:root {
            --primary: #4a6fa5;
            --secondary: #6b8cbc;
            --accent: #ff6b6b;
            --dark: #2c3e50;
            --light: #f8f9fa;
            --success: #51cf66;
            --warning: #fcc419;
            --danger: #ff6b6b;
            --gray: #6c757d;
        }
        
        * {
            margin: 0;
            padding: 0;
            box-sizing: border-box;
            font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
        }
        
        body {
            background: linear-gradient(135deg, #1a2a3a, #2c3e50);
            color: var(--light);
            min-height: 100vh;
            padding: 20px;
        }
        
        .container {
            max-width: 1200px;
            margin: 0 auto;
        }
        
        header {
            text-align: center;
            margin-bottom: 30px;
            padding: 20px;
            background: rgba(255, 255, 255, 0.05);
            border-radius: 15px;
            backdrop-filter: blur(10px);
            box-shadow: 0 8px 32px rgba(0, 0, 0, 0.2);
        }
        
        h1 {
            font-size: 2.5rem;
            margin-bottom: 10px;
            background: linear-gradient(90deg, var(--accent), var(--secondary));
            -webkit-background-clip: text;
            -webkit-text-fill-color: transparent;
        }
        
        .subtitle {
            font-size: 1.2rem;
            color: var(--gray);
            margin-bottom: 20px;
        }
        
        .tool-grid {
            display: grid;
            grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
            gap: 20px;
            margin-bottom: 30px;
        }
        
        .tool-card {
            background: rgba(255, 255, 255, 0.08);
            border-radius: 12px;
            padding: 20px;
            transition: all 0.3s ease;
            cursor: pointer;
            border: 1px solid rgba(255, 255, 255, 0.1);
            backdrop-filter: blur(10px);
        }
        
        .tool-card:hover {
            transform: translateY(-5px);
            background: rgba(255, 255, 255, 0.12);
            box-shadow: 0 10px 20px rgba(0, 0, 0, 0.2);
        }
        
        .tool-card.active {
            background: rgba(74, 111, 165, 0.2);
            border-color: var(--primary);
        }
        
        .tool-icon {
            font-size: 2rem;
            margin-bottom: 15px;
            color: var(--secondary);
        }
        
        .tool-title {
            font-size: 1.3rem;
            margin-bottom: 10px;
            color: var(--light);
        }
        
        .tool-desc {
            font-size: 0.9rem;
            color: var(--gray);
            line-height: 1.5;
        }
        
        .tool-content {
            background: rgba(255, 255, 255, 0.05);
            border-radius: 15px;
            padding: 30px;
            margin-top: 20px;
            backdrop-filter: blur(10px);
            box-shadow: 0 8px 32px rgba(0, 0, 0, 0.2);
            display: none;
        }
        
        .tool-content.active {
            display: block;
            animation: fadeIn 0.5s ease;
        }
        
        @keyframes fadeIn {
            from { opacity: 0; transform: translateY(10px); }
            to { opacity: 1; transform: translateY(0); }
        }
        
        .input-group {
            margin-bottom: 20px;
        }
        
        label {
            display: block;
            margin-bottom: 8px;
            font-weight: 600;
            color: var(--light);
        }
        
        input, textarea, select {
            width: 100%;
            padding: 12px 15px;
            border-radius: 8px;
            border: 1px solid rgba(255, 255, 255, 0.2);
            background: rgba(0, 0, 0, 0.3);
            color: var(--light);
            font-size: 1rem;
            transition: all 0.3s ease;
        }
        
        input:focus, textarea:focus, select:focus {
            outline: none;
            border-color: var(--primary);
            box-shadow: 0 0 0 2px rgba(74, 111, 165, 0.3);
        }
        
        textarea {
            min-height: 120px;
            resize: vertical;
        }
        
        .btn {
            padding: 12px 25px;
            border: none;
            border-radius: 8px;
            font-size: 1rem;
            font-weight: 600;
            cursor: pointer;
            transition: all 0.3s ease;
            display: inline-flex;
            align-items: center;
            justify-content: center;
            gap: 8px;
        }
        
