:root{--primary:#8b5cf6;--primary-dark:#7c3aed;--primary-light:#a78bfa;--accent:#6366f1;--accent-dark:#4f46e5;--background:#fff;--surface:#f9fafb;--border:#e5e7eb;--text:#111827;--text-secondary:#6b7280;--text-muted:#9ca3af;--success:#10b981;--warning:#f59e0b;--danger:#ef4444;--shadow:#0000001a}*{box-sizing:border-box;margin:0;padding:0}body{-webkit-font-smoothing:antialiased;-moz-osx-font-smoothing:grayscale;background:var(--background);color:var(--text);font-family:-apple-system,BlinkMacSystemFont,Segoe UI,Roboto,Oxygen,Ubuntu,Cantarell,Fira Sans,Droid Sans,Helvetica Neue,sans-serif;line-height:1.6}#root{flex-direction:column;min-height:100vh;display:flex}.header{background:var(--primary);color:#fff;box-shadow:0 2px 4px var(--shadow);z-index:100;align-items:center;gap:1rem;padding:1rem 1.5rem;display:flex;position:sticky;top:0}.back-button{color:#fff;cursor:pointer;background:0 0;border:none;border-radius:.25rem;justify-content:center;align-items:center;width:2rem;height:2rem;padding:.25rem;font-size:1.5rem;transition:background .2s;display:flex}.back-button:hover{background:#ffffff1a}.header h1{margin:0;font-size:1.5rem;font-weight:600}.main-content{flex:1;width:100%;max-width:1200px;margin:0 auto;padding:1.5rem}.button{background:var(--primary);color:#fff;cursor:pointer;border:none;border-radius:.5rem;align-items:center;gap:.5rem;padding:.75rem 1.5rem;font-size:1rem;font-weight:500;text-decoration:none;transition:background .2s,transform .1s;display:inline-flex}.button:hover{background:var(--primary-dark);transform:translateY(-1px)}.button:active{transform:translateY(0)}.button-secondary{background:var(--surface);color:var(--text);border:1px solid var(--border)}.button-secondary:hover{background:var(--border)}.button-danger{background:var(--danger)}.button-danger:hover{background:#dc2626}.button-small{padding:.5rem 1rem;font-size:.875rem}.filter-bar{flex-wrap:wrap;gap:.5rem;margin-bottom:1.5rem;display:flex}.filter-button{background:var(--surface);border:2px solid var(--border);color:var(--text);cursor:pointer;border-radius:2rem;padding:.5rem 1rem;font-size:.875rem;font-weight:500;transition:all .2s}.filter-button:hover{border-color:var(--primary);color:var(--primary)}.filter-button.active{background:var(--primary);border-color:var(--primary);color:#fff}.books-grid{grid-template-columns:repeat(auto-fill,minmax(300px,1fr));gap:1.5rem;display:grid}.book-card{border:1px solid var(--border);background:#fff;border-radius:.75rem;padding:1.5rem;transition:box-shadow .2s,transform .2s}.book-card:hover{box-shadow:0 4px 12px var(--shadow);transform:translateY(-2px)}.book-card-header{justify-content:space-between;align-items:flex-start;margin-bottom:.75rem;display:flex}.book-title{color:var(--text);margin-bottom:.25rem;font-size:1.25rem;font-weight:600}.book-author{color:var(--text-secondary);margin-bottom:.75rem;font-size:.875rem}.book-status{text-transform:uppercase;letter-spacing:.025em;border-radius:1rem;padding:.25rem .75rem;font-size:.75rem;font-weight:600;display:inline-block}.book-status.want-to-read{color:#1e40af;background:#dbeafe}.book-status.reading{color:#92400e;background:#fef3c7}.book-status.completed{color:#065f46;background:#d1fae5}.book-actions{border-top:1px solid var(--border);gap:.5rem;margin-top:1rem;padding-top:1rem;display:flex}.icon-button{color:var(--text-secondary);cursor:pointer;background:0 0;border:none;border-radius:.25rem;padding:.5rem;font-size:1rem;transition:all .2s}.icon-button:hover{background:var(--surface);color:var(--primary)}.icon-button.danger:hover{color:var(--danger)}.empty-state{text-align:center;padding:4rem 2rem}.empty-state-icon{opacity:.3;margin-bottom:1rem;font-size:4rem}.empty-state h2{color:var(--text);margin-bottom:.5rem;font-size:1.5rem}.empty-state p{color:var(--text-secondary);margin-bottom:1.5rem}.form{border:1px solid var(--border);background:#fff;border-radius:.75rem;max-width:600px;padding:2rem}.form-group{margin-bottom:1.5rem}.form-label{color:var(--text);margin-bottom:.5rem;font-weight:500;display:block}.form-input,.form-select{border:1px solid var(--border);border-radius:.5rem;width:100%;padding:.75rem;font-family:inherit;font-size:1rem;transition:border-color .2s,box-shadow .2s}.form-input:focus,.form-select:focus{border-color:var(--primary);outline:none;box-shadow:0 0 0 3px #8b5cf61a}.form-actions{gap:1rem;margin-top:2rem;display:flex}.form-actions .button{flex:1}.top-bar{flex-wrap:wrap;justify-content:space-between;align-items:center;gap:1rem;margin-bottom:2rem;display:flex}.top-bar h2{color:var(--text);font-size:1.75rem;font-weight:600}.stats-bar{flex-wrap:wrap;gap:1rem;margin-bottom:2rem;display:flex}.stat-card{border:1px solid var(--border);background:#fff;border-radius:.5rem;flex:1;min-width:150px;padding:1rem 1.5rem}.stat-value{color:var(--primary);font-size:2rem;font-weight:700;display:block}.stat-label{color:var(--text-secondary);text-transform:uppercase;letter-spacing:.025em;font-size:.875rem}@media (width<=768px){.main-content{padding:1rem}.books-grid{grid-template-columns:1fr}.form{padding:1.5rem}.header{padding:1rem}.header h1{font-size:1.25rem}}