:root{--bg-primary: #0a0f1a;--bg-secondary: #1a1a2e;--bg-card: rgba(255, 255, 255, .05);--border-color: rgba(255, 255, 255, .1);--text-primary: #fff;--text-secondary: rgba(255, 255, 255, .7);--text-muted: rgba(255, 255, 255, .6);--accent: #00ff9d;--accent-hover: #00cc7d;--error: #ff6b6b;--warning: #ffc800;--radius: 10px;--radius-sm: 6px}*{margin:0;padding:0;box-sizing:border-box}body{font-family:system-ui,-apple-system,sans-serif;background:linear-gradient(180deg,var(--bg-primary) 0%,var(--bg-secondary) 100%);min-height:100vh;color:var(--text-primary);padding:0;line-height:1.6}.container{max-width:800px;margin:0 auto}h1{font-size:1.8rem;margin-bottom:5px;display:flex;align-items:center;gap:10px}h1 span{color:var(--warning)}h2{font-size:1.3rem;margin-bottom:15px;display:flex;align-items:center;gap:10px}.subtitle{color:var(--text-muted);margin-bottom:20px;font-size:.9rem}.card{background:var(--bg-card);border:1px solid var(--border-color);border-radius:var(--radius);padding:30px;margin-bottom:20px}.card p{color:var(--text-secondary);margin-bottom:20px}input,textarea,select{width:100%;padding:12px 16px;border:1px solid var(--border-color);border-radius:var(--radius-sm);background:#ffffff0d;color:var(--text-primary);font-size:1rem;margin-bottom:15px}input:focus,textarea:focus,select:focus{outline:none;border-color:var(--accent)}input::placeholder,textarea::placeholder{color:var(--text-muted)}button{padding:12px 24px;background:linear-gradient(135deg,var(--accent) 0%,var(--accent-hover) 100%);color:#000;font-weight:600;border:none;border-radius:var(--radius-sm);cursor:pointer;font-size:1rem;transition:transform .2s}button:hover{transform:scale(1.02)}button:disabled{opacity:.5;cursor:not-allowed;transform:none}.btn-secondary{background:transparent;border:1px solid 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a:hover{text-decoration:underline}.error-text{color:var(--error);font-size:.9rem;margin-top:5px}.text-center{text-align:center}.mb-20{margin-bottom:20px}.mt-20{margin-top:20px}.user-menu-container{position:relative}.btn-user-menu{display:flex;align-items:center;gap:8px;padding:8px 16px;background:#ffffff1a;border:1px solid var(--border-color);border-radius:24px;color:var(--text-primary);cursor:pointer;font-size:.9rem;transition:all .2s}.btn-user-menu:hover{background:#ffffff26;border-color:var(--accent)}.btn-user-menu .dropdown-arrow{font-size:.6rem;color:var(--text-muted)}.btn-connect-header{padding:8px 16px;background:transparent;border:1px solid var(--accent);border-radius:24px;color:var(--accent);cursor:pointer;font-size:.9rem;font-weight:600;transition:all .2s}.btn-connect-header:hover{background:var(--accent);color:#000}.user-menu-dropdown{position:absolute;top:calc(100% + 8px);right:0;min-width:220px;background:var(--bg-secondary);border:1px solid var(--border-color);border-radius:12px;box-shadow:0 8px 32px #0006;z-index:1000;overflow:hidden}.user-menu-login{position:absolute;top:calc(100% + 8px);right:0;min-width:280px;background:var(--bg-secondary);border:1px solid var(--border-color);border-radius:12px;box-shadow:0 8px 32px #0006;z-index:1000}.dropdown-item{display:block;padding:12px 16px;color:var(--text-primary);text-decoration:none;font-size:.9rem;transition:background .2s}.dropdown-item:hover{background:#ffffff1a}.zap-button-container{padding:15px;background:#ffffff0d;border-radius:var(--radius)}.zap-warning{display:flex;align-items:center;gap:8px;padding:10px;background:#ffc8001a;border-radius:var(--radius-sm);margin-bottom:15px;font-size:.9rem}.zap-warning a{color:var(--warning)}.zap-amounts{display:flex;flex-wrap:wrap;gap:10px}.zap-amount-btn{padding:10px 16px;background:#00ff9d1a;border:1px solid var(--accent);border-radius:var(--radius-sm);color:var(--accent);font-weight:600;cursor:pointer;transition:all 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h3,.invoice-error h3{color:var(--accent);margin-bottom:10px}.preimage{font-size:.75rem;color:var(--text-muted);margin-top:10px}.spinner{width:40px;height:40px;border:3px solid rgba(255,255,255,.2);border-top-color:var(--accent);border-radius:50%;animation:spin 1s linear infinite;margin:20px auto}.invoice-loading{text-align:center;padding:40px 0}.evaluation-list{max-width:600px}.evaluation-item{background:#ffffff0d;border:1px solid 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10px;border-radius:var(--radius-sm);font-size:.85rem}.teacher-no-lightning{margin-top:10px;color:var(--warning);font-size:.9rem}.teacher-zap-section{margin-top:20px;padding-top:20px;border-top:1px solid var(--border-color)}@keyframes shimmer{0%{background-position:-200% 0}to{background-position:200% 0}}.skeleton{background:linear-gradient(90deg,var(--bg-card) 25%,rgba(255,255,255,.08) 50%,var(--bg-card) 75%);background-size:200% 100%;animation:shimmer 1.5s ease-in-out 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