* {
            margin: 0;
            padding: 0;
            box-sizing: border-box;
            font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
        }
        
        body {
            background-color: #f8f9fa;
            color: #333;
            line-height: 1.6;
        }
        
        /* Promotional Banner */
        .promo-banner {
            background: linear-gradient(to right, #3a86ff, #8338ec);
            color: white;
            text-align: center;
            padding: 12px 20px;
            font-weight: 600;
            font-size: 15px;
            position: relative;
        }
        
        .promo-banner span {
            background-color: #ff006e;
            padding: 2px 8px;
            border-radius: 12px;
            font-size: 14px;
            margin-right: 8px;
        }
        
        .close-banner {
            position: absolute;
            right: 15px;
            top: 50%;
            transform: translateY(-50%);
            cursor: pointer;
            background: rgba(255, 255, 255, 0.2);
            border-radius: 50%;
            width: 24px;
            height: 24px;
            display: flex;
            align-items: center;
            justify-content: center;
        }
        
        /* Navigation */
        nav {
            background-color: white;
            padding: 16px 20px;
            box-shadow: 0 2px 10px rgba(0, 0, 0, 0.08);
            display: flex;
            justify-content: space-between;
            align-items: center;
        }
        
        .logo {
            font-weight: 700;
            font-size: 22px;
            color: rgb(212, 65, 65) ;
            display: flex;
            align-items: center;
        }
        
        .logo i {
            margin-right: 8px;
            color: rgb(212, 65, 65);
        }
        
        .nav-links {
            display: flex;
            list-style: none;
        }
        
        .nav-links li {
            margin-left: 24px;
            position: relative;
        }
        
        .nav-links a {
            text-decoration: none;
            color: #555;
            font-weight: 500;
            font-size: 15px;
            transition: color 0.3s;
        }
        
        .nav-links a:hover {
            color: #3a86ff;
        }
        
        .nav-links .active {
            color: #3a86ff;
            font-weight: 600;
        }
        
        .nav-links .active::after {
            content: '';
            position: absolute;
            bottom: -4px;
            left: 0;
            width: 100%;
            height: 3px;
            background-color: #3a86ff;
            border-radius: 2px;
        }
        
        .nav-user {
            display: flex;
            align-items: center;
        }
        
        .user-icon {
            background-color: #f0f2f5;
            border-radius: 50%;
            width: 36px;
            height: 36px;
            display: flex;
            align-items: center;
            justify-content: center;
            margin-left: 15px;
            cursor: pointer;
        }
        
        /* Main Content */
        .container {
            max-width: 1200px;
            margin: 0 auto;
            padding: 30px 20px;
        }
        
        .header-section {
            text-align: center;
            margin-bottom: 40px;
            padding: 0 10px;
        }
        
        .header-section h1 {
            font-size: 32px;
            color: #1a1a1a;
            margin-bottom: 15px;
        }
        
        .header-section p {
            color: #666;
            font-size: 18px;
            max-width: 800px;
            margin: 0 auto 25px;
        }
        
        .highlight {
            color: #3a86ff;
            font-weight: 600;
        }
        
        /* Search Section */
        .search-section {
            background-color: white;
            border-radius: 12px;
            padding: 25px;
            box-shadow: 0 4px 12px rgba(0, 0, 0, 0.05);
            margin-bottom: 40px;
            display: flex;
            align-items: center;
            justify-content: space-between;
            flex-wrap: wrap;
        }
        
        .search-box {
            display: flex;
            align-items: center;
            flex-grow: 1;
            max-width: 500px;
            background-color: #f8f9fa;
            border-radius: 50px;
            padding: 12px 20px;
            border: 1px solid #e0e0e0;
        }
        
        .search-box i {
            color: #888;
            margin-right: 10px;
        }
        
        .search-box input {
            border: none;
            background: transparent;
            width: 100%;
            font-size: 16px;
            outline: none;
        }
        
