:root{--color-primary: #6366f1;--color-primary-light: #818cf8;--color-primary-dark: #4f46e5;--color-primary-glow: rgba(99, 102, 241, .4);--color-secondary: #06b6d4;--color-secondary-light: #22d3ee;--color-secondary-dark: #0891b2;--color-secondary-glow: rgba(6, 182, 212, .4);--color-accent: #f472b6;--color-accent-light: #f9a8d4;--color-accent-dark: #ec4899;--color-accent-glow: rgba(244, 114, 182, .4);--color-success: #10b981;--color-success-glow: rgba(16, 185, 129, .3);--color-warning: #f59e0b;--color-warning-glow: rgba(245, 158, 11, .3);--color-error: #ef4444;--color-error-glow: rgba(239, 68, 68, .3);--color-bg-primary: #0f172a;--color-bg-secondary: #1e293b;--color-bg-tertiary: #334155;--color-bg-elevated: rgba(30, 41, 59, .8);--color-text-primary: #ffffff;--color-text-secondary: #f1f5f9;--color-text-muted: #cbd5e1;--color-text-inverse: #f8fafc;--color-border: rgba(148, 163, 184, .2);--color-border-light: rgba(148, 163, 184, .1);--color-border-focus: rgba(99, 102, 241, .5);--font-sans: "Inter", system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;--font-display: "Cal Sans", "Inter", sans-serif;--font-mono: "JetBrains Mono", "Fira Code", "Cascadia Code", monospace;--text-xs: .75rem;--text-sm: .875rem;--text-base: 1rem;--text-lg: 1.125rem;--text-xl: 1.25rem;--text-2xl: 1.5rem;--text-3xl: 1.875rem;--text-4xl: 2.25rem;--text-5xl: 3rem;--text-6xl: 3.75rem;--line-height-tight: 1.25;--line-height-normal: 1.5;--line-height-relaxed: 1.75;--space-1: .25rem;--space-2: .5rem;--space-3: .75rem;--space-4: 1rem;--space-5: 1.25rem;--space-6: 1.5rem;--space-8: 2rem;--space-10: 2.5rem;--space-12: 3rem;--space-16: 4rem;--space-20: 5rem;--space-24: 6rem;--shadow-sm: 0 1px 2px 0 rgb(0 0 0 / .3);--shadow-md: 0 4px 6px -1px rgb(0 0 0 / .4), 0 2px 4px -2px rgb(0 0 0 / .4);--shadow-lg: 0 10px 15px -3px rgb(0 0 0 / .4), 0 4px 6px -4px rgb(0 0 0 / .4);--shadow-xl: 0 20px 25px -5px rgb(0 0 0 / .5), 0 8px 10px -6px rgb(0 0 0 / .5);--shadow-glow: 0 0 40px -10px var(--color-primary-glow);--shadow-glow-secondary: 0 0 40px -10px var(--color-secondary-glow);--glass-bg: rgba(30, 41, 59, .6);--glass-bg-light: rgba(30, 41, 59, .4);--glass-border: rgba(255, 255, 255, .1);--glass-blur: blur(20px);--radius-sm: .375rem;--radius-md: .5rem;--radius-lg: .75rem;--radius-xl: 1rem;--radius-2xl: 1.5rem;--radius-3xl: 2rem;--radius-full: 9999px;--transition-fast: .15s cubic-bezier(.4, 0, .2, 1);--transition-normal: .25s cubic-bezier(.4, 0, .2, 1);--transition-slow: .35s cubic-bezier(.4, 0, .2, 1);--transition-bounce: .5s cubic-bezier(.68, -.55, .265, 1.55);--focus-ring: 0 0 0 3px var(--color-primary-glow);--gradient-primary: linear-gradient(135deg, var(--color-primary) 0%, var(--color-secondary) 100%);--gradient-accent: linear-gradient(135deg, var(--color-accent) 0%, var(--color-primary) 100%);--gradient-dark: linear-gradient(180deg, var(--color-bg-primary) 0%, var(--color-bg-secondary) 100%);--gradient-mesh: radial-gradient(ellipse at top, var(--color-primary-glow) 0%, transparent 50%), radial-gradient(ellipse at bottom right, var(--color-secondary-glow) 0%, transparent 50%), radial-gradient(ellipse at bottom left, var(--color-accent-glow) 0%, transparent 50%);--direction: ltr}*,*:before,*:after{box-sizing:border-box;margin:0;padding:0;user-select:none;-webkit-user-select:none;-moz-user-select:none;-ms-user-select:none}html{font-size:16px;-webkit-font-smoothing:antialiased;-moz-osx-font-smoothing:grayscale;scroll-behavior:smooth}body{font-family:var(--font-sans);font-size:var(--text-base);line-height:var(--line-height-normal);color:var(--color-text-primary);background:var(--color-bg-primary);min-height:100vh;overflow-x:hidden}body:before{content:"";position:fixed;inset:0;background:var(--gradient-mesh);pointer-events:none;z-index:-1;animation:meshMove 20s ease-in-out infinite}@keyframes meshMove{0%,to{opacity:.5;transform:scale(1)}50%{opacity:.8;transform:scale(1.1)}}h1,h2,h3,h4,h5,h6{font-weight:700;line-height:var(--line-height-tight);color:var(--color-text-primary);letter-spacing:-.02em}h1{font-size:var(--text-5xl)}h2{font-size:var(--text-4xl)}h3{font-size:var(--text-3xl)}h4{font-size:var(--text-2xl)}h5{font-size:var(--text-xl)}h6{font-size:var(--text-lg)}p{margin-bottom:var(--space-4);color:var(--color-text-secondary)}a{color:var(--color-primary-light);text-decoration:none;transition:all var(--transition-fast);position:relative}a:after{content:"";position:absolute;bottom:-2px;left:0;width:0;height:2px;background:var(--gradient-primary);transition:width var(--transition-normal)}a:hover{color:var(--color-text-primary)}a:hover:after{width:100%}a:focus-visible{outline:none;box-shadow:var(--focus-ring);border-radius:var(--radius-sm)}button{font-family:inherit;cursor:pointer;border:none;background:none;transition:all var(--transition-fast)}.btn{display:inline-flex;align-items:center;justify-content:center;gap:var(--space-2);padding:var(--space-3) var(--space-6);font-size:var(--text-base);font-weight:600;border-radius:var(--radius-xl);transition:all var(--transition-normal);position:relative;overflow:hidden}.btn:before{content:"";position:absolute;top:0;left:-100%;width:100%;height:100%;background:linear-gradient(90deg,transparent,rgba(255,255,255,.2),transparent);transition:left var(--transition-slow)}.btn:hover:before{left:100%}.btn-primary{background:var(--gradient-primary);color:#fff;box-shadow:0 4px 15px -3px var(--color-primary-glow)}.btn-primary:hover{transform:translateY(-2px);box-shadow:0 8px 25px -5px var(--color-primary-glow)}.btn-secondary{background:var(--glass-bg);color:var(--color-text-primary);border:1px solid var(--glass-border);-webkit-backdrop-filter:var(--glass-blur);backdrop-filter:var(--glass-blur)}.btn-secondary:hover{background:var(--glass-bg-light);border-color:var(--color-primary-light);transform:translateY(-2px)}.btn-accent{background:var(--gradient-accent);color:#fff;box-shadow:0 4px 15px -3px var(--color-accent-glow)}.btn-accent:hover{transform:translateY(-2px);box-shadow:0 8px 25px -5px var(--color-accent-glow)}.btn:focus-visible{outline:none;box-shadow:var(--focus-ring)}input,select,textarea{font-family:inherit;font-size:inherit;background:var(--glass-bg);border:1px solid var(--glass-border);border-radius:var(--radius-lg);padding:var(--space-3) var(--space-4);color:var(--color-text-primary);transition:all var(--transition-fast)}input:focus,select:focus,textarea:focus{outline:none;border-color:var(--color-primary-light);box-shadow:0 0 0 3px var(--color-primary-glow)}input::placeholder{color:var(--color-text-muted)}.container{width:100%;max-width:1200px;margin:0 auto;padding:0 var(--space-4)}.sr-only{position:absolute;width:1px;height:1px;padding:0;margin:-1px;overflow:hidden;clip:rect(0,0,0,0);white-space:nowrap;border:0}.glass{background:var(--glass-bg);backdrop-filter:var(--glass-blur);-webkit-backdrop-filter:var(--glass-blur);border:1px