diff --git a/homebrew/README.md b/homebrew/README.md
index 0296f74..46a8206 100644
--- a/homebrew/README.md
+++ b/homebrew/README.md
@@ -104,7 +104,9 @@ HB_TERMINAL_WIDTH=130 ./brew-upgrade-manager.sh
 
 ## 终端主题与配色
 
-主脚本默认使用 `HB_COLOR_THEME=auto`。它会优先读取终端提供的背景信息，并通过标准 OSC 11 查询兼容 Apple Terminal、iTerm2、Termius、Kitty、WezTerm、Alacritty 等常见终端；在 SSH 中，终端客户端允许响应透传时也能识别本地背景。深色背景使用偏亮色阶，浅色背景使用更深的色阶，避免黄色、青色在白底上难以辨认。
+主脚本默认使用 `HB_COLOR_THEME=auto`，优先跟随操作系统当前的日间/夜间外观：支持 macOS、iOS/iPadOS、Windows、WSL、Android，以及使用 freedesktop Portal、GNOME、KDE、Cinnamon 或 XFCE 的 Linux 桌面。
+
+SSH 会话会直接以客户端终端背景为准，因为远端系统的日夜状态不代表 iPhone、iPad 或 Android 客户端当前主题。其他无法读取系统外观的环境（例如容器和无桌面服务器）也会继续读取 `COLORFGBG`，并通过标准 OSC 11 查询终端当前的真实背景色。Apple Terminal、iTerm2、Termius、Blink、a-Shell、iSH、Kitty、WezTerm、Alacritty 等支持相应信息的终端都能走通用回退。深色背景使用偏亮色阶，浅色背景使用更深的色阶，避免黄色、青色在白底上难以辨认。
 
 如果终端屏蔽了背景色查询，或者需要固定配色，可以手动覆盖：
 
diff --git a/homebrew/brew-upgrade-manager.sh b/homebrew/brew-upgrade-manager.sh
index 4db9eea..36cbd07 100644
--- a/homebrew/brew-upgrade-manager.sh
+++ b/homebrew/brew-upgrade-manager.sh
@@ -59,9 +59,206 @@ query_terminal_background_rgb() {
     return 1
 }
 
