--os-shadow-soft: 0 18px 50px hsla(0, 0%, 0%, .4)}:root{--os-space-1: .25rem;--os-space-2: .5rem;--os-space-3: .75rem;--os-space-4: 1rem;--os-space-5: 1.25rem;--os-space-6: 1.5rem;--os-space-8: 2rem;--os-space-10: 2.5rem;--os-space-12: 3rem;--os-space-16: 4rem;--os-space-20: 5rem;--os-space-24: 6rem;--os-radius-sm: .375rem;--os-radius-md: .5rem;--os-radius-lg: .75rem;--os-radius-xl: 1rem;--os-radius-2xl: 1.5rem;--os-radius-full: 9999px;--os-ease-out: cubic-bezier(.16, 1, .3, 1);--os-ease-in-out: cubic-bezier(.65, 0, .35, 1);--os-ease-spring: cubic-bezier(.34, 1.56, .64, 1);--os-duration-fast: .15s;--os-duration-normal: .3s;--os-duration-slow: .5s;--os-z-behind: -1;--os-z-base: 0;--os-z-dropdown: 10;--os-z-sticky: 20;--os-z-overlay: 30;--os-z-modal: 40;--os-z-toast: 50;--os-z-tooltip: 60;--os-max-width: 1200px;--os-sidebar-width: 280px;--os-header-height: 64px}}@layer base{body{font-family:var(--os-font-ui);font-size:var(--os-font-size-base);line-height:var(--os-line-height);color:var(--os-text-primary);background-color:var(--os-bg-primary);background-image:var(--os-body-glow),var(--os-body-surface),linear-gradient(90deg,transparent 0,transparent calc(100% - 1px),var(--os-grid-line) calc(100% - 1px)),linear-gradient(0deg,transparent 0,transparent calc(100% - 1px),var(--os-grid-line) calc(100% - 1px));background-attachment:fixed,fixed,fixed,fixed;background-size:auto,auto,32px 32px,32px 32px}@media(prefers-reduced-motion:reduce){*,*:before,*:after{animation-duration:.01ms!important;animation-iteration-count:1!important;transition-duration:.01ms!important;scroll-behavior:auto!important}}@media(prefers-reduced-transparency:reduce){:root{--os-bg-glass: var(--os-bg-secondary);--os-glass-blur: 0px}}::selection{background:var(--os-accent-fill);color:#fff}::-webkit-scrollbar{width:8px;height:8px}::-webkit-scrollbar-track{background:var(--os-bg-secondary)}::-webkit-scrollbar-thumb{background:var(--os-ref-warm-400);border-radius:var(--os-radius-full)}::-webkit-scrollbar-thumb:hover{background:var(--os-ref-warm-500)}}@layer tokens{@font-face{font-family:Inter;src:url(/fonts/inter-variable-latin.woff2) format("woff2");font-weight:100 900;font-display:swap;font-style:normal;unicode-range:U+0000-00FF,U+0131,U+0152-0153,U+02BB-02BC,U+02C6,U+02DA,U+02DC,U+0304,U+0308,U+0329,U+2000-206F,U+20AC,U+2122,U+2191,U+2193,U+2212,U+2215,U+FEFF,U+FFFD}@font-face{font-family:JetBrains Mono;src:url(/fonts/jetbrains-mono-latin.woff2) format("woff2");font-weight:100 800;font-display:swap;font-style:normal;unicode-range:U+0000-00FF,U+0131,U+0152-0153,U+02BB-02BC,U+02C6,U+02DA,U+02DC,U+0304,U+0308,U+0329,U+2000-206F,U+20AC,U+2122,U+2191,U+2193,U+2212,U+2215,U+FEFF,U+FFFD}:root{--os-font-ui: "Inter", system-ui, -apple-system, "Segoe UI", Roboto, sans-serif;--os-font-display: "Inter", system-ui, sans-serif;--os-font-code: "JetBrains Mono", "Cascadia Code", "Fira Code", "Consolas", monospace;--os-font-size-xs: clamp(.6875rem, .65rem + .15vw, .75rem);--os-font-size-sm: clamp(.8125rem, .78rem + .15vw, .875rem);--os-font-size-base: clamp(.9375rem, .9rem + .18vw, 1rem);--os-font-size-md: clamp(1.0625rem, 1rem + .25vw, 1.125rem);--os-font-size-lg: clamp(1.25rem, 1.1rem + .5vw, 1.5rem);--os-font-size-xl: clamp(1.5rem, 1.3rem + .7vw, 1.875rem);--os-font-size-2xl: clamp(1.875rem, 1.5rem + 1.2vw, 2.5rem);--os-font-size-3xl: clamp(2.25rem, 1.8rem + 1.5vw, 3rem);--os-font-size-4xl: clamp(2.75rem, 2.2rem + 