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

body {
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    background-color: #525659; /* 類似 Chrome PDF 閱讀器的背景色 */
    height: 100vh;
    display: flex;
    flex-direction: column;
}

/* 頂部控制欄 */
.toolbar {
    background-color: #323639;
    color: #fff;
    padding: 10px 20px;
    display: flex;
    justify-content: space-between;
    align-items: center;
    flex-wrap: wrap;
    box-shadow: 0 2px 5px rgba(0,0,0,0.3);
    z-index: 10;
}

.control-group {
    display: flex;
    align-items: center;
    gap: 10px;
    margin: 5px 0;
}

select, button {
    background-color: #202124;
    color: #fff;
    border: 1px solid #5f6368;
    padding: 6px 12px;
    border-radius: 4px;
    cursor: pointer;
    font-size: 14px;
    transition: background 0.2s;
}

select:focus, button:hover {
    background-color: #424548;
}

#page-num-controls, #zoom-percent {
    font-size: 14px;
    min-width: 60px;
    text-align: center;
}

/* PDF 顯示區域 */
.pdf-container {
    flex: 1;
    overflow: auto; /* 允許當放大時出現捲軸 */
    display: flex;
    justify-content: center;
    align-items: flex-start;
    padding: 20px;
}

#canvas-wrapper {
    box-shadow: 0 4px 12px rgba(0,0,0,0.5);
    background-color: #fff;
    line-height: 0; /* 消除 canvas 下方微小間隙 */
}

canvas {
    display: block;
}