solid var(--glass-border);border-radius:var(--radius-2xl)}.glass-card{background:var(--glass-bg);backdrop-filter:var(--glass-blur);-webkit-backdrop-filter:var(--glass-blur);border:1px solid var(--glass-border);border-radius:var(--radius-2xl);padding:var(--space-6);transition:all var(--transition-normal)}.glass-card:hover{transform:translateY(-4px);box-shadow:var(--shadow-xl),var(--shadow-glow);border-color:var(--color-primary-light)}.gradient-text{background:var(--gradient-primary);-webkit-background-clip:text;-webkit-text-fill-color:transparent;background-clip:text}.gradient-text-accent{background:var(--gradient-accent);-webkit-background-clip:text;-webkit-text-fill-color:transparent;background-clip:text}@keyframes fadeIn{0%{opacity:0;transform:translateY(20px)}to{opacity:1;transform:translateY(0)}}@keyframes fadeInScale{0%{opacity:0;transform:scale(.95)}to{opacity:1;transform:scale(1)}}@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 pulse{0%,to{opacity:1}50%{opacity:.5}}@keyframes float{0%,to{transform:translateY(0)}50%{transform:translateY(-10px)}}@keyframes shimmer{0%{background-position:-200% 0}to{background-position:200% 0}}.animate-fadeIn{animation:fadeIn .6s ease-out forwards}.animate-fadeInScale{animation:fadeInScale .5s ease-out forwards}.animate-slideInLeft{animation:slideInLeft .5s ease-out forwards}.animate-slideInRight{animation:slideInRight .5s ease-out forwards}.animate-float{animation:float 3s ease-in-out infinite}.stagger-1{animation-delay:.1s}.stagger-2{animation-delay:.2s}.stagger-3{animation-delay:.3s}.stagger-4{animation-delay:.4s}.stagger-5{animation-delay:.5s}.math-display{font-family:var(--font-mono);font-size:var(--text-lg)}.fraction{display:inline-flex;flex-direction:column;align-items:center;vertical-align:middle;font-family:var(--font-mono);font-weight:600}.fraction .numerator,.fraction .denominator{padding:0 var(--space-2)}::-webkit-scrollbar{width:8px;height:8px}::-webkit-scrollbar-track{background:var(--color-bg-secondary);border-radius:var(--radius-full)}::-webkit-scrollbar-thumb{background:var(--color-bg-tertiary);border-radius:var(--radius-full)}::-webkit-scrollbar-thumb:hover{background:var(--color-primary-light)}@media(prefers-reduced-motion:reduce){*,*:before,*:after{animation-duration:.01ms!important;animation-iteration-count:1!important;transition-duration:.01ms!important}body:before{animation:none}}[dir=rtl]{--direction: rtl}[dir=rtl] .rtl-flip{transform:scaleX(-1)}@media(max-width:768px){h1{font-size:var(--text-4xl)}h2{font-size:var(--text-3xl)}h3{font-size:var(--text-2xl)}.glass-card{padding:var(--space-4)}}.navigation{display:flex;align-items:center;gap:var(--space-8)}.nav-list{display:flex;list-style:none;gap:var(--space-2);align-items:center}.nav-link{display:flex;align-items:center;gap:var(--space-2);padding:var(--space-2) var(--space-4);color:var(--color-text-secondary);font-weight:500;font-size:var(--text-sm);border-radius:var(--radius-lg);transition:all var(--transition-fast);position:relative;text-decoration:none;background:transparent;border:none;cursor:pointer;white-space:nowrap}.nav-link:after{display:none}.nav-link:hover{color:var(--color-text-primary);background:var(--glass-bg-light);text-decoration:none}.nav-link.active{color:var(--color-text-primary);background:var(--gradient-primary);box-shadow:0 4px 15px -3px var(--color-primary-glow)}.nav-link:focus-visible{outline:none;box-shadow:var(--focus-ring)}.nav-home{background:var(--glass-bg);border:1px