2vw, 3.75rem);--os-line-height: 1.7;--os-line-height-tight: 1.2;--os-line-height-snug: 1.4;--os-letter-spacing-tight: -.03em;--os-letter-spacing-normal: 0em;--os-letter-spacing-wide: .05em;--os-letter-spacing-display: -.045em}@font-face{font-family:Inter Fallback;src:local("Arial");size-adjust:107%;ascent-override:90%;descent-override:22%;line-gap-override:0%}}@layer base{h1,h2,h3,h4,h5,h6{font-family:var(--os-font-display);font-weight:700;font-variation-settings:"opsz" 32,"wght" 720;line-height:var(--os-line-height-tight);letter-spacing:var(--os-letter-spacing-display);color:var(--os-text-primary)}h1{font-size:clamp(3rem,2.3rem + 2.2vw,4.75rem);font-weight:820;line-height:.96}h2{font-size:clamp(2.2rem,1.7rem + 1.5vw,3.4rem)}h3{font-size:clamp(1.75rem,1.35rem + 1vw,2.4rem)}h4{font-size:var(--os-font-size-xl)}h5{font-size:var(--os-font-size-lg)}h6{font-size:var(--os-font-size-md);font-weight:600}p{font-size:var(--os-font-size-base);line-height:1.8;color:var(--os-text-secondary);max-width:72ch}a{color:var(--os-accent-text);text-decoration:none;transition:color var(--os-duration-fast) var(--os-ease-out)}a:hover{color:var(--os-ref-gold-600);text-decoration:underline;text-underline-offset:3px}code,kbd,samp,pre{font-family:var(--os-font-code);font-size:.9em}code:not(pre code){padding:.125em .375em;background:#b3854d1a;border:1px solid hsla(33,30%,50%,.15);border-radius:var(--os-radius-sm);color:var(--os-text-code);font-size:var(--os-font-size-sm)}kbd{padding:.125em .5em;background:var(--os-bg-secondary);border:1px solid var(--os-border-subtle);border-radius:var(--os-radius-sm);font-size:var(--os-font-size-sm);box-shadow:0 1px 0 var(--os-border-default)}blockquote{padding-left:var(--os-space-4);border-left:3px solid var(--os-accent-primary);color:var(--os-text-secondary);font-style:italic}strong{font-weight:600;color:var(--os-text-primary)}small{font-size:var(--os-font-size-sm);color:var(--os-text-muted)}.content ul,.content ol{padding-left:var(--os-space-6)}.content ul{list-style-type:disc}.content ol{list-style-type:decimal}.content li{margin-bottom:var(--os-space-2);line-height:var(--os-line-height);color:var(--os-text-secondary)}.content li::marker{color:var(--os-accent-text)}}@layer tokens{@keyframes fadeIn{0%{opacity:0}to{opacity:1}}@keyframes fadeInUp{0%{opacity:0;transform:translateY(20px)}to{opacity:1;transform:translateY(0)}}@keyframes fadeInDown{0%{opacity:0;transform:translateY(-20px)}to{opacity:1;transform:translateY(0)}}@keyframes slideInLeft{0%{opacity:0;transform:translate(-30px)}to{opacity:1;transform:translate(0)}}@keyframes slideInRight{0%{opacity:0;transform:translate(30px)}to{opacity:1;transform:translate(0)}}@keyframes glowPulse{0%,to{box-shadow:0 0 20px #c37b221a}50%{box-shadow:0 0 40px #c37b2233}}@keyframes cursorBlink{0%,50%{opacity:1}51%,to{opacity:0}}@keyframes shimmerLoad{0%{background-position:-200% 0}to{background-position:200% 0}}@keyframes scaleIn{0%{opacity:0;transform:scale(.95)}to{opacity:1;transform:scale(1)}}@keyframes float{0%,to{transform:translateY(0)}50%{transform:translateY(-8px)}}@keyframes typewriter{0%{width:0}to{width:100%}}@keyframes gradientShift{0%{background-position:0% 50%}50%{background-position:100% 50%}to{background-position:0% 50%}}}@layer utilities{.animate-fade-in{animation:fadeIn var(--os-duration-normal) var(--os-ease-out) both}.animate-fade-in-up{animation:fadeInUp