{
  "schemaVersion": 1,
  "sourceKind": "authored-spec",
  "provenance": "authored-in-repo",
  "specFile": "spec/移动端规格.md",
  "specSection": "40 · 遮罩层 Overlay",
  "confidence": "high",
  "slug": "mobile-overlay",
  "name": "遮罩层 Overlay",
  "semanticTypeCandidates": [
    "overlay",
    "scrim",
    "mask"
  ],
  "variantDimensions": [
    {
      "name": "tone",
      "values": [
        "default",
        "strong",
        "blur"
      ]
    },
    {
      "name": "contained",
      "values": [
        "false",
        "true"
      ]
    }
  ],
  "representativeVariants": [
    {
      "tone": "default",
      "contained": "false",
      "label": "基础全屏遮罩"
    },
    {
      "tone": "strong",
      "contained": "false",
      "label": "浓遮罩（需要专注的确认）"
    },
    {
      "tone": "blur",
      "contained": "true",
      "label": "模糊 + 局部（卡内加载态）"
    }
  ],
  "anatomy": {
    "overlay": "根元素，定位容器与开合开关；role=\"presentation\"，自身不承担语义",
    "scrim": "遮罩面（原生 button），aria-hidden=\"true\" 且 tabindex=\"-1\" —— 可点但不进键盘序列",
    "content": "内容容器（默认插槽落点），语义由宿主决定（对话框给 role=\"dialog\"、面板给 role=\"region\"）"
  },
  "structurePatterns": {
    "tone": "default 普通 / strong 浓遮罩 / blur 叠加背景模糊",
    "contained": "false 固定全屏 / true 绝对定位填充最近的定位祖先",
    "状态类": "is-open 展开（视觉与手势同时让开）"
  },
  "usageHints": [
    "浮层的基座：在内容之上盖一层半透明遮罩，让下层内容退到背后（对话框、抽屉、图片预览、卡片加载态）",
    "与弹出层的分工：弹出层是能独立使用的完整浮层，遮罩层只提供「变暗 + 拦手势 + 承载任意内容」",
    "触屏上遮罩必须真的吃掉触摸事件，否则惯性滚动会从遮罩底下穿过去把下层页面滚走",
    "遮罩关闭的键盘路径不落在遮罩上：遮罩显式 tabindex=\"-1\"，键盘用户靠内容里的关闭按钮",
    "lockScroll=true 时组件只在根上写 data-lock-scroll 标记，实际的 overflow: hidden 由宿主执行"
  ],
  "doNotInvent": [
    "焦点陷阱（focus trap）与初始焦点策略",
    "多层遮罩的层叠顺序管理",
    "手势下滑关闭与拖拽阻尼",
    "滚动锁定的实现细节（组件只写标记，改 DOM 由宿主做）"
  ],
  "unknowns": [
    "blur 档在低端机上的性能开销是否可接受（未做降级探测）",
    "contained=true 时是否应自动为宿主补 position: relative",
    "是否要支持「点遮罩不关但双击关」这类折中策略"
  ],
  "interaction": [
    "一次轻点遮罩即关闭；closeOnMask=false 时不关闭",
    "遮罩显式 tabindex=\"-1\"，不进键盘序列；键盘用户靠内容里的关闭按钮与 Esc 关闭",
    "开合动效 240ms（--kole-m-duration-slide），prefers-reduced-motion 下瞬时切换",
    "contained=true 时要求宿主祖先链上存在定位元素，否则会向上找到视口"
  ],
  "accessibility": [
    "遮罩面 aria-hidden=\"true\"（纯装饰）且 tabindex=\"-1\"（不进键盘序列）",
    "根 role=\"presentation\"：容器本身不产生语义，避免读屏把它当成一个空的分组",
    "内容语义完全由宿主提供：焦点陷阱、aria-modal、初始焦点与关闭后焦点归还都属于宿主职责",
    "遮罩关闭不依赖颜色：开合只改透明度且有 240ms 过渡"
  ],
  "api": {
    "source": "implementation",
    "note": "props / events / slots 为 6 端实现的公共接口（说明文字取自规格对应小节）。字段名与各端源码逐名核对：node tools/verify-mobile-docs.mjs",
    "requiredNote": "「必传」按严格定义：实现里**没有默认值**时才为 Y（本门禁逐条核对 props 与各端源码的默认值，防止契约与实现脱节）。",
    "props": [
      {
        "name": "open",
        "type": "boolean",
        "default": "false",