solid var(--glass-border)}.nav-back{color:var(--color-text-muted);font-size:var(--text-xs)}.nav-back:hover{color:var(--color-primary)}.nav-dropdown{position:relative}.dropdown-toggle{display:flex;align-items:center;gap:var(--space-2)}.dropdown-toggle.open{background:var(--glass-bg-light);color:var(--color-text-primary)}.dropdown-menu{position:absolute;top:calc(100% + var(--space-2));left:0;min-width:220px;max-height:400px;overflow-y:auto;padding:var(--space-2);list-style:none;border-radius:var(--radius-xl);z-index:1000;animation:dropdownIn .2s ease-out;box-shadow:0 10px 40px -10px #0000004d,0 0 0 1px var(--glass-border)}@keyframes dropdownIn{0%{opacity:0;transform:translateY(-8px)}to{opacity:1;transform:translateY(0)}}.dropdown-item{display:flex;align-items:center;gap:var(--space-2);padding:var(--space-3) var(--space-4);color:var(--color-text-secondary);text-decoration:none;border-radius:var(--radius-lg);font-size:var(--text-sm);transition:all var(--transition-fast);cursor:pointer}.dropdown-item:hover{background:var(--glass-bg-light);color:var(--color-text-primary)}.dropdown-item.active{background:var(--gradient-primary);color:#fff}.dropdown-item.disabled{opacity:.5;cursor:not-allowed;pointer-events:none}.dropdown-item.disabled small{font-size:var(--text-xs);opacity:.7;margin-left:auto}.nav-separator{color:var(--color-text-muted);opacity:.3;padding:0 var(--space-1);font-weight:300;-webkit-user-select:none;user-select:none}.nav-section{flex-direction:column;gap:0;font-size:var(--text-xs)}.nav-link.disabled{opacity:.5;pointer-events:none;cursor:not-allowed;position:relative}.coming-soon-badge{font-size:.6rem;background:var(--color-warning);color:var(--color-dark);padding:.1rem .3rem;border-radius:var(--radius-sm);margin-left:var(--space-1);text-transform:uppercase;font-weight:600;letter-spacing:.05em}.language-selector{display:flex;gap:var(--space-1);padding:var(--space-1);background:var(--glass-bg);border-radius:var(--radius-xl);border:1px solid var(--glass-border)}.language-selector button{padding:var(--space-2) var(--space-3);font-size:var(--text-xs);font-weight:600;color:var(--color-text-muted);background:transparent;border:none;border-radius:var(--radius-lg);transition:all var(--transition-fast);cursor:pointer;text-transform:uppercase;letter-spacing:.05em}.language-selector button:hover{color:var(--color-text-primary);background:var(--glass-bg-light)}.language-selector button.active{color:#fff;background:var(--gradient-primary);box-shadow:0 2px 8px -2px var(--color-primary-glow)}.language-selector button:focus-visible{outline:none;box-shadow:var(--focus-ring)}@media(max-width:900px){.navigation{flex-direction:column;gap:var(--space-4)}.nav-list{flex-wrap:wrap;justify-content:center}.nav-link{padding:var(--space-2) var(--space-3);font-size:var(--text-xs)}.dropdown-menu{position:fixed;left:50%;transform:translate(-50%);top:auto;bottom:80px;max-width:90vw}@keyframes dropdownIn{0%{opacity:0;transform:translate(-50%) translateY(8px)}to{opacity:1;transform:translate(-50%) translateY(0)}}}@media(max-width:640px){.navigation{width:100%}.nav-list{width:100%;justify-content:space-around}.nav-link{padding:var(--space-2)}}.layout{min-height:100vh;display:flex;flex-direction:column;position:relative}.layout-header{position:sticky;top:0;z-index:100;background:#0f172acc;backdrop-filter:blur(20px);-webkit-backdrop-filter:blur(20px);border-bottom:1px