:root{--color-bg-primary:#0a0f1e;--color-bg-secondary:#111827;--color-bg-card:#111827b3;--color-bg-card-hover:#1e293bcc;--color-bg-glass:#ffffff0a;--color-bg-glass-hover:#ffffff14;--color-accent:#3b82f6;--color-accent-light:#60a5fa;--color-accent-dark:#2563eb;--color-accent-glow:#3b82f64d;--color-accent-subtle:#3b82f61a;--gradient-primary:linear-gradient(135deg, #3b82f6 0%, #8b5cf6 100%);--gradient-secondary:linear-gradient(135deg, #1e3a5f 0%, #0a0f1e 100%);--gradient-accent:linear-gradient(135deg, #3b82f6 0%, #06b6d4 100%);--gradient-success:linear-gradient(135deg, #10b981 0%, #34d399 100%);--gradient-bg:radial-gradient(ellipse at top, #1e3a5f 0%, #0a0f1e 60%);--color-text-primary:#f1f5f9;--color-text-secondary:#94a3b8;--color-text-muted:#64748b;--color-text-accent:#60a5fa;--color-border:#ffffff14;--color-border-hover:#ffffff26;--color-border-accent:#3b82f666;--color-success:#10b981;--color-error:#ef4444;--color-warning:#f59e0b;--space-xs:4px;--space-sm:8px;--space-md:16px;--space-lg:24px;--space-xl:32px;--space-2xl:48px;--space-3xl:64px;--radius-sm:8px;--radius-md:12px;--radius-lg:16px;--radius-xl:24px;--radius-full:9999px;--shadow-sm:0 2px 8px #0003;--shadow-md:0 4px 16px #0000004d;--shadow-lg:0 8px 32px #0006;--shadow-glow:0 0 30px #3b82f626;--shadow-glow-strong:0 0 60px #3b82f640;--transition-fast:.15s cubic-bezier(.4, 0, .2, 1);--transition-base:.25s cubic-bezier(.4, 0, .2, 1);--transition-slow:.4s cubic-bezier(.4, 0, .2, 1);--transition-spring:.5s cubic-bezier(.34, 1.56, .64, 1);--font-family:"Inter", -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif}*,:before,:after{box-sizing:border-box;margin:0;padding:0}html{scroll-behavior:smooth;-webkit-font-smoothing:antialiased;-moz-osx-font-smoothing:grayscale;font-size:16px}body{font-family:var(--font-family);background:var(--color-bg-primary);color:var(--color-text-primary);min-height:100vh;line-height:1.6;overflow-x:hidden}body:before{content:"";background:var(--gradient-bg);z-index:-2;position:fixed;inset:0}body:after{content:"";z-index:-1;background:radial-gradient(circle at 20% 20%,#3b82f60d 0%,#0000 50%),radial-gradient(circle at 80% 80%,#8b5cf60d 0%,#0000 50%);width:200%;height:200%;animation:20s ease-in-out infinite alternate bgShift;position:fixed;top:-50%;left:-50%}@keyframes bgShift{0%{transform:translate(0)}to{transform:translate(-5%,-5%)}}#root{flex-direction:column;min-height:100vh;display:flex}::-webkit-scrollbar{width:6px}::-webkit-scrollbar-track{background:0 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float{0%,to{transform:translateY(0)}50%{transform:translateY(-8px)}}.animate-fade-in-up{animation:fadeInUp .5s var(--transition-base) forwards}.animate-fade-in{animation:.4s forwards fadeIn}.animate-scale-in{animation:scaleIn .4s var(--transition-spring) forwards}.glass-card{background:var(--color-bg-card);-webkit-backdrop-filter:blur(20px);border:1px solid var(--color-border);border-radius:var(--radius-lg);transition:all var(--transition-base)}.glass-card:hover{border-color:var(--color-border-hover);box-shadow:var(--shadow-glow)}.btn{justify-content:center;align-items:center;gap:var(--space-sm);padding:var(--space-md) var(--space-xl);border-radius:var(--radius-md);font-family:var(--font-family);cursor:pointer;transition:all var(--transition-base);-webkit-user-select:none;user-select:none;border:none;font-size:.95rem;font-weight:600;display:inline-flex;position:relative;overflow:hidden}.btn:disabled{opacity:.5;cursor:not-allowed}.btn-primary{background:var(--gradient-primary);color:#fff;box-shadow:var(--shadow-md), 0 0 20px #3b82f633;background-size:200% 200%;animation:3s infinite gradientMove}.btn-primary:hover:not(:disabled){box-shadow:var(--shadow-lg), var(--shadow-glow-strong);transform:translateY(-2px)}.btn-primary:active:not(:disabled){transform:translateY(0)}.btn-secondary{background:var(--color-bg-glass);color:var(--color-text-primary);border:1px