        "desc": "状态 open：展开且拦下所有手势（规格 §40.4）",
        "required": false
      },
      {
        "name": "contained",
        "type": "boolean",
        "default": "false",
        "desc": "变体 contained：绝对定位填充最近的定位祖先，做卡内局部遮罩（规格 §40.3）",
        "required": false
      },
      {
        "name": "tone",
        "type": "'default' | 'strong' | 'blur'",
        "default": "'default'",
        "desc": "变体 tone：遮罩浓度与质感（规格 §40.3）",
        "required": false
      },
      {
        "name": "lockScroll",
        "type": "boolean",
        "default": "true",
        "desc": "是否锁住下层滚动；组件只写 data-lock-scroll 标记（规格 §40.5）",
        "required": false
      },
      {
        "name": "closeOnMask",
        "type": "boolean",
        "default": "true",
        "desc": "遮罩点击是否关闭；表单类内容通常设为 false（规格 §40.5）",
        "required": false
      }
    ],
    "events": [
      {
        "name": "close",
        "params": "—",
        "desc": "点击遮罩（closeOnMask=true 时）触发；是否收起由宿主决定（规格 §40.5）"
      }
    ],
    "slots": [
      {
        "name": "default",
        "desc": "遮罩之上的内容；语义（role / aria-modal）由宿主提供（规格 §40.2 content）"
      }
    ]
  },
  "variantClasses": {
    "tone": {
      "default": [
        ".kole-m-overlay--default"
      ],
      "strong": [
        ".kole-m-overlay--strong"
      ],
      "blur": [
        ".kole-m-overlay--blur"
      ]
    },
    "contained": {
      "false": [],
      "true": [
        ".kole-m-overlay--contained"
      ]
    }
  },
  "demos": [
    {
      "id": "basic",
      "group": "01 组件类型",
      "title": "基础遮罩",
      "desc": "tone=default：遮罩本身不带语义，role 与标题由内容自己给；一次轻点遮罩即关闭。",
      "variant": "tone=default"
    },
    {
      "id": "strong",
      "group": "01 组件类型",
      "title": "浓遮罩",
      "desc": "tone=strong：遮挡更强，用于需要专注的确认；默认展开以便直接对照两层浓度。",
      "variant": "tone=strong"
    },
    {
      "id": "blur",
      "group": "01 组件类型",
      "title": "模糊遮罩",
      "desc": "tone=blur：背景内容做 backdrop 模糊，用于图片预览；模糊只影响遮罩下方，内容卡片保持清晰。",
      "variant": "tone=blur"
    },
    {
      "id": "contained",
      "group": "02 组件状态",
      "title": "局部遮罩",
      "desc": "contained=true：绝对定位填充最近的定位祖先，只遮住一张卡，页面其它区域仍可操作。",
      "variant": "contained=true"
    },
    {
      "id": "keep-open",
      "group": "02 组件状态",
      "title": "遮罩不关闭",
      "desc": "closeOnMask=false：误触遮罩不收起；填到一半的表单不该因为一次误触就丢弃已填数据。",
      "variant": "closeOnMask=false"
    }
  ],
  "related": [
    {
      "slug": "mobile-popup",
      "why": "需要带方向位移与标题栏的完整浮层时用弹出层，遮罩层只做底座不负责内容结构"
    },
    {
      "slug": "mobile-dialog",
      "why": "需要确认或输入的中断式浮层用对话框，它自己已含遮罩与按钮组"
    },
    {
      "slug": "mobile-loading",
      "why": "局部加载态需要转圈图标时用加载组件，遮罩层只提供变暗与拦手势"
    }
  ]
}