/* ============================================================
 * base.css
 * 基础样式：全屏布局、容器、背景层、canvas、加载提示、错误提示、面板遮罩
 * ============================================================ */

/* ===== 全屏无边距基础样式 ===== */
html, body {
    margin: 0;
    padding: 0;
    width: 100%;
    height: 100%;
    overflow: hidden;
    background: #000;
    color: #fff;
    font-family: system-ui, -apple-system, "Segoe UI", sans-serif;
    user-select: none;
    -webkit-user-select: none;
}
#container {
    position: fixed;
    inset: 0;
    width: 100vw;
    height: 100vh;
    background: #000;
    overflow: hidden;
}
#bgLayer {
    position: absolute;
    inset: 0;
    overflow: hidden;
    pointer-events: none;
    z-index: 0;
}
#bgImage {
    position: absolute;
    top: 50%;
    left: 50%;
    transform-origin: center center;
    max-width: none;
    max-height: none;
    will-change: transform;
}
#container canvas {
    display: block;
    width: 100% !important;
    height: 100% !important;
    position: relative;
    z-index: 1;
}

/* 加载提示 */
.loading {
    position: fixed;
    inset: 0;
    display: flex;
    align-items: center;
    justify-content: center;
    background: #000;
    color: #888;
    font-size: 14px;
    z-index: 20;
}
.loading.hidden { display: none; }

/* 错误提示 */
.error-tip {
    position: fixed;
    top: 50%;
    left: 50%;
    transform: translate(-50%,-50%);
    padding: 16px 22px;
    background: rgba(180,40,40,0.9);
    color: #fff;
    border-radius: 8px;
    font-size: 13px;
    max-width: 80vw;
    text-align: center;
    z-index: 30;
    display: none;
}
.error-tip.show { display: block; }

/* 面板遮罩 */
.panel-overlay {
    position: fixed;
    inset: 0;
    background: rgba(0,0,0,0.5);
    z-index: 40;
}
.panel-overlay.hidden { display: none; }