solid var(--color-border)}.btn-secondary:hover:not(:disabled){background:var(--color-bg-glass-hover);border-color:var(--color-border-hover)}.btn-success{background:var(--gradient-success);color:#fff;box-shadow:0 0 20px #10b98133}.btn-success:hover:not(:disabled){transform:translateY(-2px);box-shadow:0 0 40px #10b9814d}@media (width<=768px){:root{--space-2xl:32px;--space-3xl:48px}}@media (width<=480px){:root{--space-xl:24px;--space-2xl:24px;--space-3xl:32px}html{font-size:14px}}.main{padding:var(--space-2xl) var(--space-xl);flex-direction:column;flex:1;align-items:center;width:100%;max-width:1200px;margin:0 auto;display:flex}.hero{text-align:center;margin-bottom:var(--space-2xl)}.hero-badge{background:var(--color-accent-subtle);border-radius:var(--radius-full);color:var(--color-accent-light);margin-bottom:var(--space-lg);border:1px solid #3b82f633;align-items:center;gap:6px;padding:6px 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var(--color-border);border-radius:var(--radius-xl);width:100%;padding:var(--space-md) var(--space-lg);align-items:center;gap:var(--space-md);box-shadow:var(--shadow-sm);transition:all var(--transition-base);display:flex;position:relative}.file-card:hover{box-shadow:var(--shadow-md);background:var(--color-surface);border-color:#ffffff26}.file-card-icon{border-radius:var(--radius-md);background:#ffffff08;flex-shrink:0;justify-content:center;align-items:center;width:48px;height:48px;display:flex}.file-card-details{flex-direction:column;flex:1;gap:4px;min-width:0;display:flex}.file-card-name{color:var(--color-text-primary);white-space:nowrap;text-overflow:ellipsis;font-size:1rem;font-weight:500;overflow:hidden}.file-card-size{color:var(--color-text-muted);font-size:.8rem}.file-card-delete{border-radius:var(--radius-full);width:36px;height:36px;color:var(--color-text-muted);cursor:pointer;transition:all var(--transition-base);background:0 0;border:1px solid #0000;flex-shrink:0;justify-content:center;align-items:center;display:flex}.file-card-delete:hover{color:#ef4444;background:#ef44441a;border-color:#ef444433}.add-more-btn{justify-content:center;align-items:center;gap:var(--space-sm);width:100%;padding:var(--space-md);border:1px dashed var(--color-border);border-radius:var(--radius-xl);color:var(--color-text-secondary);cursor:pointer;transition:all var(--transition-base);background:0 0;font-size:.95rem;font-weight:500;display:flex}.add-more-btn:hover{color:var(--color-text-primary);border-color:var(--color-text-muted);background:#ffffff05}.workspace-action{gap:var(--space-xl);flex-direction:column;width:100%;display:flex}.content-area{flex-direction:column;align-items:center;width:100%;display:flex}.select-step{align-items:center;gap:var(--space-xl);flex-direction:column;width:100%;display:flex}.converting-step{flex-direction:column;align-items:center;width:100%;display:flex}.global-error{align-items:center;gap:var(--space-sm);padding:var(--space-md);border-radius:var(--radius-md);color:#fca5a5;background:#ef44441a;border:1px solid #ef444440;width:100%;max-width:560px;font-size:.85rem;display:flex}@media (width<=768px){.main{padding:var(--space-xl) var(--space-md)}}@media (width<=480px){.step-label{display:none}.step-line{width:24px}}.header{padding:var(--space-md) var(--space-xl);border-bottom:1px solid var(--color-border);-webkit-backdrop-filter:blur(20px);z-index:100;background:#0a0f1ecc;position:sticky;top:0}.header-inner{justify-content:space-between;align-items:center;max-width:1200px;margin:0 auto;display:flex}.header-logo{align-items:center;gap:var(--space-sm);display:flex}.logo-icon{background:var(--color-accent-subtle);border-radius:var(--radius-md);width:40px;height:40px;transition:all