        .category-filter {
            display: flex;
            align-items: center;
            background-color: #f8f9fa;
            border-radius: 8px;
            padding: 8px 15px;
            border: 1px solid #e0e0e0;
            margin-left: 15px;
        }
        
        .category-filter select {
            border: none;
            background: transparent;
            font-size: 15px;
            color: #555;
            outline: none;
            cursor: pointer;
        }
        
        /* IPA Chart */
        .ipa-section {
            margin-bottom: 40px;
        }
        
        .section-title {
            font-size: 22px;
            color: #1a1a1a;
            margin-bottom: 20px;
            display: flex;
            align-items: center;
        }
        
        .section-title i {
            margin-right: 10px;
            color: #3a86ff;
        }
        
        .ipa-chart {
            display: grid;
            grid-template-columns: repeat(auto-fill, minmax(160px, 1fr));
            gap: 20px;
        }
        
        .ipa-card {
            background-color: white;
            border-radius: 12px;
            padding: 25px 20px;
            text-align: center;
            box-shadow: 0 4px 8px rgba(0, 0, 0, 0.05);
            transition: transform 0.3s, box-shadow 0.3s;
            cursor: pointer;
            border: 1px solid #f0f0f0;
        }
        
        .ipa-card:hover {
            transform: translateY(-5px);
            box-shadow: 0 8px 16px rgba(0, 0, 0, 0.1);
        }
        
        .ipa-symbol {
            font-size: 42px;
            font-weight: 700;
            color: rgb(206, 64, 64);
            margin-bottom: 10px;
            font-family: 'Georgia', serif;
        }
        
        .ipa-description {
            font-size: 14px;
            color: #666;
            margin-bottom: 15px;
            min-height: 40px;
        }
        
        .practice-btn {
            background-color: #f0f7ff;
            color: #3a86ff;
            border: none;
            border-radius: 20px;
            padding: 8px 20px;
            font-weight: 600;
            font-size: 14px;
            cursor: pointer;
            transition: background-color 0.3s;
        }
        
        .practice-btn:hover {
            background-color: #e1eeff;
        }
        
        /* Footer */
        footer {
            background-color: #1a1a1a;
            color: #ccc;
            padding: 40px 20px;
            text-align: center;
            margin-top: 50px;
        }
        
        .footer-content {
            max-width: 800px;
            margin: 0 auto;
        }
        
        .footer-logo {
            font-weight: 700;
            font-size: 22px;
            color: white;
            margin-bottom: 20px;
        }
        
        .footer-links {
            display: flex;
            justify-content: center;
            flex-wrap: wrap;
            list-style: none;
            margin-bottom: 25px;
        }
        
        .footer-links li {
            margin: 0 15px 10px;
        }
        
        .footer-links a {
            color: #aaa;
            text-decoration: none;
            font-size: 15px;
        }
        
        .footer-links a:hover {
            color: white;
        }
        
        .copyright {
            font-size: 14px;
            color: #888;
        }
        
        /* Responsive */
        @media (max-width: 992px) {
            .nav-links {
                display: none;
            }
            
            .ipa-chart {
                grid-template-columns: repeat(auto-fill, minmax(140px, 1fr));
            }
        }
        
        @media (max-width: 768px) {
            .search-section {
                flex-direction: column;
                align-items: stretch;
            }
            
            .search-box {
                max-width: 100%;
                margin-bottom: 15px;
            }
            
            .category-filter {
                margin-left: 0;
                align-self: flex-start;
            }
            
            .header-section h1 {
                font-size: 28px;
            }
            
            .ipa-chart {
                grid-template-columns: repeat(auto-fill, minmax(120px, 1fr));
            }
        }
        
        @media (max-width: 576px) {
            .container {
                padding: 20px 15px;
            }
            
            .ipa-chart {
                grid-template-columns: repeat(2, 1fr);
            }
            
            .promo-banner {
                font-size: 14px;
                padding: 12px 35px 12px 15px;
            }
        }