:root {
            --primary-color: #0984e3;
            --bg-color: #f0f2f5;
        }
 body {
            font-family: 'Hind Siliguri', sans-serif;
            background-color: var(--bg-color);
            margin: 0;
            padding: 20px;
            color: #2d3436;
        }

        .container {
            max-width: 850px;
            margin: auto;
        }

        /* হেডার স্টাইল */
        .header {
            background: var(--primary-color);
            color: white;
            text-align: center;
            padding: 30px 20px;
            border-radius: 20px;
            margin-bottom: 30px;
            position: relative;
            box-shadow: 0 10px 20px rgba(9, 132, 227, 0.2);
        }

        .back-btn {
            position: absolute;
            left: 20px;
            top: 50%;
            transform: translateY(-50%);
            color: white;
            text-decoration: none;
            background: rgba(255, 255, 255, 0.2);
            padding: 8px 15px;
            border-radius: 12px;
            font-size: 14px;
            font-weight: bold;
            transition: 0.3s;
            backdrop-filter: blur(5px);
        }

        .back-btn:hover {
            background: white;
            color: var(--primary-color);
        }

        .header h1 {
            margin: 0;
            font-size: 24px;
        }

        .header p {
            margin: 5px 0 0;
            opacity: 0.9;
            font-size: 16px;
        }

        /* প্রশ্ন কার্ড স্টাইল */
        .qa-card {
            background: white;
            margin-bottom: 15px;
            border-radius: 15px;
            overflow: hidden;
            box-shadow: 0 4px 6px rgba(0, 0, 0, 0.05);
            border: 1px solid #e1e4e8;
            transition: 0.3s;
        }

        .qa-card:hover {
            transform: translateY(-2px);
            box-shadow: 0 6px 12px rgba(0, 0, 0, 0.1);
        }

        .question-btn {
            width: 100%;
            padding: 20px;
            background: white;
            border: none;
            display: flex;
            justify-content: space-between;
            align-items: center;
            cursor: pointer;
            text-align: left;
            font-size: 18px;
            font-weight: 700;
            color: #2d3436;
            outline: none;
        }

        .question-btn i {
            width: 25px;
            height: 25px;
            background: var(--primary-color);
            color: white;
            border-radius: 50%;
            display: flex;
            align-items: center;
            justify-content: center;
            font-style: normal;
            transition: 0.3s;
        }

        .answer-panel {
            max-height: 0;
            overflow: hidden;
            transition: max-height 0.4s ease-out;
            background: #fdfdfd;
        }

        .answer-content {
            padding: 20px;
            border-top: 1px solid #f1f1f1;
            line-height: 1.8;
            color: #4b4b4b;
            border-left: 5px solid var(--primary-color);
            font-size: 16px;
        }

        .active i {
            transform: rotate(45deg);
            background: #ff7675;
        }

        footer {
            text-align: center;
            margin-top: 40px;
            color: #636e72;
            font-size: 14px;
        }