:root{--primary-color:#4a9d5f;--accent-color:#5cb574;--text-primary:#1a1a1a;--text-secondary:#666;--border-color:#ddd;--bg-primary:#fff;--bg-secondary:#f5f5f5;--bg-highlight:#e8f5e9;--error-color:#d32f2f;--success-color:#388e3c;--shadow:0 2px 8px #0000001a}*{box-sizing:border-box}body{-webkit-font-smoothing:antialiased;-moz-osx-font-smoothing:grayscale;color:var(--text-primary);background:var(--bg-secondary);margin:0;font-family:-apple-system,BlinkMacSystemFont,Segoe UI,Roboto,Oxygen,Ubuntu,Cantarell,Fira Sans,Droid Sans,Helvetica Neue,sans-serif}.app{flex-direction:column;height:100vh;display:flex}.header{background:var(--primary-color);color:#fff;text-align:center;box-shadow:var(--shadow);padding:1.5rem}.header h1{margin:0;font-size:2rem;font-weight:700}.main{flex:1;padding-bottom:80px;overflow-y:auto}.tab-bar{background:var(--bg-primary);border-top:1px solid var(--border-color);z-index:100;display:flex;position:fixed;bottom:0;left:0;right:0;box-shadow:0 -2px 8px #0000000d}.tab-item{color:var(--text-secondary);cursor:pointer;flex-direction:column;flex:1;justify-content:center;align-items:center;padding:.75rem;text-decoration:none;transition:all .2s;display:flex}.tab-item:hover{background:var(--bg-secondary)}.tab-item.active{color:var(--primary-color)}.tab-icon{width:24px;height:24px;margin-bottom:.25rem}.tab-item span{font-size:.75rem;font-weight:500}.compare-screen{max-width:1400px;margin:0 auto;padding:1.5rem}.compare-inputs{grid-template-columns:1fr 1fr;gap:1rem;margin-bottom:1rem;display:grid}.input-group{flex-direction:column;gap:.5rem;display:flex}.input-group label{color:var(--text-primary);font-size:.875rem;font-weight:600}.input-group input{border:2px solid var(--border-color);border-radius:6px;padding:.75rem;font-family:inherit;font-size:1rem;transition:border-color .2s}.input-group input:focus{border-color:var(--primary-color);outline:none}.actions{flex-wrap:wrap;justify-content:center;gap:.75rem;margin-bottom:1.5rem;display:flex}.btn{cursor:pointer;border:none;border-radius:6px;padding:.75rem 1.5rem;font-family:inherit;font-size:1rem;font-weight:600;transition:all .2s}.btn:hover{box-shadow:var(--shadow);transform:translateY(-1px)}.btn:active{transform:translateY(0)}.btn-primary{background:var(--primary-color);color:#fff}.btn-primary:hover{background:var(--accent-color)}.btn-secondary{background:var(--bg-primary);color:var(--text-primary);border:2px solid var(--border-color)}.btn-secondary:hover{background:var(--bg-secondary)}.comparison-area{grid-template-columns:1fr 1fr;gap:1rem;margin-bottom:1.5rem;display:grid}.text-panel{background:var(--bg-primary);border:2px solid var(--border-color);border-radius:8px;flex-direction:column;gap:.75rem;padding:1rem;display:flex}.panel-header{border-bottom:1px solid var(--border-color);justify-content:space-between;align-items:center;padding-bottom:.5rem;display:flex}.panel-title{color:var(--primary-color);font-weight:600}.stats{color:var(--text-secondary);font-size:.875rem}.text-display{background:var(--bg-secondary);white-space:pre-wrap;word-break:break-word;border-radius:6px;min-height:300px;padding:1rem;font-family:Courier New,monospace;line-height:1.6}.diff-added{background:#c8e6c9;padding:2px 0}.diff-removed{background:#ffcdd2;padding:2px 0;text-decoration:line-through}.save-section{text-align:center}.history-screen{max-width:1200px;margin:0 auto;padding:1.5rem}.history-empty{text-align:center;padding:4rem 2rem}.empty-icon{width:80px;height:80px;color:var(--text-secondary);margin:0 auto 1.5rem}.history-empty h2{color:var(--text-secondary);margin-bottom:.5rem}.history-empty p{color:var(--text-secondary);margin-bottom:1.5rem}.history-list{flex-direction:column;gap:1rem;display:flex}.history-item{background:var(--bg-primary);border:2px solid var(--border-color);box-shadow:var(--shadow);border-radius:8px;padding:1.5rem;transition:transform .2s}.history-item:hover{transform:translateY(-2px);box-shadow:0 4px 12px #00000026}.history-header{justify-content:space-between;align-items:center;margin-bottom:1rem;display:flex}.history-date{color:var(--text-secondary);font-size:.875rem}.history-actions{gap:.5rem;display:flex}.btn-icon{cursor:pointer;color:var(--text-secondary);background:0 0;border:none;border-radius:4px;padding:.5rem;transition:all .2s}.btn-icon:hover{background:var(--bg-secondary);color:var(--primary-color)}.icon{width:20px;height:20px}.history-content{grid-template-columns:1fr 1fr;gap:1rem;display:grid}.history-text{background:var(--bg-secondary);white-space:pre-wrap;word-break:break-word;border-radius:6px;max-height:150px;padding:1rem;font-family:Courier New,monospace;font-size:.875rem;overflow-y:auto}.history-differences{background:var(--bg-highlight);color:var(--text-primary);border-radius:6px;grid-column:1/-1;margin-top:.5rem;padding:1rem;font-size:.875rem}@media (width<=768px){.compare-inputs,.comparison-area,.history-content{grid-template-columns:1fr}.header h1{font-size:1.5rem}.compare-screen,.history-screen{padding:1rem}.actions{flex-direction:column}.btn{width:100%}}