/* 基本設定 */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

body {
    font-family: 'Microsoft JhengHei', 'PingFang TC', 'Helvetica Neue', Arial, sans-serif;
    background: #FFA042;
    min-height: 100vh;
    display: flex;
    justify-content: center;
    align-items: center;
    padding: 0;
    margin: 0;
    overflow: hidden;
    position: relative;
}

/* 載入提示 */
.loading {
    position: fixed;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    background: rgba(255, 255, 255, 0.9);
    padding: 30px 50px;
    border-radius: 10px;
    box-shadow: 0 4px 20px rgba(0, 0, 0, 0.2);
    z-index: 1000;
    font-size: 1.2rem;
    color: #2c3e50;
}

.loading.hidden {
    display: none !important;
    visibility: hidden;
    opacity: 0;
}

/* 書本容器 */
.book-container {
    position: relative;
    width: 100%;
    max-width: 1200px;
    height: 100vh;
    perspective: 1500px;
    display: flex;
    justify-content: center;
    align-items: center;
    overflow: hidden;
    padding: 20px;
    box-sizing: border-box;
}

/* PDF 頁面容器 */
.pdf-pages {
    position: relative;
    width: 100%;
    height: 100%;
    display: flex;
    justify-content: center;
    align-items: center;
}

/* PDF 頁面樣式 */
.pdf-page {
    position: absolute;
    width: auto;
    height: auto;
    max-width: 100%;
    max-height: 100%;
    background: white;
    box-shadow: none;
    border-radius: 2px;
    opacity: 0;
    transform: scale(0.75);
    transition: all 0.6s cubic-bezier(0.4, 0, 0.2, 1);
    cursor: pointer;
    overflow: hidden;
    display: flex;
    justify-content: center;
    align-items: center;
    border: none;
    outline: none;
}

.pdf-page.active {
    opacity: 1;
    transform: scale(1.15);
    z-index: 10;
    box-shadow: 0 8px 30px rgba(0, 0, 0, 0.15);
}

.pdf-page.prev-3 {
    opacity: 1;
    transform: scale(0.55) translateX(-80%);
    z-index: 2;
    pointer-events: none;
    filter: none;
}

.pdf-page.prev-2 {
    opacity: 1;
    transform: scale(0.65) translateX(-65%);
    z-index: 4;
    pointer-events: none;
    filter: none;
}

.pdf-page.prev {
    opacity: 1;
    transform: scale(0.8) translateX(-45%);
    z-index: 6;
    pointer-events: none;
    filter: none;
}

.pdf-page.next {
    opacity: 1;
    transform: scale(0.8) translateX(45%);
    z-index: 6;
    pointer-events: none;
    filter: none;
}

.pdf-page.next-2 {
    opacity: 1;
    transform: scale(0.65) translateX(65%);
    z-index: 4;
    pointer-events: none;
    filter: none;
}

.pdf-page.next-3 {
    opacity: 1;
    transform: scale(0.55) translateX(80%);
    z-index: 2;
    pointer-events: none;
    filter: none;
}

.pdf-page.hidden {
    opacity: 0;
    pointer-events: none;
    z-index: 1;
}

/* Canvas 樣式 */
.pdf-page canvas {
    display: block;
    width: auto;
    height: auto;
    max-width: 100%;
    max-height: 100%;
    object-fit: contain;
    border: none;
    outline: none;
    margin: 0;
    padding: 0;
}

/* 頁碼指示器 */
.page-indicator {
    position: fixed;
    bottom: 20px;
    right: 20px;
    background: rgba(0, 0, 0, 0.7);
    color: white;
    padding: 10px 20px;
    border-radius: 25px;
    font-size: 1rem;
    z-index: 1000;
    backdrop-filter: blur(10px);
}

/* 操作提示 */
.hint {
    position: fixed;
    bottom: 20px;
    left: 20px;
    background: #FF9224;
    color: white;
    padding: 12px 20px;
    border-radius: 25px;
    font-size: 0.9rem;
    z-index: 1000;
    box-shadow: 0 4px 15px rgba(0, 0, 0, 0.2);
    backdrop-filter: blur(10px);
}

.hint p {
    margin: 0;
}

/* 響應式設計 - 行動裝置 */
@media (max-width: 768px) {
    body {
        padding: 0;
    }
    
    .book-container {
        height: 100vh;
        padding: 10px;
        max-width: 100%;
    }
    
    .pdf-page {
        max-width: 100%;
        max-height: 100%;
    }
    
    .pdf-page.active {
        transform: scale(1);
    }
    
    /* 行動裝置只顯示前後各一頁 */
    .pdf-page.prev-3,
    .pdf-page.prev-2,
    .pdf-page.next-2,
    .pdf-page.next-3 {
        opacity: 0;
        pointer-events: none;
    }
    
    .pdf-page.prev {
        transform: scale(0.7) translateX(-30%);
    }
    
    .pdf-page.next {
        transform: scale(0.7) translateX(30%);
    }
    
    .hint {
        display: none !important;
        visibility: hidden !important;
        opacity: 0 !important;
        pointer-events: none !important;
    }
    
    .page-indicator {
        bottom: 10px;
        right: 10px;
        font-size: 0.85rem;
        padding: 6px 12px;
    }
}

/* 翻頁動畫效果 */
@keyframes flipNext {
    from {
        transform: rotateY(0deg) scale(1);
    }
    to {
        transform: rotateY(-90deg) scale(0.8);
    }
}

@keyframes flipPrev {
    from {
        transform: rotateY(0deg) scale(1);
    }
    to {
        transform: rotateY(90deg) scale(0.8);
    }
}

.pdf-page.flipping-next {
    animation: flipNext 0.6s ease-in-out;
}

.pdf-page.flipping-prev {
    animation: flipPrev 0.6s ease-in-out;
}