:root,html[data-theme=dark]{--bg: #0b1220;--surface: #111827;--surface-elevated: #1a2332;--surface-muted: #151e2e;--border: #1e2d45;--text: #f1f5f9;--text-muted: #94a3b8;--text-subtle: #64748b;--accent: #3b82f6;--accent-dark: #2563eb;--accent-end: #1d4ed8;--accent-soft: rgba(59, 130, 246, .12);--danger: #f87171;--shadow-glow: 0 4px 24px rgba(59, 130, 246, .08);--header-bg: rgba(11, 18, 32, .92);--nav-hover-bg: rgba(59, 130, 246, .12);--hero-glow-1: rgba(59, 130, 246, .15);--hero-glow-2: rgba(29, 78, 216, .1);--hero-badge-border: rgba(59, 130, 246, .25);--hero-title-gradient: linear-gradient(135deg, #fff 30%, #93c5fd);--code-bg: #0b1220;--code-text: #e2e8f0;--success-bg: rgba(34, 197, 94, .1);--success-text: #4ade80;--radius-sm: .375rem;--radius-md: .5rem;--radius-lg: .75rem;--font-mono: ui-monospace, SFMono-Regular, Menlo, Monaco, Consolas, monospace}html[data-theme=light]{--bg: #f8fafc;--surface: #ffffff;--surface-elevated: #ffffff;--surface-muted: #f1f5f9;--border: #e2e8f0;--text: #0f172a;--text-muted: #64748b;--text-subtle: #94a3b8;--accent: #2563eb;--accent-dark: #1d4ed8;--accent-end: #1e40af;--accent-soft: rgba(37, 99, 235, .1);--danger: #dc2626;--shadow-glow: 0 4px 24px rgba(37, 99, 235, .08);--header-bg: rgba(255, 255, 255, .92);--nav-hover-bg: rgba(37, 99, 235, .08);--hero-glow-1: rgba(37, 99, 235, .12);--hero-glow-2: rgba(29, 78, 216, .08);--hero-badge-border: rgba(37, 99, 235, .2);--hero-title-gradient: linear-gradient(135deg, #0f172a 30%, #2563eb);--code-bg: #1e293b;--code-text: #e2e8f0;--success-bg: rgba(22, 163, 74, .1);--success-text: #16a34a}*,*:before,*:after{box-sizing:border-box}html{-webkit-text-size-adjust:100%}body{margin:0;font-family:Segoe UI,system-ui,-apple-system,BlinkMacSystemFont,Roboto,sans-serif;font-size:16px;line-height:1.5;color:var(--text);background:var(--bg)}html[dir=rtl] body{font-family:Vazirmatn,Segoe UI,Tahoma,sans-serif}html[dir=rtl] .back-link,html[dir=rtl] .category-filter,html[dir=rtl] .saved-item,html[dir=rtl] .lesson-card__footer,html[dir=rtl] .section__header,html[dir=rtl] .header__inner,html[dir=rtl] .header__nav,html[dir=rtl] .admin-table th,html[dir=rtl] .admin-table td,html[dir=rtl] .categories-sidebar h2,html[dir=rtl] .section__header h2{text-align:right}html[dir=rtl] .content-renderer ul{padding-right:1.25rem;padding-left:0}@media(max-width:768px){html[dir=rtl] .header__nav a,html[dir=rtl] .header__nav button{text-align:right}}h1,h2,h3,h4,p{margin:0}a{color:inherit}.container{width:100%;max-width:72rem;margin:0 auto;padding:0 1rem}@media(min-width:640px){.container{padding:0 1.5rem}}.page-header{padding:2.5rem 0 1.5rem;background:var(--surface);border-bottom:1px solid var(--border)}.page-header h1{font-size:clamp(1.75rem,3vw,2.25rem);margin-bottom:.5rem}.page-header p{color:var(--text-muted);font-size:1.0625rem;max-width:36rem}.section{padding:2.5rem 0}.section--alt{background:var(--surface)}.section__header{display:flex;justify-content:space-between;align-items:flex-end;gap:1rem;margin-bottom:1.5rem;flex-wrap:wrap}.section__header h2{font-size:1.5rem}.section__header p{color:var(--text-muted);margin-top:.25rem}.section__link{color:var(--accent);text-decoration:none;font-weight:500;font-size:.9375rem}.section__link:hover{text-decoration:underline}.grid{display:grid;gap:1.25rem}.grid--2{grid-template-columns:1fr}@media(min-width:768px){.grid--2{grid-template-columns:repeat(2,1fr)}}.grid--3{grid-template-columns:1fr}@media(min-width:640px){.grid--3{grid-template-columns:repeat(2,1fr)}}@media(min-width:1024px){.grid--3{grid-template-columns:repeat(3,1fr)}}.btn{display:inline-flex;align-items:center;gap:.5rem;padding:.625rem 1.25rem;border-radius:var(--radius-sm);font-size:.9375rem;font-weight:500;text-decoration:none;border:1px solid transparent;cursor:pointer;font-family:inherit;transition:background .2s,color .2s,border-color .2s}.btn:disabled{opacity:.6;cursor:not-allowed}.btn--primary{background:var(--accent);color:#fff}.btn--primary:hover:not(:disabled){background:var(--accent-dark)}.btn--secondary{background:transparent;color:var(--text);border-color:var(--border)}.btn--secondary:hover:not(:disabled){background:var(--surface-muted)}.empty-state{padding:4rem 1rem;text-align:center;color:var(--text-muted)}.empty-state h1{margin-bottom:.5rem;color:var(--text)}.empty-state p{margin-bottom:1.5rem}.empty-message{color:var(--text-muted);grid-column:1/-1}