var(--transition-base);justify-content:center;align-items:center;display:flex}.logo-icon:hover{background:#3b82f633;transform:scale(1.05)}.logo-text{color:var(--color-text-primary);letter-spacing:-.02em;font-size:1.3rem;font-weight:700}.logo-accent{background:var(--gradient-primary);-webkit-text-fill-color:transparent;-webkit-background-clip:text;background-clip:text}.header-badge{background:var(--color-bg-glass);border:1px solid var(--color-border);border-radius:var(--radius-full);color:var(--color-text-secondary);align-items:center;gap:6px;padding:6px 14px;font-size:.78rem;font-weight:500;display:flex}.badge-dot{background:var(--color-success);border-radius:50%;width:6px;height:6px;animation:2s ease-in-out infinite pulse}@media (width<=480px){.header{padding:var(--space-sm) var(--space-md)}.logo-text{font-size:1.1rem}}.footer{padding:var(--space-lg) var(--space-xl);border-top:1px solid var(--color-border);margin-top:auto}.footer-inner{text-align:center;max-width:1200px;margin:0 auto}.footer-text{color:var(--color-text-muted);margin-bottom:4px;font-size:.85rem}.footer-sub{color:var(--color-text-muted);opacity:.7;font-size:.75rem}.uploader-wrapper{width:100%;max-width:560px;margin:0 auto}.upload-zone{padding:var(--space-3xl) var(--space-xl);border:2px dashed var(--color-border);border-radius:var(--radius-xl);background:var(--color-bg-glass);cursor:pointer;transition:all var(--transition-base);flex-direction:column;justify-content:center;align-items:center;min-height:280px;display:flex;position:relative}.upload-zone:hover{border-color:var(--color-accent);background:var(--color-accent-subtle);box-shadow:var(--shadow-glow)}.upload-zone.dragging{border-color:var(--color-accent-light);box-shadow:var(--shadow-glow-strong);background:#3b82f61f;border-style:solid;animation:1.5s ease-in-out infinite borderGlow;transform:scale(1.02)}.upload-zone.has-file{border-style:solid;border-color:var(--color-border-hover);padding:var(--space-xl);cursor:default;min-height:auto}.upload-input{display:none}.upload-icon{color:var(--color-text-muted);margin-bottom:var(--space-lg);transition:all var(--transition-base);animation:3s ease-in-out infinite float}.upload-zone:hover .upload-icon{color:var(--color-accent);transform:scale(1.1)}.upload-title{color:var(--color-text-primary);margin-bottom:var(--space-xs);font-size:1.2rem;font-weight:600}.upload-subtitle{color:var(--color-text-muted);margin-bottom:var(--space-lg);font-size:.9rem}.upload-formats{gap:var(--space-sm);margin-bottom:var(--space-md);flex-wrap:wrap;justify-content:center;display:flex}.format-tag{background:var(--color-bg-glass);border:1px solid var(--color-border);border-radius:var(--radius-full);color:var(--color-text-secondary);letter-spacing:.04em;text-transform:uppercase;padding:4px 12px;font-size:.72rem;font-weight:600}.upload-limit{color:var(--color-text-muted);font-size:.78rem}.file-preview{align-items:center;gap:var(--space-md);width:100%;display:flex}.file-icon{background:var(--color-bg-glass);border-radius:var(--radius-md);flex-shrink:0;justify-content:center;align-items:center;width:52px;height:52px;display:flex}.file-details{flex:1;min-width:0}.file-name{color:var(--color-text-primary);white-space:nowrap;text-overflow:ellipsis;font-size:.95rem;font-weight:600;overflow:hidden}.file-size{color:var(--color-text-muted);margin-top:2px;font-size:.82rem}.file-status{color:var(--color-accent-light);flex-shrink:0;font-size:.82rem;animation:1.5s ease-in-out infinite pulse}.upload-error{align-items:center;gap:var(--space-sm);margin-top:var(--space-md);padding:var(--space-md);border-radius:var(--radius-md);color:#fca5a5;background:#ef44441a;border:1px solid #ef444440;font-size:.85rem;display:flex}@media (width<=480px){.upload-zone{padding:var(--space-2xl) var(--space-md);min-height:220px}}.format-selector{width:100%;max-width:560px;margin:0 auto}.selector-title{color:var(--color-text-primary);margin-bottom:var(--space-lg);text-align:center;font-size:1.05rem;font-weight:600}.format-grid{gap:var(--space-sm);flex-direction:column;display:flex}.format-card{align-items:center;gap:var(--space-md);width:100%;padding:var(--space-md) var(--space-lg);background:var(--color-bg-glass);border:1px