var(--os-duration-slow) var(--os-ease-out) both}.animate-fade-in-down{animation:fadeInDown var(--os-duration-slow) var(--os-ease-out) both}.animate-slide-in-left{animation:slideInLeft var(--os-duration-slow) var(--os-ease-out) both}.animate-slide-in-right{animation:slideInRight var(--os-duration-slow) var(--os-ease-out) both}.animate-scale-in{animation:scaleIn var(--os-duration-normal) var(--os-ease-spring) both}.animate-glow{animation:glowPulse 3s ease-in-out infinite}.animate-float{animation:float 4s ease-in-out infinite}.animate-shimmer{background:linear-gradient(90deg,var(--os-bg-secondary) 25%,var(--os-bg-tertiary) 50%,var(--os-bg-secondary) 75%);background-size:200% 100%;animation:shimmerLoad 1.5s linear infinite}.stagger-children>*{animation:fadeInUp var(--os-duration-slow) var(--os-ease-out) both}.stagger-children>*:nth-child(1){animation-delay:0ms}.stagger-children>*:nth-child(2){animation-delay:80ms}.stagger-children>*:nth-child(3){animation-delay:.16s}.stagger-children>*:nth-child(4){animation-delay:.24s}.stagger-children>*:nth-child(5){animation-delay:.32s}.stagger-children>*:nth-child(6){animation-delay:.4s}.stagger-children>*:nth-child(7){animation-delay:.48s}.cursor-blink:after{content:"▌";animation:cursorBlink 1s step-end infinite;color:#3cdd7f}@supports (animation-timeline: scroll()){.animate-on-scroll{animation:fadeInUp linear both;animation-timeline:view();animation-range:entry 0% entry 100%}}}@layer components{.os-glass-card{--_bg: var(--os-bg-glass);--_blur: var(--os-glass-blur);--_border: var(--os-glass-border);--_radius: var(--os-radius-lg);--_shadow: var(--os-shadow-md);--_padding: var(--os-space-6);background:var(--_bg);background-image:var(--os-bg-accent-wash);backdrop-filter:blur(var(--_blur));-webkit-backdrop-filter:blur(var(--_blur));border:var(--_border);border-radius:var(--_radius);box-shadow:var(--_shadow),inset 0 1px #ffffff8c;padding:var(--_padding);transition:border-color var(--os-duration-fast) var(--os-ease-out),box-shadow var(--os-duration-fast) var(--os-ease-out),transform var(--os-duration-fast) var(--os-ease-out)}.os-glass-card:hover{border:var(--os-glass-border-hover);box-shadow:var(--os-shadow-glow)}.os-glass-card--elevated{--_bg: hsla(40, 45%, 99%, .85);--_shadow: var(--os-shadow-lg)}.os-glass-card--flat{--_bg: var(--os-bg-secondary);--_blur: 0px;--_shadow: none}.os-glass-card--interactive:hover{transform:translateY(-2px)}.os-btn{--_bg: linear-gradient(135deg, color-mix(in srgb, var(--os-accent-primary) 92%, white), color-mix(in srgb, var(--os-accent-amber) 82%, var(--os-accent-primary)));--_color: white;--_size-py: var(--os-space-3);--_size-px: var(--os-space-6);--_radius: var(--os-radius-md);display:inline-flex;align-items:center;justify-content:center;gap:var(--os-space-2);padding:var(--_size-py) var(--_size-px);background:var(--_bg);color:var(--_color);font-family:var(--os-font-ui);font-size:var(--os-font-size-sm);font-weight:600;line-height:1;border:1px solid transparent;box-shadow:0 14px 30px #815c311f,inset 0 1px #ffffff61;border-radius:var(--_radius);cursor:pointer;text-decoration:none;white-space:nowrap;transition:background var(--os-duration-fast) var(--os-ease-out),transform var(--os-duration-fast) var(--os-ease-out),box-shadow var(--os-duration-fast) var(--os-ease-out)}.os-btn:hover{transform:translateY(-2px);box-shadow:0 18px 36px #815c3129,inset 0 1px #ffffff6b}.os-btn:active{transform:translateY(0)}.os-btn:disabled,.os-btn[aria-disabled=true]{cursor:not-allowed;opacity:.68;transform:none;box-shadow:inset 