diff --git a/crates/op-mcp/src/batch_design_normalize.rs b/crates/op-mcp/src/batch_design_normalize.rs
index 18719088f..eed3d10ea 100644
--- a/crates/op-mcp/src/batch_design_normalize.rs
+++ b/crates/op-mcp/src/batch_design_normalize.rs
@@ -47,6 +47,10 @@ pub(crate) fn normalize_node_shape(value: &mut serde_json::Value) {
     if let Some(padding) = obj.get_mut("padding") {
         normalize_padding(padding);
     }
+    // `effects` bodies carry REQUIRED fields (`spread` and friends). A model
+    // that omits one fails the whole node, and in the program DSL that
+    // cascades through every descendant line — see `effect_normalize`.
+    crate::effect_normalize::normalize_node_effects(obj);
     super::node_shape_defaults::normalize_text_default_bounds(obj);
     normalize_layout_keyword(obj, "justifyContent");
     normalize_layout_keyword(obj, "alignItems");
diff --git a/crates/op-mcp/src/batch_program_repair_tests.rs b/crates/op-mcp/src/batch_program_repair_tests.rs
index c27980391..9292b3cd3 100644
--- a/crates/op-mcp/src/batch_program_repair_tests.rs
+++ b/crates/op-mcp/src/batch_program_repair_tests.rs
@@ -238,3 +238,40 @@ fn children_after_a_redraft_attach_to_the_new_draft() {
         "utility must nest under the final draft"
     );
 }
+
+#[test]
+fn shadow_missing_spread_does_not_cascade_into_the_whole_card() {
+    // 2026-07-28 production log (desktop built-in agent, program-gen): a
+    // "Challenge Card" frame carried a shadow written without `spread`, serde
+    // rejected the node payload, `b9` never got a binding, and all 19
+    // following `I(b9, …)` lines died with "Insert parent not found" — the
+    // entire card vanished from the design without a visible error.
+    let mut state = sample();
+    let program = concat!(
+        "b9=I(\"n10\", {\"type\":\"frame\",\"name\":\"Challenge Card\",\"width\":320,\"height\":200,\"layout\":\"vertical\",",
+        "\"effects\":[{\"type\":\"shadow\",\"offsetX\":0,\"offsetY\":4,\"blur\":12,\"color\":\"#00000014\"}]})\n",
+        "b10=I(b9, {\"type\":\"text\",\"content\":\"Daily Challenge\",\"fontSize\":18})\n",
+        "b11=I(b9, {\"type\":\"text\",\"content\":\"3 of 5 complete\",\"fontSize\":14})"
+    );
+    let (envelope, cmd) = call_operations(&state, program);
+    assert!(envelope.get("errors").is_none(), "{envelope}");
+    let card_id = binding_id(&envelope, "b9");
+    binding_id(&envelope, "b10");
+    binding_id(&envelope, "b11");
+    assert!(state.apply(cmd.expect("command")));
+    let card = op_editor_core::walkers::find_node(state.active_children(), &NodeId::new(&card_id))
+        .expect("the card itself must land");
+    assert_eq!(
+        card.children().map(|c| c.len()).unwrap_or(0),
+        2,
+        "both descendant lines must attach to the recovered card"
+    );
+    // The authored shadow keeps its full semantics — the repair fills the
+    // missing field, it does not drop the effect.
+    let shadow = &serde_json::to_value(card).expect("card json")["effects"][0];
+    assert_eq!(shadow["type"], "shadow");
+    assert_eq!(shadow["offsetY"], 4.0);
+    assert_eq!(shadow["blur"], 12.0);
+    assert_eq!(shadow["spread"], 0.0);
+    assert_eq!(shadow["color"], "#00000014");
+}
diff --git a/crates/op-mcp/src/effect_normalize.rs b/crates/op-mcp/src/effect_normalize.rs
new file mode 100644
index 000000000..841fec84d
--- /dev/null
+++ b/crates/op-mcp/src/effect_normalize.rs
@@ -0,0 +1,263 @@
+//! Lenient normalization for a node's `effects` array.
+//!
+//! `PenEffect` is an internally-tagged enum whose bodies carry REQUIRED
+//! fields — `ShadowBody` needs `offsetX` / `offsetY` / `blur` / `spread` /
+//! `color`, `BlurBody` needs `radius` — so a model that writes a shadow and
+//! forgets one of them fails the WHOLE node, not just its decoration. In the
+//! `I(parent, node)` program DSL that failure CASCADES: the rejected node
+//! never gets a binding, so every subsequent line targeting it as a parent
+//! dies with "Insert parent not found", and an entire card silently
+//! disappears from the design. (Measured 2026-07-28: one missing `spread` on
+//! a "Challenge Card" frame took the card plus 19 descendant lines with it.)
