:root{--primary-color:#4361ee;--secondary-color:#3a0ca3;--accent-color:#7209b7;--light-color:#f8f9fa;--dark-color:#212529;--gray-color:#6c757d;--success-color:#4cc9f0;--warning-color:#f72585;--diff-del-bg:#ffeef0;--diff-del-color:#b31d28;--diff-add-bg:#e6ffec;--diff-add-color:#22863a;--old-text-color:#e95420;--new-text-color:#10b981;--border-radius:12px;--box-shadow:0 8px 24px rgba(0,0,0,0.1);--transition:all 0.3s ease}*{margin:0;padding:0;box-sizing:border-box;font-family:'Segoe UI','Microsoft YaHei',sans-serif}body{background-color:#f0f2f5;color:var(--dark-color);line-height:1.6}.container{width:100%;max-width:1200px;margin:0 auto;padding:0 20px}header{background:linear-gradient(135deg,var(--primary-color),var(--secondary-color));color:white;padding:20px 0;box-shadow:0 4px 12px rgba(0,0,0,0.1);position:sticky;top:0;z-index:100}.header-content{display:flex;justify-content:space-between;align-items:center}.logo{display:flex;align-items:center;gap:15px}.logo i{font-size:2.5rem}.logo h1{font-size:1.8rem;font-weight:700}.logo span{color:var(--success-color)}nav ul{display:flex;list-style:none;gap:25px}nav a{color:white;text-decoration:none;font-weight:600;font-size:1.1rem;padding:8px 12px;border-radius:6px;transition:var(--transition)}nav a:hover,nav a.active{background-color:rgba(255,255,255,0.2)}main{padding:40px 0}.section-title{font-size:1.8rem;margin-bottom:25px;color:var(--secondary-color);display:flex;align-items:center;gap:10px}.section-title i{color:var(--accent-color)}.tools-grid{display:grid;grid-template-columns:repeat(auto-fill,minmax(280px,1fr));gap:25px;margin-bottom:40px}.tool-card{background:white;border-radius:var(--border-radius);padding:25px;box-shadow:var(--box-shadow);transition:var(--transition);cursor:pointer;border:2px solid transparent}.tool-card:hover{transform:translateY(-5px);border-color:var(--primary-color)}.tool-card i{font-size:2.5rem;color:var(--primary-color);margin-bottom:15px}.tool-card h3{font-size:1.4rem;margin-bottom:10px;color:var(--dark-color)}.tool-card p{color:var(--gray-color);margin-bottom:20px}.use-tool-btn{background-color:var(--primary-color);color:white;border:none;padding:10px 20px;border-radius:6px;font-weight:600;cursor:pointer;transition:var(--transition);width:100%}.use-tool-btn:hover{background-color:var(--secondary-color)}.tool-detail{background:white;border-radius:var(--border-radius);padding:30px;box-shadow:var(--box-shadow);margin-top:30px;display:none}.tool-detail.active{display:block}.tool-header{display:flex;justify-content:space-between;align-items:center;margin-bottom:25px;padding-bottom:15px;border-bottom:2px solid #f0f2f5}.tool-header h2{font-size:1.6rem;color:var(--secondary-color)}.close-tool{background:none;border:none;font-size:1.5rem;color:var(--gray-color);cursor:pointer;transition:var(--transition)}.close-tool:hover{color:var(--warning-color)}.diff-container{display:flex;flex-direction:column;gap:20px}.diff-row{display:flex;flex-wrap:wrap;gap:20px}.diff-col{flex:1;min-width:300px}.panel-title{font-size:1.2rem;color:var(--dark-color);margin-bottom:10px;display:flex;align-items:center;gap:8px}.old-label{color:var(--old-text-color)}.new-label{color:var(--new-text-color)}textarea{width:100%;height:250px;padding:15px;border:2px solid #e0e0e0;border-radius:var(--border-radius);font-family:'Consolas','Monaco','Courier New',monospace;font-size:0.95rem;line-height:1.5;resize:vertical;transition:var(--transition)}textarea:focus{outline:none;border-color:var(--primary-color)}#old-input{border-left:4px solid var(--old-text-color)}#new-input{border-left:4px solid var(--new-text-color)}.action-bar{display:flex;gap:15px;flex-wrap:wrap;justify-content:center;background:#f8f9fa;padding:20px;border-radius:8px;border:1px solid #e0e0e0}.action-btn{padding:10px 24px;border-radius:6px;border:none;font-weight:600;cursor:pointer;transition:var(--transition);display:flex;align-items:center;gap:8px}.btn-primary{background-color:var(--primary-color);color:white}.btn-primary:hover{background-color:var(--secondary-color)}.btn-secondary{background-color:#e9ecef;color:var(--dark-color)}.btn-secondary:hover{background-color:#dee2e6}.btn-warning{background-color:var(--warning-color);color:white}.btn-warning:hover{background-color:#d1146a}.result-area{background:#fff;border:1px solid #ddd;border-radius:8px;padding:20px;min-height:200px;font-family:'Consolas','Monaco','Courier New',monospace;font-size:0.95rem;white-space:pre-wrap;word-break:break-all;line-height:1.8}.result-header{margin-bottom:15px;padding-bottom:10px;border-bottom:1px solid #eee;display:flex;justify-content:space-between;align-items:center}del{background-color:var(--diff-del-bg);color:var(--diff-del-color);text-decoration:line-through;padding:0 2px;border-radius:2px}ins{background-color:var(--diff-add-bg);color:var(--diff-add-color);text-decoration:none;padding:0 2px;border-radius:2px}.stats-bar{display:flex;gap:20px;margin-top:15px;font-size:0.9rem;color:var(--gray-color)}.stat-item{display:flex;align-items:center;gap:5px}.badge{padding:2px 8px;border-radius:4px;color:white;font-weight:bold;font-size:0.8rem}.badge-del{background-color:var(--diff-del-color)}.badge-add{background-color:var(--diff-add-color)}.badge-total{background-color:var(--primary-color)}@media (max-width:768px){.diff-row{flex-direction:column}.action-bar{flex-direction:column}.action-btn{width:100%;justify-content:center}}