:root{--font-primary: "Sora", -apple-system, BlinkMacSystemFont, sans-serif;--font-mono: "JetBrains Mono", monospace;--primary: #00d4ff;--primary-dark: #00a8cc;--accent: #7c3aed;--accent-light: #a78bfa;--bg-primary: #0a0a0f;--bg-secondary: #12121a;--bg-tertiary: #1a1a24;--bg-card: #1e1e2a;--text-primary: #f0f0f5;--text-secondary: #9090a0;--text-muted: #606070;--border: #2a2a3a;--border-light: #3a3a4a;--success: #10b981;--error: #ef4444;--warning: #f59e0b;--shadow: 0 4px 20px rgba(0, 0, 0, .4);--shadow-lg: 0 8px 40px rgba(0, 0, 0, .6);--radius: 12px;--radius-lg: 20px}[data-theme=light]{--bg-primary: #f5f7fa;--bg-secondary: #ffffff;--bg-tertiary: #eef1f5;--bg-card: #ffffff;--text-primary: #1a1a2e;--text-secondary: #4a4a5a;--text-muted: #8a8a9a;--border: #e0e4ea;--border-light: #d0d4da;--shadow: 0 4px 20px rgba(0, 0, 0, .08);--shadow-lg: 0 8px 40px rgba(0, 0, 0, .12)}*{margin:0;padding:0;box-sizing:border-box}html,body{height:100%}body{font-family:var(--font-primary);background:var(--bg-primary);color:var(--text-primary);line-height:1.6}#root{height:100%}.loading-screen{height:100vh;display:flex;flex-direction:column;align-items:center;justify-content:center;gap:20px;background:var(--bg-primary)}.loading-spinner{width:48px;height:48px;border:3px solid var(--border);border-top-color:var(--primary);border-radius:50%;animation:spin 1s linear infinite}@keyframes spin{to{transform:rotate(360deg)}}.auth-page{min-height:100vh;display:flex;align-items:center;justify-content:center;padding:20px;background:radial-gradient(ellipse at 20% 80%,rgba(0,212,255,.08) 0%,transparent 50%),radial-gradient(ellipse at 80% 20%,rgba(124,58,237,.08) 0%,transparent 50%),var(--bg-primary)}.auth-container{width:100%;max-width:420px;background:var(--bg-secondary);border:1px solid var(--border);border-radius:var(--radius-lg);padding:40px;box-shadow:var(--shadow-lg)}.auth-container.class-selection{max-width:520px}.auth-header{text-align:center;margin-bottom:32px}.logo{font-size:56px;margin-bottom:16px;filter:drop-shadow(0 4px 12px rgba(0,212,255,.3))}.auth-header h1{font-size:28px;font-weight:700;background:linear-gradient(135deg,var(--primary),var(--accent));-webkit-background-clip:text;-webkit-text-fill-color:transparent;background-clip:text;margin-bottom:8px}.auth-header p{color:var(--text-secondary);font-size:15px}.auth-form{display:flex;flex-direction:column;gap:20px}.input-group{display:flex;flex-direction:column;gap:8px}.input-group label{font-size:14px;font-weight:500;color:var(--text-secondary)}.input-group input{padding:14px 16px;background:var(--bg-tertiary);border:1px solid var(--border);border-radius:var(--radius);color:var(--text-primary);font-size:15px;font-family:inherit;transition:all .2s}.input-group 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h1{font-size:20px;font-weight:700;background:linear-gradient(135deg,var(--primary),var(--accent));-webkit-background-clip:text;-webkit-text-fill-color:transparent;background-clip:text}.api-key-notice{background:linear-gradient(135deg,#f59e0b26,#7c3aed26);border:1px solid var(--warning);color:var(--warning);padding:12px 20px;text-align:center;font-size:14px;font-weight:500;animation:slideDown .3s ease-out,fadeOut .5s ease-out 4.5s forwards}@keyframes slideDown{0%{transform:translateY(-100%);opacity:0}to{transform:translateY(0);opacity:1}}@keyframes fadeOut{0%{opacity:1}to{opacity:0}}.messages-container{flex:1;overflow-y:auto;padding:24px}.welcome-screen{height:100%;display:flex;flex-direction:column;align-items:center;justify-content:center;text-align:center}.welcome-icon{font-size:80px;margin-bottom:24px;filter:drop-shadow(0 8px 24px rgba(0,212,255,.3))}.welcome-screen h2{font-size:28px;font-weight:700;margin-bottom:12px}.welcome-screen 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