+//!
+//! Every default injected here is the identity value for the property — the
+//! same value CSS uses when the author omits it, so filling it in cannot
+//! change how a well-formed effect renders. `color` is the one property with
+//! no identity, and its default is the neutral 25%-black every skill example
+//! already uses.
+
+use serde_json::{Map, Value};
+
+/// Neutral shadow tint used when a model omits `color`. Matches the value the
+/// skill corpus teaches, so a recovered shadow looks like an authored one.
+const DEFAULT_SHADOW_COLOR: &str = "#00000040";
+
+/// Which `PenEffect` variant an authored effect object means.
+#[derive(Clone, Copy)]
+enum EffectKind {
+    /// `inner` carries the inner-shadow / inner-glow spelling forward.
+    Shadow {
+        inner: bool,
+    },
+    Blur,
+    BackgroundBlur,
+}
+
+/// Normalize the `effects` field of a node object in place.
+///
+/// Also accepts the singular `effect` spelling: the schema field is `effects`,
+/// and serde drops the singular key without a word, so a model writing
+/// `effect` loses its shadow silently rather than loudly.
+pub fn normalize_node_effects(obj: &mut Map<String, Value>) {
+    if !obj.contains_key("effects") {
+        if let Some(value) = obj.remove("effect") {
+            obj.insert("effects".into(), value);
+        }
+    }
+    if let Some(effects) = obj.get_mut("effects") {
+        normalize_effects(effects);
+    }
+}
+
+/// Normalize an `effects` value: accept a single effect object (or a bare
+/// kind name) where the schema wants an array, then repair each entry.
+pub fn normalize_effects(value: &mut Value) {
+    match value {
+        Value::Object(_) | Value::String(_) => {
+            let single = std::mem::take(value);
+            *value = Value::Array(vec![single]);
+        }
+        Value::Array(_) => {}
+        _ => return,
+    }
+    let Value::Array(items) = value else {
+        return;
+    };
+    for item in items {
+        normalize_effect(item);
+    }
+}
+
+/// Repair one effect entry: canonicalize its `type`, then fill the required
+/// body fields its variant needs.
+fn normalize_effect(value: &mut Value) {
+    // A bare kind name (`"effects": ["shadow"]`) becomes an empty object of
+    // that kind; the body pass below fills every required field.
+    if let Value::String(name) = value {
+        let name = name.clone();
+        *value = serde_json::json!({ "type": name });
+    }
+    let Value::Object(obj) = value else {
+        return;
+    };
+    // An unrecognized kind is left exactly as authored — guessing a variant
+    // for it would invent a look the model never asked for, and the node
+    // still fails loudly rather than rendering something wrong.
+    let Some(kind) = canonical_kind(obj) else {
+        return;
+    };
+    let tag = match kind {
+        EffectKind::Shadow { .. } => "shadow",
+        EffectKind::Blur => "blur",
+        EffectKind::BackgroundBlur => "background_blur",
+    };
+    obj.insert("type".into(), Value::String(tag.into()));
+    match kind {
+        EffectKind::Shadow { inner } => {
+            if inner {
+                obj.insert("inner".into(), Value::Bool(true));
+            }
+            normalize_shadow_body(obj);
+        }
+        EffectKind::Blur | EffectKind::BackgroundBlur => normalize_blur_body(obj),
+    }
+}
+
+/// Resolve the effect's variant from its `type`, inferring one from the body
+/// shape when `type` is missing entirely.
+fn canonical_kind(obj: &Map<String, Value>) -> Option<EffectKind> {
+    let Some(raw) = obj.get("type").and_then(Value::as_str) else {
+        return infer_kind(obj);
+    };
+    let canon: String = raw
+        .chars()
+        .filter(|c| c.is_ascii_alphanumeric())
+        .map(|c| c.to_ascii_lowercase())
+        .collect();
+    // Background/backdrop blur must be tested before the plain `blur`
+    // substring, which it also contains.
+    if canon.contains("background") || canon.contains("backdrop") {
+        return Some(EffectKind::BackgroundBlur);
+    }
+    // A glow IS a shadow — zero offset, wide blur, tinted colour — and the
+    // dark style guides describe their accents in exactly those words, so
+    // models reach for the name. Routing it to `shadow` keeps the intent.
