:root {
    --sidebar-width: 320px;
    --transition-speed: 0.3s;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
    background-color: #f0f2f5;
    color: #333;
    margin: 0;
    overflow: hidden;
}
.container {
    display: flex;
    width: 100vw;
    height: 100vh;
}
/* --- 侧边栏 --- */
.sidebar {
    width: var(--sidebar-width);
    flex-shrink: 0;
    background-color: #ffffff;
    padding: 20px;
    box-shadow: 2px 0 5px rgba(0,0,0,0.1);
    display: flex;
    flex-direction: column;
    height: 100%;
    box-sizing: border-box;
    z-index: 10;
    position: relative;
    transition: margin-left var(--transition-speed) ease;
}
#sidebarToggle {
    position: absolute; top: 50%; right: -15px; transform: translateY(-50%);
    width: 30px; height: 60px; background-color: #fff; border: 1px solid #ddd;
    border-left: none; border-radius: 0 8px 8px 0; cursor: pointer; z-index: 11;
    display: flex; align-items: center; justify-content: center;
    box-shadow: 2px 0 5px rgba(0,0,0,0.1); transition: right var(--transition-speed) ease;
}
#sidebarToggle svg { width: 24px; height: 24px; transition: transform var(--transition-speed) ease; }
body.sidebar-collapsed .sidebar { margin-left: calc(-1 * var(--sidebar-width)); }
body.sidebar-collapsed #sidebarToggle svg { transform: rotate(180deg); }
.sidebar h2 { text-align: center; margin-top: 0; color: #1a73e8; }
.control-group { margin-bottom: 20px; }
#customizationPanel { flex-grow: 1; overflow-y: hidden; display: flex; flex-direction: column; }
#customizationPanel h3 { margin-top: 0; }
#checkboxContainer { flex-grow: 1; overflow-y: auto; border: 1px solid #ddd; border-radius: 4px; padding: 10px; }
.placeholder-text { color: #888; }
.control-item { display: block; margin-bottom: 8px; cursor: pointer; }
.control-item label { margin-left: 5px; white-space: nowrap; overflow: hidden; text-overflow: ellipsis; vertical-align: middle; }

/* --- 主内容区 --- */
.main-content {
    flex-grow: 1;
    padding: 20px;
    overflow-y: auto;
    height: 100vh;
    box-sizing: border-box;
    position: relative;
}
header { text-align: center; margin-bottom: 20px; }

/* --- 虚拟化容器与卡片 (已修复) --- */
#chartsContainer {
    position: relative;
    width: 100%;
    height: 1px; /* 高度由JS设置 */
}
.chart-card {
    background: #ffffff;
    border-radius: 8px;
    cursor: zoom-in;
    padding: 20px;
    box-sizing: border-box;
    box-shadow: 0 4px 6px rgba(0,0,0,0.05);
    position: absolute;
    
    /* 最终修复方案: 分离定位 (top/left) 和动画 (transform) */
    transition: top var(--transition-speed) ease,
                left var(--transition-speed) ease,
                opacity var(--transition-speed) ease,
                transform var(--transition-speed) ease,
                box-shadow var(--transition-speed) ease;
    will-change: top, left, opacity, transform;

    /* 入场动画的初始状态 */
    opacity: 0;
    transform: translateY(20px);
}

.chart-card.visible {
    /* 入场动画的结束状态 */
    opacity: 1;
    transform: translateY(0);
}

.chart-card:hover {
    box-shadow: 0 8px 16px rgba(0,0,0,0.1);
    z-index: 1;
}
.chart-card:hover {
    box-shadow: 0 8px 16px rgba(0,0,0,0.1);
    z-index: 1;
}
.chart-card .canvas-container {
    width: 100%;
    height: 100%;
}

/* --- 模态窗口与加载动画 (无变化) --- */
.modal { position: fixed; z-index: 1000; left: 0; top: 0; width: 100%; height: 100%; background-color: rgba(0,0,0,0.6); backdrop-filter: blur(5px); display: flex; align-items: center; justify-content: center; opacity: 0; visibility: hidden; pointer-events: none; transition: opacity 0.3s ease, visibility 0.3s ease; }
.modal.is-visible { opacity: 1; visibility: visible; pointer-events: auto; }
.modal-content { background-color: #fefefe; padding: 20px; border-radius: 8px; box-shadow: 0 5px 15px rgba(0,0,0,0.3); position: relative; width: 96vw; height: 96vh; display: flex; flex-direction: column; transform: scale(0.95); transition: transform 0.3s ease; }
.modal.is-visible .modal-content { transform: scale(1); }
.close-button { color: #aaa; position: absolute; top: 10px; right: 25px; font-size: 35px; font-weight: bold; cursor: pointer; z-index: 1; }
.close-button:hover, .close-button:focus { color: #000; text-decoration: none; }
#modalChartHeader { font-size: 1.5em; font-weight: bold; margin-bottom: 5px; text-align: center; flex-shrink: 0; }
#modalChartStats { text-align: center; margin-bottom: 10px; font-size: 1.1em; color: #555; flex-shrink: 0; }
#modalChartStats span { font-weight: bold; color: #000; }
.modal-chart-wrapper { flex-grow: 1; position: relative; min-height: 0; }
#modalCanvas { position: absolute; top: 0; left: 0; width: 100%; height: 100%; }
.loader-overlay { position: absolute; top: 0; left: 0; width: 100%; height: 100%; background-color: rgba(240, 242, 245, 0.8); z-index: 2000; display: flex; flex-direction: column; justify-content: center; align-items: center; opacity: 0; visibility: hidden; pointer-events: none; transition: opacity 0.3s ease, visibility 0.3s ease; }
.loader-overlay.is-visible { opacity: 1; visibility: visible; pointer-events: auto; }
.loader-overlay p { margin-top: 20px; font-size: 1.2em; color: #333; }
.spinner { width: 60px; height: 60px; border: 5px solid #ddd; border-top: 5px solid #1a73e8; border-radius: 50%; animation: spin 1s linear infinite; }
@keyframes spin { 0% { transform: rotate(0deg); } 100% { transform: rotate(360deg); } }
/* --- Idle Loading Indicator --- */
.idle-indicator {
    position: fixed;
    top: 20px;
    right: 20px;
    width: 24px;
    height: 24px;
    border: 3px solid rgba(26, 115, 232, 0.2);
    border-top-color: #1a73e8;
    border-radius: 50%;
    z-index: 999; /* 低于模态框的 1000 */
    opacity: 0;
    visibility: hidden;
    transform: scale(0.5);
    transition: opacity 0.3s ease, visibility 0.3s ease, transform 0.3s ease;
    pointer-events: none;
    animation: spin 1s linear infinite;
}
.idle-indicator.visible {
    opacity: 1;
    visibility: visible;
    transform: scale(1);
}
/* --- Footer --- */
footer {
    position: fixed;
    bottom: 10px;
    right: 20px;
    z-index: 1001;
}

footer a {
    color: #555;
    text-decoration: none;
    font-size: 0.9em;
    transition: color 0.2s ease;
}

footer a:hover {
    color: #1a73e8;
    text-decoration: underline;
}