:root{--primary-color:#4f46e5;--primary-hover:#4338ca;--secondary-color:#10b981;--secondary-hover:#059669;--bg-color:#0f172a;--card-bg:#1e293bb3;--text-primary:#f8fafc;--text-secondary:#94a3b8;--border-color:#ffffff1a;--shadow-sm:0 4px 6px -1px #0000001a, 0 2px 4px -1px #0000000f;--shadow-lg:0 10px 15px -3px #00000080, 0 4px 6px -2px #00000040}*{box-sizing:border-box;margin:0;padding:0}body{background-color:var(--bg-color);color:var(--text-primary);background-image:radial-gradient(circle at 15%,#4f46e526,#0000 25%),radial-gradient(circle at 85% 30%,#10b98126,#0000 25%);justify-content:center;align-items:center;min-height:100vh;font-family:Inter,-apple-system,BlinkMacSystemFont,Segoe UI,Roboto,Oxygen,Ubuntu,Cantarell,Open Sans,Helvetica Neue,sans-serif;display:flex}.app-container{width:100%;max-width:1000px;margin:0 auto;padding:2rem}header{text-align:center;margin-bottom:3rem}header h1{background:linear-gradient(90deg,#818cf8,#34d399);color:#0000;-webkit-background-clip:text;background-clip:text;margin-bottom:.5rem;font-size:2.5rem;font-weight:800}header p{color:var(--text-secondary);font-size:1.1rem}.home-grid{grid-template-columns:repeat(auto-fit,minmax(300px,1fr));gap:2rem;margin-top:2rem;display:grid}.tool-card{background:var(--card-bg);-webkit-backdrop-filter:blur(10px);backdrop-filter:blur(10px);border:1px solid var(--border-color);text-align:center;cursor:pointer;box-shadow:var(--shadow-sm);border-radius:1rem;flex-direction:column;align-items:center;gap:1rem;padding:2.5rem 2rem;transition:all .3s;display:flex}.tool-card:hover{box-shadow:var(--shadow-lg);border-color:#fff3;transform:translateY(-5px)}.tool-card:hover .icon-container{background:var(--primary-color);color:#fff}.tool-card.split:hover .icon-container{background:var(--primary-color)}.tool-card.combine:hover .icon-container{background:var(--secondary-color)}.icon-container{width:80px;height:80px;color:var(--text-primary);background:#ffffff0d;border-radius:50%;justify-content:center;align-items:center;margin-bottom:1rem;transition:all .3s;display:flex}.tool-card h2{margin-bottom:.5rem;font-size:1.5rem}.tool-card p{color:var(--text-secondary);font-size:.95rem;line-height:1.5}.tool-view{background:var(--card-bg);-webkit-backdrop-filter:blur(10px);backdrop-filter:blur(10px);border:1px solid var(--border-color);box-shadow:var(--shadow-lg);border-radius:1rem;padding:3rem}.back-btn{color:var(--text-secondary);cursor:pointer;background:0 0;border:none;align-items:center;gap:.5rem;margin-bottom:2rem;font-size:1rem;transition:color .2s;display:flex}.back-btn:hover{color:var(--text-primary)}.tool-header{text-align:center;margin-bottom:3rem}.tool-header h2{margin-bottom:.5rem;font-size:2rem}.tool-header p{color:var(--text-secondary)}.upload-zone{text-align:center;cursor:pointer;background:#0003;border:2px dashed #fff3;border-radius:1rem;margin-bottom:2rem;padding:4rem 2rem;transition:all .3s}.upload-zone:hover,.upload-zone.drag-active{border-color:var(--primary-color);background:#4f46e50d}.upload-zone input{display:none}.upload-icon{color:var(--text-secondary);margin-bottom:1rem;transition:color .3s}.upload-zone:hover .upload-icon{color:var(--primary-color)}.file-list{text-align:left;background:#0003;border-radius:.5rem;margin-top:1.5rem;padding:1rem}.file-item{border-bottom:1px solid #ffffff1a;align-items:center;gap:.5rem;padding:.5rem 0;display:flex}.file-item:last-child{border-bottom:none}.action-btn{background:var(--primary-color);color:#fff;cursor:pointer;border:none;border-radius:.5rem;justify-content:center;align-items:center;gap:.5rem;width:100%;padding:1rem;font-size:1.1rem;font-weight:600;transition:background .2s;display:flex}.action-btn:hover:not(:disabled){background:var(--primary-hover)}.action-btn:disabled{color:#ffffff4d;cursor:not-allowed;background:#ffffff1a}.action-btn.secondary{background:var(--secondary-color)}.action-btn.secondary:hover:not(:disabled){background:var(--secondary-hover)}@keyframes spin{0%{transform:rotate(0)}to{transform:rotate(360deg)}}.spin{animation:1s linear infinite spin}.status-message{text-align:center;border-radius:.5rem;margin-top:1.5rem;padding:1rem;font-weight:500}.status-message.success{color:#34d399;background:#10b9811a;border:1px solid #10b98133}.status-message.error{color:#f87171;background:#ef44441a;border:1px solid #ef444433}