+    if canon.contains("shadow") || canon.contains("glow") {
+        return Some(EffectKind::Shadow {
+            inner: canon.contains("inner"),
+        });
+    }
+    if canon.contains("blur") {
+        return Some(EffectKind::Blur);
+    }
+    None
+}
+
+/// Infer the variant from which fields the object carries. Only fires when
+/// `type` is absent — a present-but-unknown `type` is never overridden.
+fn infer_kind(obj: &Map<String, Value>) -> Option<EffectKind> {
+    const SHADOW_ONLY: [&str; 9] = [
+        "offsetX",
+        "offsetY",
+        "offset_x",
+        "offset_y",
+        "spread",
+        "spreadRadius",
+        "dx",
+        "dy",
+        "color",
+    ];
+    if SHADOW_ONLY.iter().any(|key| obj.contains_key(*key)) {
+        return Some(EffectKind::Shadow { inner: false });
+    }
+    if obj.contains_key("radius") || obj.contains_key("blur") {
+        return Some(EffectKind::Blur);
+    }
+    None
+}
+
+/// Fill `ShadowBody`'s five required fields, accepting the aliases models
+/// borrow from CSS and Figma.
+fn normalize_shadow_body(obj: &mut Map<String, Value>) {
+    ensure_number(obj, "offsetX", &["offset_x", "offsetx", "x", "dx"], 0.0);
+    ensure_number(obj, "offsetY", &["offset_y", "offsety", "y", "dy"], 0.0);
+    ensure_number(obj, "blur", &["blurRadius", "blur_radius", "radius"], 0.0);
+    ensure_number(obj, "spread", &["spreadRadius", "spread_radius"], 0.0);
+    let mut color = None;
+    for alias in ["color", "colour", "shadowColor", "shadow_color", "fill"] {
+        let candidate = obj.remove(alias);
+        if color.is_none() {
+            color = candidate.as_ref().and_then(extract_color);
+        }
+    }
+    obj.insert(
+        "color".into(),
+        Value::String(color.unwrap_or_else(|| DEFAULT_SHADOW_COLOR.to_string())),
+    );
+    normalize_flag(obj, "inner");
+    normalize_flag(obj, "visible");
+}
+
+/// Fill `BlurBody`'s required `radius`.
+fn normalize_blur_body(obj: &mut Map<String, Value>) {
+    ensure_number(
+        obj,
+        "radius",
+        &["blur", "blurRadius", "amount", "size"],
+        0.0,
+    );
+    normalize_flag(obj, "visible");
+}
+
+/// Write `key` as a JSON number, taking the first alias present and coercing
+/// a numeric string (`"8"` / `"8px"`) on the way. Every alias is consumed so
+/// none survives as a stray key.
+fn ensure_number(obj: &mut Map<String, Value>, key: &str, aliases: &[&str], default: f64) {
+    let mut found = obj.remove(key).as_ref().and_then(as_number);
+    for alias in aliases {
+        let candidate = obj.remove(*alias);
+        if found.is_none() {
+            found = candidate.as_ref().and_then(as_number);
+        }
+    }
+    let value = found.unwrap_or(default);
+    let number = if value.fract() == 0.0 && value.is_finite() {
+        serde_json::json!(value as i64)
+    } else {
+        serde_json::json!(value)
+    };
+    obj.insert(key.into(), number);
+}
+
+/// Coerce an optional boolean field. A string `"true"` or a 0/1 number fails
+/// `Option<bool>` as hard as a missing required field does; an
+/// uninterpretable value is dropped so the schema default applies.
+fn normalize_flag(obj: &mut Map<String, Value>, key: &str) {
+    let Some(value) = obj.get(key) else {
+        return;
+    };
+    let coerced = match value {
+        Value::Bool(_) => return,
+        Value::String(text) => match text.trim().to_ascii_lowercase().as_str() {
+            "true" | "yes" | "1" => Some(true),
+            "false" | "no" | "0" => Some(false),
+            _ => None,
+        },
+        Value::Number(number) => number.as_f64().map(|n| n != 0.0),
+        _ => None,
+    };
+    match coerced {
+        Some(flag) => {
+            obj.insert(key.into(), Value::Bool(flag));
+        }
+        None => {
+            obj.remove(key);
+        }
+    }
+}
+
+fn as_number(value: &Value) -> Option<f64> {
+    match value {
+        Value::Number(number) => number.as_f64(),
+        Value::String(text) => {
+            let trimmed = text.trim().trim_end_matches("px").trim();
+            trimmed.parse::<f64>().ok()
+        }
+        _ => None,
+    }
+}
+
+/// Pull a colour string out of the shapes a model writes it in: a bare
+/// string, a fill array, or a `{type,color}` fill object.
