fix(shell): prevent Rich default markdown styles from leaking background colors

CHANGELOG.md

@@ -11,6 +11,8 @@ Only write entries that are worth mentioning to users.
 
 ## Unreleased
 
+- Shell: Fix black background on inline code and code blocks in Markdown rendering — `NEUTRAL_MARKDOWN_THEME` now overrides all Rich default `markdown.*` styles to `"none"`, preventing Rich's built-in `"cyan on black"` from leaking through on non-black terminals
+
 ## 1.30.0 (2026-04-02)
 
 - Shell: Refine idle background completion auto-trigger — resumed shell sessions no longer auto-start a foreground turn from stale pending background notifications before the user sends a message, and fresh background completions now wait briefly while the user is actively typing to avoid stealing the prompt or breaking CJK IME composition

docs/en/release-notes/changelog.md

@@ -4,6 +4,8 @@ This page documents the changes in each Kimi Code CLI release.
 
 ## Unreleased
 
+- Shell: Fix black background on inline code and code blocks in Markdown rendering — `NEUTRAL_MARKDOWN_THEME` now overrides all Rich default `markdown.*` styles to `"none"`, preventing Rich's built-in `"cyan on black"` from leaking through on non-black terminals
+
 ## 1.30.0 (2026-04-02)
 
 - Shell: Refine idle background completion auto-trigger — resumed shell sessions no longer auto-start a foreground turn from stale pending background notifications before the user sends a message, and fresh background completions now wait briefly while the user is actively typing to avoid stealing the prompt or breaking CJK IME composition

docs/zh/release-notes/changelog.md

@@ -4,6 +4,8 @@
 
 ## 未发布
 
+- Shell：修复 Markdown 渲染中行内代码和代码块出现黑色背景的问题——`NEUTRAL_MARKDOWN_THEME` 现在将所有 Rich 默认的 `markdown.*` 样式覆盖为 `"none"`，防止 Rich 内置的 `"cyan on black"` 在非黑色背景终端上泄露
+
 ## 1.30.0 (2026-04-02)
 
 - Shell：细化空闲时后台完成的自动触发行为——恢复的 Shell 会话在用户发送消息前，不会因为历史遗留的后台通知而自动启动新的前景轮次；当用户正在输入时，新的后台完成事件也会短暂延后触发，避免抢占提示符或打断 CJK 输入法组合态

src/kimi_cli/ui/shell/console.py

@@ -13,6 +13,7 @@
         "markdown.paragraph": "none",
         "markdown.block_quote": "none",
         "markdown.hr": "none",
+        "markdown.list": "none",
         "markdown.item": "none",
         "markdown.item.bullet": "none",
         "markdown.item.number": "none",
@@ -25,9 +26,13 @@
         "markdown.h4": "none",
         "markdown.h5": "none",
         "markdown.h6": "none",
+        "markdown.h7": "none",
         "markdown.em": "none",
+        "markdown.emph": "none",
         "markdown.strong": "none",
         "markdown.s": "none",
+        "markdown.code": "none",
+        "markdown.code_block": "none",
         "status.spinner": "none",
     },
     inherit=True,

tests/ui/test_console_theme.py

@@ -0,0 +1,53 @@
+"""Tests for NEUTRAL_MARKDOWN_THEME style overrides."""
+
+from __future__ import annotations
+
+from kimi_cli.ui.shell.console import NEUTRAL_MARKDOWN_THEME
+
+
+class TestNeutralMarkdownThemeNoBgColor:
+    """markdown.code and markdown.code_block must not inherit Rich's default
+    black background (``"cyan on black"`` / ``"bold cyan on black"``).
+
+    Rich's built-in default theme defines::
+
+        "markdown.code":       "bold cyan on black"
+        "markdown.code_block": "cyan on black"
+
+    Because NEUTRAL_MARKDOWN_THEME uses ``inherit=True``, any style key NOT
+    explicitly listed inherits the Rich default.  If we forget to override
+    ``markdown.code`` and ``markdown.code_block``, inline code and fenced code
+    blocks will render with an opaque black background that looks wrong on
+    non-black terminals (the "black code block" bug, see issue #1681).
+    """
+
+    def test_markdown_code_has_no_background(self) -> None:
+        style = NEUTRAL_MARKDOWN_THEME.styles.get("markdown.code")
+        assert style is not None, "markdown.code must be explicitly set in NEUTRAL_MARKDOWN_THEME"
+        assert style.bgcolor is None, (
+            f"markdown.code should have no background color, got bgcolor={style.bgcolor}"
+        )
+
+    def test_markdown_code_block_has_no_background(self) -> None:
+        style = NEUTRAL_MARKDOWN_THEME.styles.get("markdown.code_block")
+        assert style is not None, (
+            "markdown.code_block must be explicitly set in NEUTRAL_MARKDOWN_THEME"
+        )
+        assert style.bgcolor is None, (
+            f"markdown.code_block should have no background color, got bgcolor={style.bgcolor}"
+        )
+
+    def test_all_markdown_styles_have_no_background(self) -> None:
+        """No markdown.* style in NEUTRAL_MARKDOWN_THEME should carry a background color.
+
+        Rich's default theme may assign background colors to markdown styles
+        (e.g. ``"cyan on black"`` for code).  Since NEUTRAL_MARKDOWN_THEME uses
+        ``inherit=True``, any key we forget to override will inherit the Rich
+        default.  This test catches that for ALL markdown styles, not just the
+        ones we know about today.
+        """
+        for name, style in NEUTRAL_MARKDOWN_THEME.styles.items():
+            if name.startswith("markdown."):
+                assert style.bgcolor is None, (
+                    f"{name} should have no background color, got bgcolor={style.bgcolor}"
+                )