:root{--primary: #2563eb;--primary-hover: #1d4ed8;--accent: #0ea5a8;--accent-hover: #0c8c8f;--bg: #f7f8fb;--card: #ffffff;--surface: #f9fafb;--text: #0b1220;--muted: #6b7280;--border: #e5e7eb;--success: #16a34a;--warning: #f59e0b;--danger: #dc2626;--info: #0891b2;--primary-color: var(--primary);--primary-hover: var(--primary-hover);--primary-color-alpha: rgba(37, 99, 235, .1);--sidebar-bg: #f8fafc;--content-bg: var(--card);--chat-bg: #f8fafc;--input-bg: #ffffff;--hover-bg: #f1f5f9;--active-bg: #e2e8f0;--placeholder-bg: #f8fafc;--code-bg: #1e1e1e;--code-header-bg: #2d2d2d;--code-text: #d4d4d4;--user-message-bg: var(--primary);--user-message-text: #ffffff;--assistant-message-bg: #f1f5f9;--assistant-message-text: #374151;--system-message-bg: #fef3c7;--system-message-text: #92400e;--text-primary: var(--text);--text-secondary: var(--muted);--text-tertiary: #9ca3af;--scrollbar-thumb: #d1d5db;--scrollbar-thumb-hover: #9ca3af;--radius-sm: 6px;--radius-md: 10px;--radius-lg: 14px;--shadow-sm: 0 1px 3px rgba(0,0,0,.08);--shadow-md: 0 6px 20px rgba(2,6,23,.06);--shadow-lg: 0 20px 40px rgba(2,6,23,.08);--sidebar-width: 280px;--chat-width: 360px;--content-padding: 2rem}@media (prefers-color-scheme: dark){:root{--bg: #0b1220;--card: #0f172a;--surface: #0b1220;--text: #e5e7eb;--muted: #a3a3a3;--border: #334155;--primary: #3b82f6;--primary-hover: #2563eb;--accent: #22d3ee;--accent-hover: #06b6d4;--primary-color: var(--primary);--primary-hover: var(--primary-hover);--primary-color-alpha: rgba(59, 130, 246, .1);--sidebar-bg: #1f2937;--content-bg: #111827;--chat-bg: #1f2937;--input-bg: #374151;--hover-bg: #374151;--active-bg: #4b5563;--placeholder-bg: #1f2937;--code-bg: #0d1117;--code-header-bg: #21262d;--code-text: #e6edf3;--user-message-bg: var(--primary);--user-message-text: #ffffff;--assistant-message-bg: #374151;--assistant-message-text: #f9fafb;--system-message-bg: #451a03;--system-message-text: #fbbf24;--text-primary: var(--text);--text-secondary: var(--muted);--text-tertiary: #9ca3af;--scrollbar-thumb: #4b5563;--scrollbar-thumb-hover: #6b7280}}@media (min-width: 640px){:root{--content-padding: 1.5rem}}@media (min-width: 768px){:root{--content-padding: 2rem}}@media (max-width: 1200px){:root{--sidebar-width: 250px;--chat-width: 320px}}@media (max-width: 1024px){:root{--sidebar-width: 220px;--chat-width: 300px;--content-padding: 1.5rem}}@media (max-width: 768px){:root{--content-padding: 1rem}}@media (pointer: coarse){button,a,input[type=button],input[type=submit],input[type=checkbox],input[type=radio]{min-height:44px;min-width:44px}}.lesson-page{display:grid;grid-template-columns:var(--sidebar-width) 1fr var(--chat-width);grid-template-areas:"sidebar content chat";height:100vh;overflow:hidden;font-family:-apple-system,BlinkMacSystemFont,Segoe UI,Roboto,Oxygen,Ubuntu,Cantarell,sans-serif;background-color:var(--content-bg)}.lesson-sidebar{grid-area:sidebar;overflow:hidden}.lesson-content{grid-area:content;overflow-y:auto}.chat-panel{grid-area:chat;overflow:hidden}@media (max-width: 1200px){.lesson-page{grid-template-columns:250px 1fr 320px}:root{--sidebar-width: 250px;--chat-width: 320px}}@media (max-width: 1024px){.lesson-page{grid-template-columns:220px 1fr 300px}:root{--sidebar-width: 220px;--chat-width: 300px;--content-padding: 1.5rem}}@media (max-width: 768px){.lesson-page{grid-template-columns:1fr;grid-template-rows:auto 1fr auto;grid-template-areas:"sidebar" "content" "chat"}.lesson-sidebar{max-height:200px;overflow-y:auto}.chat-panel{max-height:300px}:root{--content-padding: 1rem}}*:focus-visible{outline:2px solid var(--primary-color);outline-offset:2px}::selection{background-color:var(--primary-color-alpha);color:var(--text-primary)}*{scroll-behavior:smooth}*{box-sizing:border-box}body{margin:0;padding:0;font-family:inherit;background-color:var(--content-bg);color:var(--text-primary);-webkit-font-smoothing:antialiased;-moz-osx-font-smoothing:grayscale}button{font-family:inherit;font-size:inherit}a{color:var(--primary-color);text-decoration:none}a:hover{text-decoration:underline}a:focus-visible{outline:2px solid var(--primary-color);outline-offset:2px;text-decoration:none}@keyframes pulse{0%,to{opacity:1}50%{opacity:.5}}.animate-pulse{animation:pulse 2s cubic-bezier(.4,0,.6,1) infinite}.