:root {
    --background-color: #f0f2f5;
    --container-bg: #ffffff;
    --text-color: #333;
    --border-color: #ddd;
    --accent-color: #007bff;
    --correct-color: #28a745;
    --incorrect-color: #dc3545;
}

body {
    font-family: 'Poppins', -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
    background-color: var(--background-color);
    margin: 0;
    padding: 20px;
    color: var(--text-color);
}

/* --- ANA YENİ LAYOUT --- */
.main-layout {
    display: flex;
    justify-content: stretch;
    align-items: flex-start;
    width: 100vw;
    min-height: 100vh;
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

.side-column {
    background-color: #ececec;
    width: 305px;
    min-height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.3rem;
    font-weight: 600;
    color: #888;
    position: sticky;
    top: 0;
    z-index: 10;
    box-sizing: border-box;
}

.left-column {
    border-right: 1px solid #ddd;
}

.right-column {
    border-left: 1px solid #ddd;
}

.app-container {
    flex-grow: 1;
    width: 100%;
    min-height: 100vh;
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

/* --- ESKİ LAYOUT KALDIRILDI (ad-sidebar vs.) --- */

/* --- UYGULAMA İÇERİĞİ --- */
.screen {
    width: 100%;
    min-height: 80vh;
    display: flex;
    justify-content: center;
    align-items: center;
}
.lobby-container {
    text-align: center;
    padding: 50px;
    background-color: var(--container-bg);
    border-radius: 16px;
    box-shadow: 0 8px 30px rgba(0, 0, 0, 0.08);
    width: 100%;
    box-sizing: border-box;
}
.lobby-container h1 { font-size: 2rem; margin-bottom: 15px; }
.lobby-container p { margin-bottom: 25px; }
.quiz-selection-area { width: 100%; text-align: left; }
#quiz-search-input { width: 100%; padding: 12px; font-size: 1rem; border: 1px solid #ccc; border-radius: 8px; margin-bottom: 15px; box-sizing: border-box; }
#quiz-list-container { max-height: 40vh; overflow-y: auto; border: 1px solid #eee; border-radius: 8px; padding: 10px; }
.quiz-list-item { padding: 15px; background-color: #f8f9fa; border-radius: 6px; margin-bottom: 8px; cursor: pointer; transition: background-color 0.2s; font-weight: 600; }
.quiz-list-item:hover { background-color: #e9ecef; }
.competition-container { display: none; width: 100%; background-color: var(--container-bg); border-radius: 16px; box-shadow: 0 8px 30px rgba(0, 0, 0, 0.08); }
.quiz-panel { width: 100%; margin: 0 auto; padding: 0; display: flex; flex-direction: column; min-height: 80vh; }
.quiz-header { display: flex; justify-content: space-between; align-items: center; padding: 20px 30px; background-color: #f8f9fa; border-bottom: 1px solid var(--border-color); border-radius: 16px 16px 0 0; }
.quiz-title { font-size: 1.2rem; font-weight: 600; white-space: nowrap; overflow: hidden; text-overflow: ellipsis; flex-grow: 1; }
.solo-score-display { font-size: 1.5rem; font-weight: bold; margin-left: 20px; }
.question-area { flex-grow: 1; display: flex; flex-direction: column; justify-content: center; padding: 30px; overflow-y: auto; }
.question-area h3 { font-size: clamp(1.2rem, 2.2vw, 1.8rem); margin-bottom: 30px; text-align: center; line-height: 1.4; }
.options-grid { display: grid; grid-template-columns: 1fr; gap: 15px; }
.option-btn { width: 100%; padding: 15px; font-size: 1rem; border: 1px solid var(--border-color); border-radius: 8px; background-color: var(--container-bg); cursor: pointer; transition: background-color 0.2s, transform 0.1s; text-align: left; }
.option-btn:hover:not(:disabled) { background-color: #f5f5f5; }
.option-btn.correct { background-color: var(--correct-color); color: white; border-color: var(--correct-color); }
.option-btn.incorrect { background-color: var(--incorrect-color); color: white; border-color: var(--incorrect-color); }
.option-btn:disabled { cursor: not-allowed; opacity: 0.7; }
.explanation-area { margin-top: 20px; padding: 15px; background-color: #f8f9fa; border-radius: 8px; border: 1px solid var(--border-color); display: none; }
.next-question-btn { display: none; margin: 20px auto 0; padding: 12px 30px; font-size: 1.1rem; font-weight: bold; color: white; background-color: var(--accent-color); border: none; border-radius: 8px; cursor: pointer; }
.quiz-footer { text-align: center; font-size: 0.9rem; color: #888; padding: 20px; flex-shrink: 0; }
#mobile-ad-container { display: none; }

/* --- MOBİL UYUMLULUK --- */
@media (max-width: 1200px) {
    .ad-sidebar-right { display: none; }
}
@media (max-width: 992px) {
    body { padding: 0; }
    .side-column { display: none; }
    .main-layout { flex-direction: column; }
    .app-container { max-width: 100%; }
    .lobby-container, .competition-container {
        width: 100%; max-width: 100%; height: 100vh; border-radius: 0; box-shadow: none; padding: 20px;
    }
    .quiz-panel, .screen { height: 100%; }
    .question-area { padding: 20px 15px 80px 15px; }
    #mobile-ad-container { display: flex; position: fixed; bottom: 0; left: 0; width: 100%; height: 60px; background-color: #e9ecef; border-top: 1px solid var(--border-color); z-index: 1000; justify-content: center; align-items: center; }
}