body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, sans-serif;
    background-color: #f4f7f9;
    color: #333;
    display: flex;
    justify-content: center;
    padding: 20px;
    min-height: 100vh;
}

.container {
    background-color: #ffffff;
    padding: 30px 40px;
    border-radius: 12px;
    box-shadow: 0 8px 25px rgba(0, 0, 0, 0.1);
    width: 100%;
    max-width: 750px;
}

h1 {
    text-align: center;
    color: #2c3e50;
    margin-bottom: 10px;
}

.description {
    text-align: center;
    color: #7f8c8d;
    font-size: 16px;
    margin-bottom: 30px;
}

/* Sekmeli Navigasyon Stilleri */
.tab-nav {
    display: flex;
    border-bottom: 2px solid #dfe4ea;
    margin-bottom: 25px;
}

.tab-link {
    padding: 12px 20px;
    cursor: pointer;
    border: none;
    background-color: transparent;
    font-size: 16px;
    font-weight: 600;
    color: #7f8c8d;
    position: relative;
    top: 2px;
    transition: all 0.3s ease;
}

.tab-link.active {
    color: #007bff;
    border-bottom: 2px solid #007bff;
}

/* Sekme İçerik Stilleri */
.tab-content {
    display: none;
    animation: fadeIn 0.5s;
}

.tab-content.active {
    display: block;
}

@keyframes fadeIn {
    from { opacity: 0; }
    to { opacity: 1; }
}

/* Form Elemanları */
.checkbox-group {
    background-color: #f8f9fa;
    border: 1px solid #e9ecef;
    border-radius: 8px;
    padding: 20px;
    margin-top: 15px;
    margin-bottom: 25px;
}

.checkbox-group label {
    display: block;
    margin-bottom: 12px;
    font-size: 15px;
    cursor: pointer;
}

.checkbox-group label:last-child {
    margin-bottom: 0;
}

input[type="checkbox"] {
    margin-right: 10px;
    transform: scale(1.2);
}

button[type="submit"] {
    width: 100%;
    padding: 14px;
    background-color: #007bff;
    color: white;
    border: none;
    border-radius: 6px;
    font-size: 18px;
    font-weight: bold;
    cursor: pointer;
    transition: background-color 0.3s;
}

button[type="submit"]:hover {
    background-color: #0056b3;
}

/* Sonuç Kutusu */
.result-box {
    margin-top: 25px;
    padding: 20px;
    border-radius: 8px;
    background-color: #e9f7fd;
    border-left: 5px solid #007bff;
    animation: fadeIn 0.5s;
}

.result-box.hidden {
    display: none;
}

.result-box h4 {
    margin-top: 0;
    color: #0056b3;
}

/* Açıklama Butonu Stilleri */
.explanation-button-container {
    margin-top: 15px;
    text-align: right;
}

.show-explanation-btn {
    background-color: #6c757d;
    color: #ffffff;
    border: none;
    padding: 8px 16px;
    font-size: 14px;
    border-radius: 5px;
    cursor: pointer;
    transition: background-color 0.3s;
}

.show-explanation-btn:hover {
    background-color: #5a6268;
}

/* Modal Stilleri (Daha önceki projeden tanıdık) */
.modal {
    display: none; 
    position: fixed; 
    z-index: 1000;
    left: 0;
    top: 0;
    width: 100%;
    height: 100%;
    overflow: auto; 
    background-color: rgba(0, 0, 0, 0.6);
}

.modal-content {
    background-color: #fefefe;
    margin: 15% auto;
    padding: 25px 35px;
    border-radius: 10px;
    box-shadow: 0 5px 25px rgba(0, 0, 0, 0.25);
    position: relative;
    width: 85%;
    max-width: 600px;
    animation: fadeIn 0.4s;
}

/* Kapatma butonu, animasyon vs. önceki CSS'te mevcut olduğundan tekrar eklemeye gerek yok */
/* Sadece modal içeriğindeki metin için stil ekleyelim */
#modal-title {
    color: #0056b3;
    margin-top: 0;
    border-bottom: 1px solid #ddd;
    padding-bottom: 10px;
}

#modal-text {
    font-size: 15px;
    line-height: 1.6;
    text-align: justify;
}