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}.navbar.svelte-1iqxfzn{background:var(--card);border-bottom:1px solid var(--border);position:sticky;top:0;z-index:100;box-shadow:0 1px 3px #0000001a}.nav-container.svelte-1iqxfzn{max-width:1200px;margin:0 auto;padding:0 1rem;display:flex;align-items:center;justify-content:space-between;height:4rem}.nav-brand.svelte-1iqxfzn .brand-title:where(.svelte-1iqxfzn){font-size:1.5rem;font-weight:700;margin:0;color:var(--accent);letter-spacing:-.01em;background:none;border:none;cursor:pointer;padding:.25rem .5rem;border-radius:8px;transition:all .15s ease}.nav-brand.svelte-1iqxfzn .brand-title:where(.svelte-1iqxfzn):hover{background:var(--bg);transform:translateY(-1px)}.nav-menu.svelte-1iqxfzn{display:flex;gap:2rem;align-items:center}.nav-dropdown.svelte-1iqxfzn{position:relative}.nav-link.svelte-1iqxfzn{background:none;border:none;color:var(--text);font-size:1rem;font-weight:500;padding:.5rem 1rem;border-radius:8px;cursor:pointer;transition:all .15s ease;position:relative;display:flex;align-items:center;gap:.5rem}.nav-link.svelte-1iqxfzn:hover{background:var(--bg);color:var(--accent)}.nav-link.active.svelte-1iqxfzn{color:var(--accent);font-weight:600}.nav-link.active.svelte-1iqxfzn:after{content:"";position:absolute;bottom:-1px;left:50%;transform:translate(-50%);width:20px;height:2px;background:var(--accent);border-radius:1px}.dropdown-arrow.svelte-1iqxfzn{width:12px;height:12px;opacity:.7;transition:transform .2s ease}.dropdown-arrow.open.svelte-1iqxfzn{transform:rotate(180deg)}.dropdown-menu.svelte-1iqxfzn{position:absolute;top:calc(100% + .5rem);left:0;background:var(--card);border:1px solid var(--border);border-radius:8px;box-shadow:0 4px 12px #0000001a;min-width:180px;padding:.5rem;z-index:1000;animation:svelte-1iqxfzn-slideDown .2s ease}@keyframes svelte-1iqxfzn-slideDown{0%{opacity:0;transform:translateY(-10px)}to{opacity:1;transform:translateY(0)}}.dropdown-item.svelte-1iqxfzn{width:100%;background:none;border:none;color:var(--text);font-size:.95rem;font-weight:500;padding:.75rem 1rem;border-radius:6px;cursor:pointer;transition:all .15s ease;text-align:left;display:block}.dropdown-item.svelte-1iqxfzn:hover{background:var(--bg);color:var(--accent)}.dropdown-item.active.svelte-1iqxfzn{color:var(--accent);font-weight:600;background:var(--bg)}.external-icon.svelte-1iqxfzn{width:12px;height:12px;margin-left:.25rem;opacity:.7;transition:opacity .15s ease}.nav-link.external.svelte-1iqxfzn:hover .external-icon:where(.svelte-1iqxfzn){opacity:1}.nav-auth.svelte-1iqxfzn{display:flex;align-items:center;gap:1rem}.auth-loading.svelte-1iqxfzn{color:var(--muted);font-size:.9rem}.user-menu.svelte-1iqxfzn{display:flex;align-items:center;gap:.75rem}.user-avatar.svelte-1iqxfzn{width:32px;height:32px;border-radius:50%;border:2px solid var(--border)}.user-name.svelte-1iqxfzn{color:var(--text);font-size:.9rem;font-weight:500;max-width:150px;overflow:hidden;text-overflow:ellipsis;white-space:nowrap}.login-btn.svelte-1iqxfzn,.logout-btn.svelte-1iqxfzn{background:var(--accent);color:#fff;border:none;padding:.5rem 1rem;border-radius:8px;font-size:.9rem;font-weight:500;cursor:pointer;transition:all .15s ease}.login-btn.svelte-1iqxfzn:hover,.logout-btn.svelte-1iqxfzn:hover{background:var(--accent-hover);transform:translateY(-1px)}.logout-btn.svelte-1iqxfzn{background:transparent;color:var(--muted);border:1px solid var(--border);padding:.4rem .8rem}.logout-btn.svelte-1iqxfzn:hover{background:var(--bg);color:var(--text)}.nav-mobile-toggle.svelte-1iqxfzn{display:none}@media (max-width: 768px){.nav-container.svelte-1iqxfzn{flex-wrap:wrap;gap:0;min-height:4rem}.nav-menu.svelte-1iqxfzn{display:none;width:100%;order:2;flex-direction:column;gap:0;padding:1rem 0;border-top:1px solid var(--border);max-height:0;overflow:hidden;opacity:0;transition:max-height .3s ease,opacity .3s ease,padding .3s ease}.nav-menu.open.svelte-1iqxfzn{display:flex;max-height:500px;opacity:1}.nav-menu.svelte-1iqxfzn .nav-link:where(.svelte-1iqxfzn){width:100%;padding:.75rem 1rem;justify-content:flex-start;border-radius:0;border-bottom:1px solid var(--border)}.nav-menu.svelte-1iqxfzn .nav-link:where(.svelte-1iqxfzn):last-child{border-bottom:none}.nav-dropdown.svelte-1iqxfzn{width:100%}.nav-dropdown.svelte-1iqxfzn .dropdown-toggle:where(.svelte-1iqxfzn){width:100%;justify-content:space-between}.nav-dropdown.svelte-1iqxfzn .dropdown-menu:where(.svelte-1iqxfzn){position:static;width:100%;margin-top:0;border:none;border-top:1px solid var(--border);border-radius:0;box-shadow:none;animation:none}.nav-auth.svelte-1iqxfzn{order:3;width:100%;justify-content:center;margin-top:0;padding:1rem 0;border-top:1px solid var(--border);display:none}.nav-menu.open.svelte-1iqxfzn~.nav-auth:where(.svelte-1iqxfzn){display:flex}.user-menu.svelte-1iqxfzn{flex-direction:column;gap:.5rem;text-align:center;width:100%}.user-name.svelte-1iqxfzn{max-width:none}.nav-mobile-toggle.svelte-1iqxfzn{display:block;order:1}.mobile-menu-btn.svelte-1iqxfzn{background:none;border:none;cursor:pointer;padding:.5rem;display:flex;flex-direction:column;gap:4px;min-width:44px;min-height:44px;align-items:center;justify-content:center;transition:all .3s ease}.mobile-menu-btn.svelte-1iqxfzn span:where(.svelte-1iqxfzn){width:24px;height:2px;background:var(--text);transition:all .3s ease;border-radius:2px}.mobile-menu-btn.open.svelte-1iqxfzn span:where(.svelte-1iqxfzn):nth-child(1){transform:rotate(45deg) translate(6px,6px)}.mobile-menu-btn.open.svelte-1iqxfzn span:where(.svelte-1iqxfzn):nth-child(2){opacity:0}.mobile-menu-btn.open.svelte-1iqxfzn span:where(.svelte-1iqxfzn):nth-child(3){transform:rotate(-45deg) translate(6px,-6px)}.mobile-menu-btn.svelte-1iqxfzn:hover{background:var(--bg)}}.footer.svelte-bw6mw2{background:var(--card);border-top:1px solid var(--border);margin-top:4rem;padding:3rem 2rem 1.5rem}.footer-content.svelte-bw6mw2{max-width:1200px;margin:0 auto;display:grid;grid-template-columns:repeat(auto-fit,minmax(250px,1fr));gap:2rem;margin-bottom:2rem}.footer-section.svelte-bw6mw2 h3:where(.svelte-bw6mw2){font-size:1.25rem;font-weight:700;color:var(--text);margin:0 0 .75rem}.footer-section.svelte-bw6mw2 h4:where(.svelte-bw6mw2){font-size:1rem;font-weight:600;color:var(--text);margin:0 0 1rem}.footer-section.svelte-bw6mw2 p:where(.svelte-bw6mw2){color:var(--muted);font-size:.9rem;line-height:1.6;margin:0}.footer-links.svelte-bw6mw2{display:flex;flex-direction:column;gap:.75rem}.footer-links.svelte-bw6mw2 a:where(.svelte-bw6mw2){color:var(--muted);text-decoration:none;font-size:.9rem;transition:color .2s ease}.footer-links.svelte-bw6mw2 a:where(.svelte-bw6mw2):hover{color:var(--accent);text-decoration:underline}.footer-bottom.svelte-bw6mw2{max-width:1200px;margin:0 auto;padding-top:2rem;border-top:1px solid var(--border);text-align:center}.footer-bottom.svelte-bw6mw2 p:where(.svelte-bw6mw2){color:var(--muted);font-size:.875rem;margin:0}@media (max-width: 768px){.footer.svelte-bw6mw2{padding:2rem 1rem 1rem}.footer-content.svelte-bw6mw2{grid-template-columns:1fr;gap:1.5rem}.footer-links.svelte-bw6mw2{gap:.5rem}}html{font-family:-apple-system,system-ui,Segoe UI,Roboto,Helvetica,Arial,"Apple Color Emoji","Segoe UI Emoji"}.app.svelte-102iby0{min-height:100vh;background:var(--bg);color:var(--text)}.main-content.svelte-102iby0{min-height:calc(100vh - 4rem)}@media (max-width: 768px){.main-content.svelte-102iby0{min-height:calc(100vh - 4rem)}}