-detect_terminal_theme() {
+lowercase() {
+    printf '%s' "$1" | tr '[:upper:]' '[:lower:]'
+}
+
+detect_apple_appearance_theme() {
+    local appearance="" product_name=""
+
+    [[ "$(uname -s 2>/dev/null || true)" == "Darwin" ]] || return 1
+    command -v defaults >/dev/null 2>&1 || return 1
+
+    product_name="$(sw_vers -productName 2>/dev/null || true)"
+    appearance="$(defaults read -g AppleInterfaceStyle 2>/dev/null || true)"
+    if [[ -z "$appearance" && \
+        ("$product_name" == *"iPhone"* || "$product_name" == *"iOS"* || "$product_name" == *"iPad"*) ]]; then
+        appearance="$(defaults read /var/mobile/Library/Preferences/.GlobalPreferences AppleInterfaceStyle 2>/dev/null || true)"
+    fi
+    case "$appearance" in
+        Dark|dark) printf 'dark' ;;
+        Light|light) printf 'light' ;;
+        '')
+            # macOS 中该键不存在代表浅色；iOS/iPadOS 无权读取时交给终端检测。
+            if [[ "$product_name" == *"iPhone"* || "$product_name" == *"iOS"* || "$product_name" == *"iPad"* ]]; then
+                return 1
+            fi
+            printf 'light'
+            ;;
+        *) return 1 ;;
+    esac
+}
+
+detect_windows_appearance_theme() {
+    local powershell="" appearance=""
+
+    if command -v powershell.exe >/dev/null 2>&1; then
+        powershell="powershell.exe"
+    elif command -v powershell >/dev/null 2>&1; then
+        powershell="powershell"
+    fi
+    [[ -n "$powershell" ]] || return 1
+
+    # shellcheck disable=SC2016 # The single-quoted variables belong to PowerShell.
+    appearance="$($powershell -NoLogo -NoProfile -NonInteractive -Command \
+        '$theme = Get-ItemProperty -Path "HKCU:\Software\Microsoft\Windows\CurrentVersion\Themes\Personalize" -ErrorAction SilentlyContinue; if ($null -ne $theme.SystemUsesLightTheme) { [Console]::Write($theme.SystemUsesLightTheme) } elseif ($null -ne $theme.AppsUseLightTheme) { [Console]::Write($theme.AppsUseLightTheme) }' \
+        2>/dev/null || true)"
+    appearance="${appearance//$'\r'/}"
+    appearance="${appearance//[[:space:]]/}"
+    case "$appearance" in
+        0) printf 'dark' ;;
+        1) printf 'light' ;;
+        *) return 1 ;;
+    esac
+}
+
+theme_from_rgb_255() {
+    local value="$1" red green blue brightness
+
+    value="${value//,/ }"
+    read -r red green blue <<< "$value"
+    if [[ "$red" =~ ^[0-9]+$ && "$green" =~ ^[0-9]+$ && "$blue" =~ ^[0-9]+$ ]] && \
+        ((red <= 255 && green <= 255 && blue <= 255)); then
+        brightness=$(((red * 299 + green * 587 + blue * 114) / 1000))
+        if ((brightness >= 128)); then
+            printf 'light'
+        else
+            printf 'dark'
+        fi
+        return 0
+    fi
+    return 1
+}
+
+detect_linux_appearance_theme() {
+    local setting="" setting_lower="" theme_name="" theme_name_lower=""
+    local kde_reader="" background=""
+
+    # 无图形会话时，gsettings 可能只返回默认值而非真实主题；此时应让
+    # SSH/容器继续使用终端背景检测。
+    if [[ -z "${XDG_CURRENT_DESKTOP:-}" && -z "${DESKTOP_SESSION:-}" && \
+        -z "${DISPLAY:-}" && -z "${WAYLAND_DISPLAY:-}" && \
+        -z "${DBUS_SESSION_BUS_ADDRESS:-}" ]]; then
+        return 1
+    fi
+
+    # freedesktop Appearance Portal：GNOME、KDE 和多数 Wayland 桌面的统一接口。
+    if command -v gdbus >/dev/null 2>&1; then
+        setting="$(gdbus call --session \
+            --dest org.freedesktop.portal.Desktop \
+            --object-path /org/freedesktop/portal/desktop \
+            --method org.freedesktop.portal.Settings.Read \
+            org.freedesktop.appearance color-scheme 2>/dev/null || true)"
+        case "$setting" in
+            *'uint32 1'*) printf 'dark'; return ;;
+            *'uint32 2'*) printf 'light'; return ;;
+        esac
+    fi
+
+    # GNOME 42+ / Cinnamon 以及兼容 gsettings 的 GTK 桌面。
+    if command -v gsettings >/dev/null 2>&1; then
+        setting="$(gsettings get org.gnome.desktop.interface color-scheme 2>/dev/null || true)"
+        setting_lower="$(lowercase "$setting")"
+        case "$setting_lower" in
+            *prefer-dark*) printf 'dark'; return ;;
+            *prefer-light*) printf 'light'; return ;;
+        esac
+        theme_name="$(gsettings get org.gnome.desktop.interface gtk-theme 2>/dev/null || true)"
+        if [[ -z "$theme_name" ]]; then
+            theme_name="$(gsettings get org.cinnamon.desktop.interface gtk-theme 2>/dev/null || true)"
+        fi
+        if [[ -n "$theme_name" ]]; then
+            theme_name_lower="$(lowercase "$theme_name")"
+            if [[ "$theme_name_lower" == *dark* ]]; then
+                printf 'dark'
+            else
+                printf 'light'
+            fi
+            return
+        fi
+    fi
+
+    # KDE Plasma 6/5：先看配色方案名，再读取窗口背景色作判断。
+    if command -v kreadconfig6 >/dev/null 2>&1; then
+        kde_reader="kreadconfig6"
+    elif command -v kreadconfig5 >/dev/null 2>&1; then
+        kde_reader="kreadconfig5"
+    fi
+    if [[ -n "$kde_reader" ]]; then
+        theme_name="$($kde_reader --file kdeglobals --group General --key ColorScheme 2>/dev/null || true)"
+        theme_name_lower="$(lowercase "$theme_name")"
+        case "$theme_name_lower" in
+            *dark*) printf 'dark'; return ;;
+            *light*) printf 'light'; return ;;
+        esac
+        background="$($kde_reader --file kdeglobals --group 'Colors:Window' --key BackgroundNormal 2>/dev/null || true)"
+        if [[ -n "$background" ]]; then
+            theme_from_rgb_255 "$background" && return
+        fi
+    fi
+
+    # XFCE 的主题名通常直接包含 Dark；存在非 Dark 主题时按浅色处理。
+    if command -v xfconf-query >/dev/null 2>&1; then
+        theme_name="$(xfconf-query -c xsettings -p /Net/ThemeName 2>/dev/null || true)"
+        if [[ -n "$theme_name" ]]; then
+            theme_name_lower="$(lowercase "$theme_name")"
+            if [[ "$theme_name_lower" == *dark* ]]; then
+                printf 'dark'
+            else
+                printf 'light'
+            fi
+            return
+        fi
+    fi
+    return 1
+}
+
+detect_android_appearance_theme() {
+    local night_mode="" night_mode_lower=""
+
+    command -v cmd >/dev/null 2>&1 || return 1
+    night_mode="$(cmd uimode night 2>/dev/null || true)"
+    night_mode_lower="$(lowercase "$night_mode")"
+    case "$night_mode_lower" in
+        *'night mode: yes'*) printf 'dark' ;;
+        *'night mode: no'*) printf 'light' ;;
+        *) return 1 ;;
+    esac
+}
+
+detect_system_appearance_theme() {
+    local kernel
+
+    kernel="$(uname -s 2>/dev/null || true)"
+    case "$kernel" in
+        Darwin)
+            detect_apple_appearance_theme
+            ;;
+        Linux)
+            if [[ -n "${WSL_DISTRO_NAME:-}" || "$(uname -r 2>/dev/null || true)" == *[Mm]icrosoft* ]]; then
+                detect_windows_appearance_theme && return
+            fi
+            if [[ -n "${ANDROID_ROOT:-}" || -n "${TERMUX_VERSION:-}" ]]; then
+                detect_android_appearance_theme && return
+            fi
+            detect_linux_appearance_theme
+            ;;
+        MINGW*|MSYS*|CYGWIN*)
+            detect_windows_appearance_theme
+            ;;
+        FreeBSD|OpenBSD|NetBSD|DragonFly|SunOS)
+            # BSD/Unix 桌面也可能提供 freedesktop、GTK、KDE 或 XFCE 接口。
+            detect_linux_appearance_theme
+            ;;
+        *)
+            return 1
+            ;;
+    esac
+}
+
+detect_color_theme() {
     local requested="${HB_COLOR_THEME:-auto}" background_index="" rgb=""
-    local red green blue brightness
+    local red green blue brightness system_theme=""
 
