:root{--primary: #4f46e5;--primary-hover: #4338ca;--bg: #f8fafc;--surface: #ffffff;--text: #1e293b;--text-secondary: #64748b;--border: #e2e8f0;--radius: 8px;--shadow: 0 1px 3px rgba(0, 0, 0, .1), 0 1px 2px rgba(0, 0, 0, .06);--shadow-md: 0 4px 6px rgba(0, 0, 0, .07), 0 2px 4px rgba(0, 0, 0, .06);--shadow-lg: 0 10px 15px rgba(0, 0, 0, .1), 0 4px 6px rgba(0, 0, 0, .05)}*,*:before,*:after{margin:0;padding:0;box-sizing:border-box}html{font-size:16px;-webkit-text-size-adjust:100%}body{font-family:-apple-system,BlinkMacSystemFont,Segoe UI,Roboto,Helvetica Neue,Arial,Noto Sans SC,sans-serif;background-color:var(--bg);color:var(--text);line-height:1.6;min-height:100vh}a{color:inherit;text-decoration:none}img{max-width:100%;height:auto}button{cursor:pointer;font-family:inherit}.app{display:flex;flex-direction:column;min-height:100vh}.header{position:sticky;top:0;z-index:1000;background:var(--surface);box-shadow:var(--shadow)}.header-inner{max-width:1200px;margin:0 auto;padding:0 16px;display:flex;align-items:center;height:60px;gap:24px}.logo{display:flex;align-items:center;gap:8px;color:var(--primary);flex-shrink:0}.logo-text{font-size:1.2rem;font-weight:700;white-space:nowrap}.nav-links{display:flex;align-items:center;gap:4px;overflow-x:auto;scrollbar-width:none;-ms-overflow-style:none;flex:1}.nav-links::-webkit-scrollbar{display:none}.nav-link{padding:8px 12px;font-size:.875rem;color:var(--text-secondary);white-space:nowrap;border-radius:var(--radius);transition:color .2s,background-color .2s;border-bottom:2px solid transparent}.nav-link:hover{color:var(--primary);background-color:#4f46e50d}.nav-link.active{color:var(--primary);font-weight:600;border-bottom-color:var(--primary)}.hamburger{display:none;flex-direction:column;gap:5px;background:none;border:none;padding:8px;cursor:pointer}.hamburger-line{display:block;width:22px;height:2px;background:var(--text);border-radius:2px;transition:transform .3s,opacity .3s}.hamburger-line.open:nth-child(1){transform:rotate(45deg) translate(5px,5px)}.hamburger-line.open:nth-child(2){opacity:0}.hamburger-line.open:nth-child(3){transform:rotate(-45deg) translate(5px,-5px)}.main-content{max-width:1200px;margin:0 auto;padding:24px 16px;width:100%;flex:1}.upload-zone{border:2px dashed var(--border);border-radius:var(--radius);padding:40px 24px;text-align:center;cursor:pointer;transition:border-color .2s,background-color .2s;background:var(--surface)}.upload-zone:hover{border-color:var(--primary);background-color:#4f46e505}.upload-zone-active{border-color:var(--primary);background-color:#4f46e50d}.upload-icon{color:var(--text-secondary);margin-bottom:12px}.upload-text{font-size:1rem;color:var(--text);margin-bottom:8px}.upload-hint{font-size:.8rem;color:var(--text-secondary)}.upload-file-list{margin-top:16px;display:flex;flex-wrap:wrap;gap:8px;justify-content:center}.upload-file-name{display:inline-block;padding:4px 10px;background:#4f46e514;border-radius:4px;font-size:.8rem;color:var(--primary);max-width:200px;overflow:hidden;text-overflow:ellipsis;white-space:nowrap}.preview-area{position:relative;border-radius:var(--radius);overflow:hidden;background-image:linear-gradient(45deg,#f0f0f0 25%,transparent 25%),linear-gradient(-45deg,#f0f0f0 25%,transparent 25%),linear-gradient(45deg,transparent 75%,#f0f0f0 75%),linear-gradient(-45deg,transparent 75%,#f0f0f0 75%);background-size:20px 20px;background-position:0 0,0 10px,10px -10px,-10px 0;background-color:#fff;min-height:200px;display:flex;align-items:center;justify-content:center}.preview-image{cursor:zoom-in;transition:transform .3s}.preview-zoomed .preview-image{cursor:zoom-out;transform:scale(1.5)}.preview-loading,.preview-error{display:flex;flex-direction:column;align-items:center;gap:8px;color:var(--text-secondary);padding:40px}.preview-empty{color:var(--text-secondary)}.btn{display:inline-flex;align-items:center;justify-content:center;gap:8px;padding:10px 20px;font-size:.9rem;font-weight:500;border:none;border-radius:var(--radius);background:var(--primary);color:#fff;transition:background-color .2s,transform .1s}.btn:hover:not(:disabled){background:var(--primary-hover)}.btn:active:not(:disabled){transform:scale(.98)}.btn:disabled{opacity:.5;cursor:not-allowed}.btn-secondary{background:transparent;color:var(--primary);border:1px solid var(--primary)}.btn-secondary:hover:not(:disabled){background:#4f46e50d}.card{background:var(--surface);border:1px solid var(--border);border-radius:var(--radius);box-shadow:var(--shadow);transition:transform .2s,box-shadow .2s}.card:hover{transform:translateY(-2px);box-shadow:var(--shadow-md)}.tool-card{display:flex;flex-direction:column;align-items:flex-start;padding:24px;gap:12px}.tool-card-icon{width:44px;height:44px;display:flex;align-items:center;justify-content:center;border-radius:var(--radius);background:#4f46e514;color:var(--primary)}.tool-card-title{font-size:1rem;font-weight:600}.tool-card-desc{font-size:.85rem;color:var(--text-secondary);line-height:1.5}.ad-slot{display:flex;flex-direction:column;align-items:center;justify-content:center;gap:4px;border:1px dashed var(--border);border-radius:var(--radius);background:#f9fafb;margin:16px 0}.ad-slot-text{font-size:.8rem;color:var(--text-secondary)}.ad-slot-size{font-size:.7rem;color:#94a3b8}.tool-grid{display:grid;grid-template-columns:repeat(auto-fill,minmax(280px,1fr));gap:20px}.control-panel{display:flex;flex-direction:column;gap:16px}.slider-control{display:flex;flex-direction:column;gap:8px}.slider-header{display:flex;justify-content:space-between;align-items:center}.slider-label{font-size:.875rem;font-weight:500;color:var(--text)}.slider-value{font-size:.8rem;color:var(--primary);font-weight:600}.slider-input{-webkit-appearance:none;-moz-appearance:none;appearance:none;width:100%;height:6px;border-radius:3px;background:var(--border);outline:none;cursor:pointer}.slider-input::-webkit-slider-thumb{-webkit-appearance:none;-moz-appearance:none;appearance:none;width:18px;height:18px;border-radius:50%;background:var(--primary);cursor:pointer;transition:transform .1s}.slider-input::-webkit-slider-thumb:hover{transform:scale(1.15)}.slider-input::-moz-range-thumb{width:18px;height:18px;border-radius:50%;background:var(--primary);cursor:pointer;border:none}.tool-page{display:flex;flex-direction:column;gap:8px}.tool-page-header{margin-bottom:16px}.tool-page-title{font-size:1.5rem;font-weight:700;margin-bottom:8px}.tool-page-desc{font-size:.9rem;color:var(--text-secondary)}.tool-page-content{display:flex;flex-direction:column;gap:24px}.footer{border-top:1px solid var(--border);padding:24px 16px;text-align:center;background:var(--surface);margin-top:auto}.footer-inner{max-width:1200px;margin:0 auto}.footer-copyright{font-size:.8rem;color:var(--text-secondary);margin-bottom:12px}.footer-links{display:flex;justify-content:center;gap:24px}.footer-links a{font-size:.8rem;color:var(--text-secondary);transition:color .2s}.footer-links a:hover{color:var(--primary)}.spinner{width:24px;height:24px;border:3px solid var(--border);border-top-color:var(--primary);border-radius:50%;animation:spin .8s linear infinite}.spinner-sm{width:16px;height:16px;border-width:2px}@keyframes spin{to{transform:rotate(360deg)}}.toast{position:fixed;bottom:24px;left:50%;transform:translate(-50%);padding:12px 24px;background:var(--text);color:#fff;border-radius:var(--radius);font-size:.875rem;box-shadow:var(--shadow-lg);z-index:9999;animation:toast-in .3s ease}@keyframes toast-in{0%{opacity:0;transform:translate(-50%) translateY(10px)}to{opacity:1;transform:translate(-50%) translateY(0)}}.hero{text-align:center;padding:48px 16px}.hero-title{font-size:2rem;font-weight:800;margin-bottom:12px;color:var(--text)}.hero-subtitle{font-size:1rem;color:var(--text-secondary);max-width:600px;margin:0 auto}.features-section{margin-top:48px}.features-title{text-align:center;font-size:1.3rem;font-weight:700;margin-bottom:24px}.features-grid{display:grid;grid-template-columns:repeat(auto-fill,minmax(240px,1fr));gap:16px}.feature-item{display:flex;align-items:flex-start;gap:12px;padding:20px;background:var(--surface);border-radius:var(--radius);border:1px solid var(--border)}.feature-icon{width:36px;height:36px;display:flex;align-items:center;justify-content:center;border-radius:50%;background:#4f46e514;color:var(--primary);flex-shrink:0}.feature-text h4{font-size:.9rem;font-weight:600;margin-bottom:4px}.feature-text p{font-size:.8rem;color:var(--text-secondary)}.section-title{font-size:1.3rem;font-weight:700;margin-bottom:20px;margin-top:40px}@media (max-width: 768px){.header-inner{flex-wrap:wrap;height:auto;padding:12px 16px}.hamburger{display:flex;margin-left:auto}.nav-links{display:none;flex-direction:column;width:100%;padding-top:12px;gap:2px}.nav-links.nav-open{display:flex}.nav-link{padding:10px 12px;border-bottom:none;border-radius:var(--radius)}.nav-link.active{background:#4f46e514;border-bottom:none}.hero-title{font-size:1.5rem}.tool-grid,.features-grid{grid-template-columns:1fr}}@media (max-width: 480px){.main-content{padding:16px 12px}.hero{padding:32px 8px}.hero-title{font-size:1.3rem}.hero-subtitle{font-size:.875rem}.upload-zone{padding:24px 16px}.tool-card{padding:16px}}