solid var(--color-border);border-radius:var(--radius-md);cursor:pointer;transition:all var(--transition-base);font-family:var(--font-family);text-align:left;opacity:0;animation:.4s forwards fadeInUp;display:flex;position:relative}.format-card:hover{background:var(--color-bg-glass-hover);border-color:var(--format-color,var(--color-border-hover));transform:translate(4px)}.format-card.selected{border-color:var(--color-accent);background:#3b82f61a;box-shadow:0 0 20px #3b82f61a}.format-card-icon{background:var(--color-bg-glass);border-radius:var(--radius-sm);width:42px;height:42px;transition:all var(--transition-base);flex-shrink:0;justify-content:center;align-items:center;display:flex}.format-card:hover .format-card-icon{transform:scale(1.1)}.format-card-info{flex-direction:column;flex:1;display:flex}.format-card-label{color:var(--color-text-primary);letter-spacing:.01em;font-size:.92rem;font-weight:600}.format-card-desc{color:var(--color-text-muted);margin-top:2px;font-size:.78rem}.format-check{color:var(--color-accent);animation:.4s forwards bounceIn}@media (width<=480px){.format-card{padding:var(--space-sm) var(--space-md)}}.convert-section{width:100%;max-width:560px;margin:0 auto}.convert-btn{width:100%;padding:var(--space-lg) var(--space-xl);border-radius:var(--radius-lg);font-size:1.05rem}.progress-container{width:100%;padding:var(--space-lg);background:var(--color-bg-glass);border:1px solid var(--color-border);border-radius:var(--radius-lg)}.progress-bar-wrapper{border-radius:var(--radius-full);width:100%;height:8px;margin-bottom:var(--space-md);background:#ffffff0f;overflow:hidden}.progress-bar-fill{background:var(--gradient-primary);border-radius:var(--radius-full);background-size:200% 200%;height:100%;transition:width .6s cubic-bezier(.4,0,.2,1);animation:2s infinite gradientMove;position:relative}.progress-bar-fill:after{content:"";background:linear-gradient(90deg,#0000 0%,#ffffff4d 50%,#0000 100%) 0 0/200% 100%;animation:1.5s ease-in-out infinite shimmer;position:absolute;inset:0}.progress-info{justify-content:space-between;align-items:center;display:flex}.progress-status{align-items:center;gap:var(--space-sm);color:var(--color-text-secondary);font-size:.88rem;display:flex}.progress-spinner{border:2px solid var(--color-border);border-top-color:var(--color-accent);border-radius:50%;flex-shrink:0;width:14px;height:14px;animation:.8s linear infinite spin}.progress-percent{color:var(--color-accent-light);font-size:.88rem;font-weight:600}.download-panel{text-align:center;width:100%;max-width:560px;padding:var(--space-2xl);background:var(--color-bg-glass);border:1px solid var(--color-border);border-radius:var(--radius-xl);margin:0 auto}.success-animation{margin-bottom:var(--space-lg)}.success-circle{display:inline-block}.success-circle-anim{transform-origin:50%;animation:.6s .2s forwards circleReveal;transform:rotate(-90deg)}@keyframes circleReveal{to{stroke-dashoffset:0}}.success-check-anim{animation:.4s .7s forwards checkReveal}@keyframes checkReveal{to{stroke-dashoffset:0}}.download-title{color:var(--color-success);margin-bottom:var(--space-sm);font-size:1.5rem;font-weight:700}.download-subtitle{color:var(--color-text-secondary);margin-bottom:var(--space-sm);font-size:.92rem;line-height:1.5}.download-filename{color:var(--color-text-primary);font-weight:600}.download-format{color:var(--color-accent-light);font-weight:700}.download-size{color:var(--color-text-muted);margin-bottom:var(--space-xl);font-size:.82rem}.download-actions{gap:var(--space-sm);flex-direction:column;display:flex}.download-btn{width:100%;padding:var(--space-lg);border-radius:var(--radius-md);font-size:1.05rem}.reset-btn{width:100%;padding:var(--space-md);border-radius:var(--radius-md)}@media (width<=480px){.download-panel{padding:var(--space-xl) var(--space-md)}}