solid var(--glass-border)}.header-content{display:flex;align-items:center;justify-content:space-between;padding:var(--space-4) var(--space-6);max-width:1400px;margin:0 auto;width:100%}.logo{display:flex;align-items:center;gap:var(--space-3);text-decoration:none}.logo-icon{font-size:var(--text-3xl);font-weight:800;background:var(--gradient-primary);-webkit-background-clip:text;-webkit-text-fill-color:transparent;background-clip:text;animation:float 3s ease-in-out infinite}.logo-text{font-size:var(--text-xl);font-weight:700;color:var(--color-text-primary);letter-spacing:-.02em}.layout-main{flex:1;padding:var(--space-8) 0;position:relative}.layout-main.immersive{padding:0}.layout-footer{background:#0f172ae6;-webkit-backdrop-filter:blur(10px);backdrop-filter:blur(10px);border-top:1px solid var(--glass-border);padding:var(--space-8) 0;margin-top:auto}.layout-footer .container{display:flex;justify-content:space-between;align-items:center;flex-wrap:wrap;gap:var(--space-4);max-width:1400px;padding:0 var(--space-6)}.layout-footer p{color:var(--color-text-muted);font-size:var(--text-sm);margin:0}.footer-nav{display:flex;gap:var(--space-6)}.footer-nav a{color:var(--color-text-secondary);font-size:var(--text-sm);font-weight:500;text-decoration:none;transition:all var(--transition-fast);position:relative}.footer-nav a:after{content:"";position:absolute;bottom:-4px;left:0;width:0;height:2px;background:var(--gradient-primary);transition:width var(--transition-fast)}.footer-nav a:hover{color:var(--color-text-primary)}.footer-nav a:hover:after{width:100%}@media(max-width:768px){.header-content{padding:var(--space-3) var(--space-4)}.logo-text{display:none}.layout-footer .container{flex-direction:column;text-align:center;padding:0 var(--space-4)}.footer-nav{gap:var(--space-4)}}.subject-card{display:flex;align-items:center;gap:var(--space-4);padding:var(--space-5);text-decoration:none;color:inherit;cursor:pointer;position:relative;overflow:hidden}.subject-card:before{content:"";position:absolute;top:0;left:-100%;width:100%;height:100%;background:linear-gradient(90deg,transparent,rgba(255,255,255,.1),transparent);transition:left var(--transition-slow)}.subject-card:hover:before{left:100%}.subject-card:hover{transform:translateY(-4px);box-shadow:var(--shadow-xl),var(--shadow-glow)}.subject-card.disabled{opacity:.6;cursor:not-allowed}.subject-card.disabled:hover{transform:none;box-shadow:none}.subject-card.disabled:before{display:none}.subject-card-icon{display:flex;align-items:center;justify-content:center;width:60px;height:60px;border-radius:var(--radius-xl);font-size:var(--text-2xl);flex-shrink:0;box-shadow:var(--shadow-md)}.subject-card-content{flex:1;min-width:0}.subject-card-title{font-size:var(--text-lg);font-weight:600;color:var(--color-text-primary);margin:0 0 var(--space-1) 0}.subject-card-description{font-size:var(--text-sm);color:var(--color-text-muted);margin:0;overflow:hidden;text-overflow:ellipsis;white-space:nowrap}.subject-card-badge{background:var(--color-warning);color:var(--color-bg-primary);font-size:var(--text-xs);font-weight:600;padding:var(--space-1) var(--space-3);border-radius:var(--radius-full);text-transform:uppercase;letter-spacing:.05em}.subject-card-arrow{font-size:var(--text-xl);color:var(--color-text-muted);transition:transform var(--transition-fast),color var(--transition-fast)}.subject-card:hover .subject-card-arrow{transform:translate(4px);color:var(--color-primary-light)}@media(max-width:768px){.subject-card{padding:var(--space-4)}.subject-card-icon{width:50px;height:50px;font-size:var(--text-xl)}.subject-card-title{font-size:var(--text-base)}}.subjects-page{padding:var(--space-8) 0;min-height:calc(100vh - 200px)}.subjects-header{text-align:center;margin-bottom:var(--space-12);animation:fadeIn .6s ease-out}.subjects-header h1{font-size:var(--text-5xl);margin-bottom:var(--space-4);background:var(--gradient-primary);-webkit-background-clip:text;-webkit-text-fill-color:transparent;background-clip:text}.subjects-subtitle{font-size:var(--text-xl);color:var(--color-text-secondary);max-width:600px;margin:0 auto}.subjects-grid{display:grid;grid-template-columns:repeat(auto-fit,minmax(300px,1fr));gap:var(--space-6);max-width:800px;margin:0 auto var(--space-12)}.subjects-grid>*{animation:fadeIn .6s ease-out;animation-fill-mode:both}.subjects-grid>*:nth-child(1){animation-delay:.1s}.subjects-grid>*:nth-child(2){animation-delay:.2s}.subjects-info{max-width:800px;margin:0 auto;padding:var(--space-8);text-align:center;animation:fadeIn .6s ease-out .3s;animation-fill-mode:both}.subjects-info h2{font-size:var(--text-2xl);margin-bottom:var(--space-4);color:var(--color-text-primary)}.subjects-info p{font-size:var(--text-base);color:var(--color-text-secondary);line-height:var(--line-height-relaxed);margin:0}@media(max-width:768px){.subjects-header h1{font-size:var(--text-4xl)}.subjects-subtitle{font-size:var(--text-lg)}.subjects-grid{grid-template-columns:1fr}.subjects-info{padding:var(--space-6)}}.courses-page{padding:var(--space-8) 0;min-height:calc(100vh - 200px)}.courses-header{text-align:center;margin-bottom:var(--space-10);animation:fadeIn .6s ease-out}.courses-breadcrumb{margin-bottom:var(--space-4)}.courses-breadcrumb a{font-size:var(--text-sm);color:var(--color-text-muted);text-decoration:none;display:inline-flex;align-items:center;gap:var(--space-2)}.courses-breadcrumb a:before{content:"←"}.courses-breadcrumb a:hover{color:var(--color-primary-light)}.courses-header h1{font-size:var(--text-4xl);margin-bottom:var(--space-3);background:var(--gradient-primary);-webkit-background-clip:text;-webkit-text-fill-color:transparent;background-clip:text}.courses-subtitle{font-size:var(--text-lg);color:var(--color-text-secondary);max-width:600px;margin:0 auto}.courses-grid{display:grid;grid-template-columns:repeat(auto-fill,minmax(320px,1fr));gap:var(--space-4);max-width:1000px;margin:0 auto}.course-item{animation:fadeIn .6s ease-out;animation-fill-mode:both}@media(max-width:768px){.courses-header h1{font-size:var(--text-3xl)}.courses-subtitle{font-size:var(--text-base)}.courses-grid{grid-template-columns:1fr}}.topics-page{padding:var(--space-8) 0;min-height:calc(100vh - 200px)}.topics-header{text-align:center;margin-bottom:var(--space-10);animation:fadeIn .6s ease-out}.topics-breadcrumb{margin-bottom:var(--space-4);display:flex;align-items:center;justify-content:center;gap:var(--space-2);flex-wrap:wrap}.topics-breadcrumb a{font-size:var(--text-sm);color:var(--color-text-muted);text-decoration:none}.topics-breadcrumb a:hover{color:var(--color-primary-light)}.topics-breadcrumb .separator{color:var(--color-text-muted);font-size:var(--text-sm)}.topics-header h1{font-size:var(--text-4xl);margin-bottom:var(--space-3);color:var(--course-color, var(--color-primary))}.topics-subtitle{font-size:var(--text-lg);color:var(--color-text-secondary);max-width:600px;margin:0 