0 1px #ffffff59}.os-btn:disabled:hover,.os-btn[aria-disabled=true]:hover{transform:none;box-shadow:inset 0 1px #ffffff59}.os-btn--secondary{--_bg: rgba(255, 255, 255, .6);--_color: var(--os-accent-text);border-color:color-mix(in srgb,var(--os-accent-primary) 34%,white);box-shadow:inset 0 1px #fff9}.os-btn--secondary:hover{--_bg: hsla(33, 78%, 44%, .08)}.os-btn--ghost{--_bg: rgba(255, 255, 255, .55);--_color: var(--os-text-secondary);box-shadow:inset 0 1px #ffffff80}.os-btn--ghost:hover{--_bg: var(--os-bg-tertiary);--_color: var(--os-text-primary)}.os-btn--danger{--_bg: var(--os-accent-danger);--_color: white}.os-btn--sm{--_size-py: var(--os-space-2);--_size-px: var(--os-space-4);font-size:var(--os-font-size-xs)}.os-btn--lg{--_size-py: var(--os-space-4);--_size-px: var(--os-space-8);font-size:var(--os-font-size-base)}.os-badge{display:inline-flex;align-items:center;gap:var(--os-space-1);padding:var(--os-space-1) var(--os-space-3);font-family:var(--os-font-code);font-size:var(--os-font-size-xs);font-weight:600;letter-spacing:var(--os-letter-spacing-wide);text-transform:uppercase;border-radius:var(--os-radius-full);line-height:1.4}.os-badge--windows{background:#1b73bb1a;color:var(--os-color-windows);border:1px solid hsla(207,75%,42%,.25)}.os-badge--linux{background:#d052251a;color:var(--os-color-linux);border:1px solid hsla(16,70%,48%,.25)}.os-badge--both{background:#c8791914;color:var(--os-accent-text);border:1px solid hsla(33,78%,44%,.2)}.os-terminal{--_bg: var(--os-ref-terminal-bg);--_radius: var(--os-radius-lg);background:var(--_bg);border:1px solid hsla(220,20%,25%,.4);border-radius:var(--_radius);overflow:hidden;font-family:var(--os-font-code);font-size:var(--os-font-size-sm);box-shadow:var(--os-shadow-md)}.os-terminal__header{display:flex;align-items:center;gap:var(--os-space-2);padding:var(--os-space-2) var(--os-space-4);background:var(--os-ref-terminal-header);border-bottom:1px solid 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#6c46b92e}.drill__back-btn{display:inline-flex;align-items:center;padding:.75rem 2rem;border:1px solid var(--os-border-subtle);border-radius:10px;color:var(--os-text-secondary);font-weight:600;text-decoration:none;transition:all .2s}.drill__back-btn:hover{border-color:var(--os-border-default);color:var(--os-text-primary)}@media(max-width:640px){.cmd-table__grid{grid-template-columns:1fr}.cmd-table__filter-row{flex-direction:column}.drill__summary-stats{grid-template-columns:repeat(2,1fr)}.drill__summary-actions{flex-direction:column}}@media(max-width:480px){.cmd-card{padding:1rem}.drill__setup,.drill__question-card,.drill__summary{padding:1.25rem}.drill__task-text{font-size:1.05rem}}}@layer tokens{:root{--os-surface-base: hsla(40, 50%, 100%, .84);--os-surface-muted: hsla(40, 35%, 97%, .88);--os-surface-elevated: hsla(42, 64%, 99%, .94);--os-surface-border: color-mix(in srgb, var(--os-panel-edge) 72%, white);--os-surface-border-strong: color-mix(in srgb, var(--os-panel-edge) 46%, white);--os-surface-shadow-soft: 0 14px 34px hsla(31, 24%, 24%, .07);--os-surface-shadow-strong: 0 22px 56px hsla(31, 26%, 18%, .1);--os-field-bg: hsla(42, 55%, 99%, .96);--os-field-border: color-mix(in srgb, var(--os-border-subtle) 80%, white);--os-field-border-strong: color-mix(in srgb, var(--os-accent-primary) 30%, white);--os-field-shadow-focus: 0 0 0 4px color-mix(in