+fn extract_color(value: &Value) -> Option<String> {
+    match value {
+        Value::String(text) if !text.trim().is_empty() => Some(text.trim().to_string()),
+        Value::Array(items) => items.iter().find_map(extract_color),
+        Value::Object(map) => map.get("color").and_then(extract_color),
+        _ => None,
+    }
+}
+
+#[cfg(test)]
+#[path = "effect_normalize_tests.rs"]
+mod tests;
diff --git a/crates/op-mcp/src/effect_normalize_tests.rs b/crates/op-mcp/src/effect_normalize_tests.rs
new file mode 100644
index 000000000..a79a2e52b
--- /dev/null
+++ b/crates/op-mcp/src/effect_normalize_tests.rs
@@ -0,0 +1,214 @@
+//! Unit tests for the `effects` normalizer. The end-to-end cascade
+//! regression (a shadow missing `spread` taking its whole subtree down) lives
+//! in `batch_program_repair_tests.rs`, where the program executor is driven.
+
+use super::*;
+
+fn normalized(node: serde_json::Value) -> serde_json::Value {
+    let mut value = node;
+    let obj = value.as_object_mut().expect("object");
+    normalize_node_effects(obj);
+    value
+}
+
+fn effect(node: &serde_json::Value) -> &serde_json::Value {
+    &node["effects"][0]
+}
+
+/// Deserialize the way the real parse path does — ids are stamped first, so
+/// these assertions test the effect repair and not the id plumbing.
+fn parse_node(
+    node: serde_json::Value,
+) -> Result<jian_ops_schema::node::PenNode, serde_json::Error> {
+    let mut value = node;
+    let mut next = 1usize;
+    crate::batch_design::ensure_node_ids(&mut value, &mut next);
+    serde_json::from_value(value)
+}
+
+#[test]
+fn shadow_missing_spread_gains_the_css_identity_default() {
+    let out = normalized(serde_json::json!({
+        "type": "frame",
+        "effects": [{ "type": "shadow", "offsetX": 0, "offsetY": 4, "blur": 12, "color": "#00000014" }],
+    }));
+    let shadow = effect(&out);
+    assert_eq!(shadow["spread"], serde_json::json!(0));
+    // The authored values survive untouched — the repair only fills the gap.
+    assert_eq!(shadow["offsetY"], serde_json::json!(4));
+    assert_eq!(shadow["blur"], serde_json::json!(12));
+    assert_eq!(shadow["color"], serde_json::json!("#00000014"));
+    let parsed = parse_node(out).expect("deserializes");
+    assert!(matches!(parsed, jian_ops_schema::node::PenNode::Frame(_)));
+}
+
+#[test]
+fn shadow_missing_every_required_field_still_deserializes() {
+    let out = normalized(serde_json::json!({
+        "type": "rectangle",
+        "width": 10,
+        "height": 10,
+        "effects": [{ "type": "shadow" }],
+    }));
+    let shadow = effect(&out);
+    for key in ["offsetX", "offsetY", "blur", "spread"] {
+        assert_eq!(
+            shadow[key],
+            serde_json::json!(0),
+            "{key} defaults to identity"
+        );
+    }
+    assert_eq!(shadow["color"], serde_json::json!(DEFAULT_SHADOW_COLOR));
+    parse_node(out).expect("deserializes");
+}
+
+#[test]
+fn shadow_aliases_and_numeric_strings_are_coerced() {
+    let out = normalized(serde_json::json!({
+        "type": "frame",
+        "effects": [{
+            "type": "drop-shadow",
+            "x": 0, "y": "8px", "blurRadius": "24", "spreadRadius": -2,
+            "colour": "#00000033",
+        }],
+    }));
+    let shadow = effect(&out);
+    assert_eq!(shadow["offsetX"], serde_json::json!(0));
+    assert_eq!(shadow["offsetY"], serde_json::json!(8));
+    assert_eq!(shadow["blur"], serde_json::json!(24));
+    assert_eq!(shadow["spread"], serde_json::json!(-2));
+    assert_eq!(shadow["color"], serde_json::json!("#00000033"));
+    // Every alias is consumed, so no stray key is left behind.