auto}.topics-grid{display:grid;grid-template-columns:repeat(auto-fill,minmax(300px,1fr));gap:var(--space-4);max-width:1000px;margin:0 auto}.topic-item{animation:fadeIn .6s ease-out;animation-fill-mode:both}@media(max-width:768px){.topics-header h1{font-size:var(--text-3xl)}.topics-subtitle{font-size:var(--text-base)}.topics-grid{grid-template-columns:1fr}}.accessibility-page{padding:var(--space-8) 0}.page-header{text-align:center;margin-bottom:var(--space-10)}.page-header h1{margin-bottom:var(--space-4)}.page-description{font-size:var(--text-lg);color:var(--color-text-secondary);max-width:700px;margin:0 auto}.dua-section,.wcag-section,.multilingual-section,.keyboard-section,.contact-section{padding:var(--space-8);border-radius:var(--radius-xl);margin-bottom:var(--space-6)}.dua-section h2,.wcag-section h2,.multilingual-section h2,.keyboard-section h2,.contact-section h2{margin-bottom:var(--space-4);color:var(--color-text-primary)}.dua-section>p,.wcag-section>p,.multilingual-section>p,.contact-section>p{color:var(--color-text-secondary);margin-bottom:var(--space-6);line-height:var(--line-height-relaxed)}.dua-principles{display:grid;grid-template-columns:repeat(auto-fit,minmax(280px,1fr));gap:var(--space-6);margin-top:var(--space-6)}.principle-card{padding:var(--space-6);background:var(--color-bg-primary);border-radius:var(--radius-lg);border:1px solid var(--color-border)}.principle-icon{font-size:2.5rem;margin-bottom:var(--space-3)}.principle-card h3{margin-bottom:var(--space-3);color:var(--color-primary)}.principle-card ul{list-style:none;padding:0}.principle-card li{padding:var(--space-2) 0;padding-left:var(--space-5);position:relative;color:var(--color-text-secondary);font-size:var(--text-sm)}.principle-card li:before{content:"•";position:absolute;left:var(--space-2);color:var(--color-primary);font-weight:700}.wcag-checklist{display:flex;flex-direction:column;gap:var(--space-3)}.checklist-item{display:flex;align-items:flex-start;gap:var(--space-3);padding:var(--space-4);background:var(--color-bg-primary);border-radius:var(--radius-lg)}.check-icon{color:var(--color-success);font-weight:700;flex-shrink:0}.feature-list{list-style:none;padding:0;display:grid;gap:var(--space-3)}.feature-list li{padding:var(--space-3) var(--space-4);background:var(--color-bg-primary);border-radius:var(--radius-lg);border-left:4px solid var(--color-primary)}.keyboard-table{width:100%;border-collapse:collapse;margin-top:var(--space-4);background:var(--color-bg-primary);border-radius:var(--radius-lg);overflow:hidden}.keyboard-table th,.keyboard-table td{padding:var(--space-3) var(--space-4);text-align:left;border-bottom:1px solid var(--color-border)}.keyboard-table th{background:var(--color-bg-tertiary);font-weight:600;color:var(--color-text-primary)}.keyboard-table td{color:var(--color-text-secondary)}.keyboard-table tr:last-child td{border-bottom:none}kbd{display:inline-block;padding:var(--space-1) var(--space-2);font-family:var(--font-mono);font-size:var(--text-sm);background:var(--color-bg-tertiary);border:1px solid var(--color-border);border-radius:var(--radius-sm);box-shadow:0 2px 0 var(--color-border)}@media(max-width:640px){.dua-section,.wcag-section,.multilingual-section,.keyboard-section,.contact-section{padding:var(--space-4)}.keyboard-table{font-size:var(--text-sm)}.keyboard-table th,.keyboard-table td{padding:var(--space-2)}}