srgb, var(--os-accent-primary) 14%, transparent);--os-pill-bg: color-mix(in srgb, white 86%, var(--os-bg-secondary));--os-pill-border: color-mix(in srgb, var(--os-border-subtle) 72%, white);--os-status-verified: var(--os-accent-green);--os-status-reviewed: var(--os-ref-warm-500);--os-status-beginner-safe: var(--os-accent-green);--os-status-stretch: var(--os-zone-progress);--os-status-specialist: var(--os-ref-warm-600);--os-status-follow-order: var(--os-zone-progress);--os-status-recommended-order: var(--os-zone-progress);--os-status-direct-entry: var(--os-zone-learn);--os-status-guided: var(--os-zone-learn);--os-status-sandboxed: var(--os-zone-practice);--os-status-operational: var(--os-zone-progress);--os-status-overview: var(--os-zone-learn);--os-status-balanced-reference: var(--os-zone-library);--os-status-deep-reference: var(--os-zone-library);--os-status-ready: var(--os-zone-learn);--os-status-prep: var(--os-zone-progress);--os-status-review: var(--os-zone-library);--os-status-done: var(--os-accent-green);--os-status-next: var(--os-zone-progress)}[data-theme=dark]{--os-surface-base: hsla(230, 22%, 16%, .84);--os-surface-muted: hsla(230, 22%, 19%, .9);--os-surface-elevated: hsla(230, 24%, 14%, .96);--os-surface-border: color-mix(in srgb, var(--os-border-subtle) 90%, white);--os-surface-border-strong: color-mix(in srgb, var(--os-border-default) 76%, white);--os-surface-shadow-soft: 0 18px 40px hsla(0, 0%, 0%, .24);--os-surface-shadow-strong: 0 24px 60px hsla(0, 0%, 0%, .34);--os-field-bg: hsla(230, 22%, 14%, .94);--os-field-border: color-mix(in srgb, var(--os-border-default) 92%, white);--os-field-border-strong: color-mix(in srgb, var(--os-accent-primary) 36%, white);--os-field-shadow-focus: 0 0 0 4px color-mix(in srgb, var(--os-accent-primary) 18%, transparent);--os-pill-bg: color-mix(in srgb, var(--os-bg-secondary) 82%, white);--os-pill-border: color-mix(in srgb, var(--os-border-default) 86%, white)}}@layer components{.os-btn,.os-glass-card,.os-pill,.os-surface-link,.os-choice-card{--os-component-tone: var(--os-accent-primary);--os-component-tone-border: color-mix(in srgb, var(--os-component-tone) 18%, var(--os-surface-border))}.app-shell[data-zone=learn] :is(.os-btn[data-tone=context],.os-glass-card[data-tone=context],.os-pill[data-tone=context],.os-surface-link[data-tone=context],.os-choice-card[data-tone=context]){--os-component-tone: var(--os-zone-learn)}.app-shell[data-zone=topics] :is(.os-btn[data-tone=context],.os-glass-card[data-tone=context],.os-pill[data-tone=context],.os-surface-link[data-tone=context],.os-choice-card[data-tone=context]){--os-component-tone: var(--os-zone-topics)}.app-shell[data-zone=atlas] :is(.os-btn[data-tone=context],.os-glass-card[data-tone=context],.os-pill[data-tone=context],.os-surface-link[data-tone=context],.os-choice-card[data-tone=context]){--os-component-tone: var(--os-zone-atlas)}.app-shell[data-zone=practice] :is(.os-btn[data-tone=context],.os-glass-card[data-tone=context],.os-pill[data-tone=context],.os-surface-link[data-tone=context],.os-choice-card[data-tone=context]){--os-component-tone: var(--os-zone-practice)}.app-shell[data-zone=library] :is(.os-btn[data-tone=context],.os-glass-card[data-tone=context],.os-pill[data-tone=context],.os-surface-link[data-tone=context],.os-choice-card[data-tone=context]){--os-component-tone: var(--os-zone-library)}.app-shell[data-zone=progress] :is(.os-btn[data-tone=context],.os-glass-card[data-tone=context],.os-pill[data-tone=context],.os-surface-link[data-tone=context],.os-choice-card[data-tone=context]){--os-component-tone: var(--os-zone-progress)}:is(.os-btn,.os-glass-card,.os-pill,.os-surface-link,.os-choice-card)[data-tone=learn]{--os-component-tone: var(--os-zone-learn)}:is(.os-btn,.os-glass-card,.os-pill,.os-surface-link,.os-choice-card)[data-tone=practice]{--os-component-tone: var(--os-zone-practice)}:is(.os-btn,.os-glass-card,.os-pill,.os-surface-link,.os-choice-card)[data-tone=atlas]{--os-component-tone: var(--os-zone-atlas)}:is(.os-btn,.os-glass-card,.os-pill,.os-surface-link,.os-choice-card)[data-tone=library]{--os-component-tone: var(--os-zone-library)}:is(.os-btn,.os-glass-card,.os-pill,.os-surface-link,.os-choice-card)[data-tone=progress]{--os-component-tone: var(--os-zone-progress)}:is(.os-btn,.os-glass-card,.os-pill,.os-surface-link,.os-choice-card)[data-tone=success]{--os-component-tone: var(--os-accent-green)}:is(.os-btn,.os-glass-card,.os-pill,.os-surface-link,.os-choice-card)[data-tone=danger]{--os-component-tone: var(--os-accent-danger)}:is(.os-btn,.os-glass-card,.os-pill,.os-surface-link,.os-choice-card)[data-tone=neutral]{--os-component-tone: var(--os-ref-warm-500)}.os-glass-card{background-color:var(--_bg, var(--os-surface-base));background-image:radial-gradient(circle at top right,color-mix(in srgb,var(--os-component-tone) 11%,white),transparent 56%),linear-gradient(180deg,rgba(255,255,255,.12),transparent 42%);border-color:var(--os-component-tone-border);box-shadow:var(--os-surface-shadow-soft),inset 0 1px #ffffff8c}.os-glass-card--flat{--_bg: var(--os-surface-muted)}.os-glass-card--elevated{--_bg: var(--os-surface-elevated)}.os-btn{background:linear-gradient(135deg,color-mix(in srgb,var(--os-component-tone) 88%,white),color-mix(in srgb,var(--os-component-tone) 72%,var(--os-accent-amber)));box-shadow:0 14px 30px color-mix(in srgb,var(--os-component-tone) 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var(--os-ease-out),box-shadow var(--os-duration-fast) var(--os-ease-out),border-color var(--os-duration-fast) var(--os-ease-out)}.os-guidance-link:hover{text-decoration:none;transform:translateY(-1px);box-shadow:var(--os-shadow-sm);border-color:color-mix(in srgb,var(--os-accent-primary) 18%,white)}.os-guidance-link strong{display:inline-flex;flex-wrap:wrap;align-items:center;gap:.45rem;color:var(--os-text-primary)}.os-guidance-link small{color:var(--os-text-muted)}.os-reading-surface{display:grid;gap:var(--os-space-5)}.os-reading-prose{display:grid;gap:var(--os-space-4)}.os-reading-prose h2{margin-top:var(--os-space-10);margin-bottom:var(--os-space-4);padding-bottom:var(--os-space-3);border-bottom:1px solid var(--os-border-subtle)}.os-reading-prose h3{margin-top:var(--os-space-8);margin-bottom:var(--os-space-3)}.os-reading-prose p,.os-reading-prose li{font-size:var(--os-font-size-base);line-height:1.78;max-width:70ch}.os-reading-prose ul,.os-reading-prose 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65%,white)}.os-data-note{margin:0;font-size:var(--os-font-size-sm);line-height:1.72;color:var(--os-text-secondary);max-width:76ch}.os-card-stack{display:grid;gap:var(--os-space-4);align-content:start}.os-action-row{display:flex;flex-wrap:wrap;gap:var(--os-space-3)}.os-pill-row,.os-meta-wrap{display:flex;flex-wrap:wrap;gap:var(--os-space-2)}@media(max-width:900px){.os-data-toolbar{grid-template-columns:1fr}}}