+    for alias in ["x", "y", "blurRadius", "spreadRadius", "colour"] {
+        assert!(shadow.get(alias).is_none(), "{alias} must be consumed");
+    }
+    parse_node(out).expect("deserializes");
+}
+
+#[test]
+fn shadow_color_is_read_out_of_a_fill_array() {
+    let out = normalized(serde_json::json!({
+        "type": "frame",
+        "effects": [{ "type": "shadow", "offsetY": 2, "blur": 4, "fill": [{ "type": "solid", "color": "#112233" }] }],
+    }));
+    assert_eq!(effect(&out)["color"], serde_json::json!("#112233"));
+}
+
+#[test]
+fn a_single_effect_object_is_wrapped_into_the_schema_array() {
+    let out = normalized(serde_json::json!({
+        "type": "frame",
+        "effects": { "type": "shadow", "offsetY": 4, "blur": 8 },
+    }));
+    assert!(out["effects"].is_array());
+    assert_eq!(effect(&out)["spread"], serde_json::json!(0));
+    parse_node(out).expect("deserializes");
+}
+
+#[test]
+fn singular_effect_key_is_renamed_to_the_schema_field() {
+    // `effect` is an unknown key: serde drops it without a word, so the
+    // shadow disappears silently instead of failing loudly.
+    let out = normalized(serde_json::json!({
+        "type": "frame",
+        "effect": [{ "type": "shadow", "offsetY": 4, "blur": 8 }],
+    }));
+    assert!(out.get("effect").is_none());
+    assert_eq!(effect(&out)["type"], serde_json::json!("shadow"));
+}
+
+#[test]
+fn glow_and_inner_shadow_spellings_route_to_the_shadow_variant() {
+    let out = normalized(serde_json::json!({
+        "type": "frame",
+        "effects": [
+            { "type": "glow", "blur": 20, "color": "#A855F766" },
+            { "type": "inner-shadow", "offsetY": 2, "blur": 4, "color": "#00000022" },
+        ],
+    }));
+    assert_eq!(out["effects"][0]["type"], serde_json::json!("shadow"));
+    assert_eq!(out["effects"][1]["type"], serde_json::json!("shadow"));
+    assert_eq!(out["effects"][1]["inner"], serde_json::json!(true));
+    parse_node(out).expect("deserializes");
+}
+
+#[test]
+fn blur_variants_gain_their_required_radius() {
+    let out = normalized(serde_json::json!({
+        "type": "frame",
+        "effects": [
+            { "type": "blur", "amount": 10 },
+            { "type": "backdrop-blur" },
+        ],
+    }));
+    assert_eq!(out["effects"][0]["radius"], serde_json::json!(10));
+    assert_eq!(
+        out["effects"][1]["type"],
+        serde_json::json!("background_blur")
+    );
+    assert_eq!(out["effects"][1]["radius"], serde_json::json!(0));
+    parse_node(out).expect("deserializes");
+}
+
+#[test]
+fn a_typeless_effect_body_is_classified_by_its_fields() {
+    let out = normalized(serde_json::json!({
+        "type": "frame",
+        "effects": [{ "offsetY": 4, "blur": 8, "color": "#00000020" }],
+    }));
+    assert_eq!(effect(&out)["type"], serde_json::json!("shadow"));
+    parse_node(out).expect("deserializes");
+}
+
+#[test]
+fn string_flags_are_coerced_and_junk_flags_are_dropped() {
+    let out = normalized(serde_json::json!({
+        "type": "frame",
+        "effects": [{ "type": "shadow", "offsetY": 4, "blur": 8, "visible": "true", "inner": "maybe" }],
+    }));
+    assert_eq!(effect(&out)["visible"], serde_json::json!(true));
+    assert!(effect(&out).get("inner").is_none());
+    parse_node(out).expect("deserializes");
+}
+
+#[test]
+fn an_unknown_effect_kind_is_left_exactly_as_authored() {
+    // The fallback is deliberate: inventing a variant for a name we don't
+    // recognise would paint something the model never asked for. The node
+    // still fails loudly, which is the documented tail behaviour.