        .btn-primary {
            background: var(--primary);
            color: white;
        }
        
        .btn-primary:hover {
            background: var(--secondary);
            transform: translateY(-2px);
        }
        
        .btn-secondary {
            background: rgba(255, 255, 255, 0.1);
            color: var(--light);
        }
        
        .btn-secondary:hover {
            background: rgba(255, 255, 255, 0.2);
        }
        
        .btn-success {
            background: var(--success);
            color: white;
        }
        
        .btn-danger {
            background: var(--danger);
            color: white;
        }
        
        .result {
            margin-top: 20px;
            padding: 15px;
            border-radius: 8px;
            background: rgba(0, 0, 0, 0.3);
            border-left: 4px solid var(--primary);
            display: none;
        }
        
        .result-title {
            font-weight: 600;
            margin-bottom: 10px;
            color: var(--light);
        }
        
        .result-content {
            word-break: break-all;
            font-family: monospace;
            color: var(--light);
        }
        
        .file-input-wrapper {
            position: relative;
            overflow: hidden;
            display: inline-block;
            width: 100%;
        }
        
        .file-input-wrapper input[type=file] {
            position: absolute;
            left: 0;
            top: 0;
            opacity: 0;
            width: 100%;
            height: 100%;
            cursor: pointer;
        }
        
        .file-input-label {
            display: block;
            padding: 12px 15px;
            background: rgba(0, 0, 0, 0.3);
            border: 1px dashed rgba(255, 255, 255, 0.3);
            border-radius: 8px;
            text-align: center;
            cursor: pointer;
            transition: all 0.3s ease;
        }
        
        .file-input-label:hover {
            background: rgba(0, 0, 0, 0.4);
            border-color: var(--primary);
        }
        
        .flex-row {
            display: flex;
            gap: 15px;
            margin-bottom: 20px;
        }
        
        .flex-row > * {
            flex: 1;
        }
        
        .qrcode-container {
            display: flex;
            justify-content: center;
            margin: 20px 0;
        }
        
        #qrcode {
            padding: 15px;
            background: white;
            border-radius: 8px;
        }
        
        .hash-algorithms {
            display: grid;
            grid-template-columns: repeat(auto-fill, minmax(150px, 1fr));
            gap: 10px;
            margin-bottom: 20px;
        }
        
        .hash-algo {
            padding: 10px;
            background: rgba(0, 0, 0, 0.3);
            border-radius: 8px;
            text-align: center;
            cursor: pointer;
            transition: all 0.3s ease;
        }
        
        .hash-algo:hover {
            background: rgba(74, 111, 165, 0.3);
        }
        
        .hash-algo.active {
            background: var(--primary);
        }
        
        .tab-buttons {
            display: flex;
            margin-bottom: 20px;
            border-bottom: 1px solid rgba(255, 255, 255, 0.1);
        }
        
        .tab-btn {
            padding: 12px 20px;
            background: transparent;
            border: none;
            color: var(--gray);
            font-weight: 600;
            cursor: pointer;
            transition: all 0.3s ease;
            border-bottom: 2px solid transparent;
        }
        
        .tab-btn.active {
            color: var(--light);
            border-bottom: 2px solid var(--primary);
        }
        
        .tab-content {
            display: none;
        }
        
        .tab-content.active {
            display: block;
        }
        
        footer {
            text-align: center;
            margin-top: 40px;
            padding: 20px;
            color: var(--gray);
            font-size: 0.9rem;
        }
        
        .download-btn {
            margin-top: 15px;
        }
        
        .file-info {
            margin-top: 10px;
            padding: 10px;
            background: rgba(0, 0, 0, 0.2);
            border-radius: 5px;
            font-size: 0.9rem;
        }
        
        @media (max-width: 768px) {
            .tool-grid {
                grid-template-columns: 1fr;
            }
            
            .flex-row {
                flex-direction: column;
            }
        }