* {
            box-sizing: border-box;
        }
        .number-input, .btn {
            box-sizing: border-box;
            width: 100%;
        }
        .container {
            max-width: 1200px;
            margin: 0 auto;
            padding: 20px;
        }
  .main-container h1 {
  color: #1f2937;
  font-size: 2rem;
  margin-bottom: 2rem;
  text-align: center;
}
        .main-container {
            display: flex;
            flex-direction: column;
            gap: 30px;
        }
        .left-section, .explanation-section, .svg-container {
            background: white;
            padding: 25px;
            border-radius: 15px;
            box-shadow: 0 4px 6px rgba(0, 0, 0, 0.1);
        }
        .left-section {
            background: #fafafa;
            border: 2px solid #e5e7eb;
            display: flex;
            justify-content: center;
        }
        .input-group {
            display: flex;
            gap: 30px;
            align-items: flex-start;
            max-width: 800px;
            width: 100%;
        }
        #numbers-container {
            display: flex;
            flex-direction: column;
            gap: 10px;
            flex: 1;
            max-width: 400px;
        }
        .number-input {
            padding: 12px 15px;
            font-size: 18px;
            border: 2px solid #e0e0e0;
            border-radius: 8px;
            width: 100%;
            text-align: right;
            transition: border-color 0.3s ease;
        }
        .number-input:focus {
            border-color: #3498db;
            outline: none;
            box-shadow: 0 0 0 3px rgba(52, 152, 219, 0.2);
        }
        .buttons-group {
            display: flex;
            flex-direction: column;
            gap: 10px;
            width: 140px;
        }
        .btn {
            background: #3498db;
            color: white;
            border: none;
            padding: 12px 25px;
            border-radius: 8px;
            cursor: pointer;
            font-size: 16px;
            font-weight: 600;
            transition: all 0.3s ease;
        }
        .btn:hover {
            background: #2980b9;
            transform: translateY(-2px);
        }
        .bottom-sections {
            display: flex;
            flex-direction: column;
            gap: 30px;
        }
        .svg-container {
            background: white;
            border-radius: 15px;
            box-shadow: 0 4px 6px rgba(0, 0, 0, 0.1);
            height: auto;
        }
        #animationSvg {
            width: 100%;
            height: auto;
            display: block;
        }
        .explanation-section {
            flex: 1;
        }
        .step-explanation {
            padding: 15px;
            margin: 10px 0;
            border-left: 4px solid #3498db;
            background: #f8f9fa;
            border-radius: 0 8px 8px 0;
            transition: all 0.3s ease;
        }
        .step-explanation.active {
            border-left-color: #e67e22;
            background: #fff3e0;
            box-shadow: 0 2px 5px rgba(0,0,0,0.1);
        }
        .step-title {
            font-size: 18px;
            margin-bottom: 8px;
            color: #2c3e50;
        }
        .step-detail {
            font-size: 16px;
            color: #666;
            line-height: 1.5;
            padding-left: 15px;
            border-left: 2px solid #eee;
            margin-top: 8px;
        }
        .hidden {
            display: none !important;
        }
        .multiplication-grid {
            display: grid;
            grid-template-columns: auto 1fr;
            gap: 10px;
            align-items: center;
            margin-top: 10px;
        }
        .carry-number {
            color: red;
            font-size: 0.8em;
            position: relative;
            top: -0.5em;
        }
        @media (min-width: 768px) {
            .bottom-sections {
                flex-direction: row;
            }
            .svg-container {
                flex: 35;
                min-height: 400px;
            }
            .explanation-section {
                flex: 65;
                min-height: 400px;
            }
        }
        @media (max-width: 767px) {
            .container {
                padding: 10px;
            }
            .input-group {
                flex-direction: column;
                align-items: center;
            }
            #numbers-container {
                width: 100%;
                max-width: 300px;
            }
            .buttons-group {
                width: 100%;
                max-width: 300px;
            }
        }

.rastgele-btn {
    background-color: white !important;
    color: black !important;
    border: 1px solid #ccc !important;
}

.rastgele-btn:hover {
    background-color: #f8f9fa !important;
}

        #sayfam {
            display: none;
        }

        .gizli {
            display: block;
        }

        @media only screen and (max-width: 768px) {
            #sayfam {
                display: block;
            }

            .gizli {
                display: none;
            }
        }

        body {
            max-width: 990px;
            /* veya istediğiniz genişlik */
            background: #f8f8ff;
            border-radius: 1px;
            border: 1px solid #2A7595;
            margin: 0px auto 10px auto;
            min-height: 200px;
            width: 990px;
        }

        @media screen and (max-width: 768px) {
            body {
                max-width: 100%;
                background: #E8E8E8;
                border-radius: 10px;
                margin: 1px auto 10px auto;
                min-height: 200px;
                width: auto;
            }

            #sayfam {
                background: #E8E8E8;
                margin: 1px auto 10px auto;
                width: auto;
                padding: 10px 2px 0px 1px;
            }
        }