+    let out = normalized(serde_json::json!({
+        "type": "frame",
+        "effects": [{ "type": "noise", "intensity": 3 }],
+    }));
+    assert_eq!(effect(&out)["type"], serde_json::json!("noise"));
+    assert_eq!(effect(&out)["intensity"], serde_json::json!(3));
+    parse_node(out).expect_err("a genuinely unknown effect still fails");
+}
+
+#[test]
+fn a_well_formed_effect_is_byte_for_byte_unchanged() {
+    let authored = serde_json::json!({
+        "type": "frame",
+        "effects": [{ "type": "shadow", "offsetX": 0, "offsetY": 4, "blur": 12, "spread": 0, "color": "#00000014" }],
+    });
+    assert_eq!(normalized(authored.clone()), authored);
+}
+
+#[test]
+fn nested_children_effects_are_normalized_too() {
+    // The node-shape pass recurses into `children`; this pins that the
+    // effects repair rides along with it.
+    let mut value = serde_json::json!({
+        "type": "frame",
+        "children": [{
+            "type": "rectangle", "width": 4, "height": 4,
+            "effects": [{ "type": "shadow", "offsetY": 4, "blur": 8 }],
+        }],
+    });
+    crate::batch_design::normalize_node_shape(&mut value);
+    assert_eq!(
+        value["children"][0]["effects"][0]["spread"],
+        serde_json::json!(0)
+    );
+    parse_node(value).expect("deserializes");
+}
diff --git a/crates/op-mcp/src/lib.rs b/crates/op-mcp/src/lib.rs
index 3db75a8a7..ef39a085b 100644
--- a/crates/op-mcp/src/lib.rs
+++ b/crates/op-mcp/src/lib.rs
@@ -92,6 +92,7 @@ pub mod document_save;
 #[cfg(test)]
 mod document_save_tests;
 pub mod editor_state_tool;
+pub mod effect_normalize;
 pub mod element_tools;
 pub mod extra_read_tools;
 #[cfg(test)]
diff --git a/crates/op-orchestrator/src/parse.rs b/crates/op-orchestrator/src/parse.rs
index e2c801ad3..0f9d59649 100644
--- a/crates/op-orchestrator/src/parse.rs
+++ b/crates/op-orchestrator/src/parse.rs
@@ -328,6 +328,11 @@ pub fn normalize_generated_node_json(value: &mut serde_json::Value) {
             }
             normalize_stroke_json(object);
             normalize_layout_enum_json(object);
+            // Shared with the program-DSL parse path: an `effects` body is
+            // missing-required-field fragile (`spread` above all), and one
+            // rejected node drops a whole card. Single-sourced in op-mcp so
+            // the two parse paths can't drift.
+            op_mcp::effect_normalize::normalize_node_effects(object);
 
             for (key, child) in object.iter_mut() {
                 // 数值型设计 token(`$type-*-size` 等)只在**数值字段**上就地解析
diff --git a/crates/op-orchestrator/src/parse_tests.rs b/crates/op-orchestrator/src/parse_tests.rs
index 6ec989e53..6d6b3409f 100644
--- a/crates/op-orchestrator/src/parse_tests.rs
+++ b/crates/op-orchestrator/src/parse_tests.rs
@@ -420,3 +420,28 @@ fn parse_nodes_ignores_draft_in_truncated_second_think() {
     // 只有 a;draft-x(在被截断的 think#2 里)不计入。
     assert_eq!(crate::cleanup::count_descendants(&nodes[0]), 1);
 }
+
+#[test]
+fn parse_nodes_tolerates_a_shadow_missing_spread() {
+    // The modify/chat flat-JSONL path shares the program-DSL病灶: `ShadowBody`
+    // 的 `spread` 是必填,模型漏写就整个节点报废。这里连子节点一起验证 ——
+    // 老逻辑下带阴影的卡片会被整张丢掉,只剩它旁边的节点。
+    let text = r##"[
+  {"type":"frame","id":"card","name":"Challenge Card","x":0,"y":0,"width":320,"height":200,
+   "effects":[{"type":"shadow","offsetX":0,"offsetY":4,"blur":12,"color":"#00000014"}]},
+  {"type":"text","id":"title","content":"Daily Challenge","fontSize":18,"_parent":"card"}
+]"##;
+
+    let nodes = parse_nodes(text).expect("a shadow missing spread must not drop the card");
+    assert_eq!(nodes.len(), 1, "the card is the only root");
+    assert_eq!(nodes[0].id_str(), "card");
+    assert_eq!(
+        crate::cleanup::count_descendants(&nodes[0]),
+        1,
+        "the child must still attach to the recovered card"
+    );
+    let effects = &serde_json::to_value(&nodes[0]).expect("card json")["effects"][0];
+    assert_eq!(effects["type"], "shadow");
+    assert_eq!(effects["spread"], 0.0);
+    assert_eq!(effects["blur"], 12.0);
+}