     case "$requested" in
         dark|light)
@@ -72,6 +269,17 @@ detect_terminal_theme() {
         *) requested=auto ;;
     esac
 
+    # 本地运行优先跟随操作系统外观。SSH 中远端系统状态不代表客户端
+    # （例如 iOS/Android 上的 Termius），因此直接交给后面的终端背景检测。
+    if [[ -z "${SSH_TTY:-}" && -z "${SSH_CONNECTION:-}" && -z "${SSH_CLIENT:-}" ]]; then
+        system_theme="$(detect_system_appearance_theme || true)"
+        if [[ "$system_theme" == "dark" || "$system_theme" == "light" ]]; then
+            printf '%s' "$system_theme"
+            return
+        fi
+    fi
+
+    # 系统状态读取失败时，再查询终端自身提供的背景信息。
     # COLORFGBG 的最后一项是背景色索引，常见终端会主动提供。
     if [[ -n "${COLORFGBG:-}" ]]; then
         background_index="${COLORFGBG##*[;:]}"
@@ -115,20 +323,15 @@ detect_terminal_theme() {
         return
     fi
 
-    # 终端未报告背景时，用 macOS 外观作合理回退；其他平台默认深色。
-    if [[ "$(uname -s 2>/dev/null || true)" == "Darwin" ]] && \
-        [[ "$(defaults read -g AppleInterfaceStyle 2>/dev/null || true)" != "Dark" ]]; then
-        printf 'light'
-    else
-        printf 'dark'
-    fi
+    # 所有自动检测均不可用时默认深色，也可用 HB_COLOR_THEME 手动覆盖。
+    printf 'dark'
 }
 
 COLOR_THEME="none"
 if [[ -t 1 ]]; then
     COLOR_COUNT="$(tput colors 2>/dev/null || true)"
     [[ "$COLOR_COUNT" =~ ^[0-9]+$ ]] || COLOR_COUNT=8
-    COLOR_THEME="$(detect_terminal_theme)"
+    COLOR_THEME="$(detect_color_theme)"
     if ((COLOR_COUNT >= 256)) && [[ "$COLOR_THEME" == "light" ]]; then
         # 浅色背景使用更深的色阶，尤其避免亮黄、亮青在白底上失去对比。
         RED='\033[38;5;124m'