Update app.py

app.py

@@ -22,6 +22,15 @@ try:
 except Exception:
     HAS_PYGMT = False
 
+# ---- 自動抓取 PyGMT 所需的海岸線/國界資料（GSHHG/DCW） ----
+if 'HAS_PYGMT' in globals() and HAS_PYGMT:
+    try:
+        pygmt.which("@gshhg", download=True)
+        pygmt.which("@dcw", download=True)
+    except Exception:
+        # 若下載失敗就靜默忽略，之後會走 matplotlib 備援
+        pass
+
 # -----------------------------
 # 台北時區 (UTC+8)
 # -----------------------------
@@ -187,12 +196,10 @@ def plot_map_path(df):
     if df.empty:
         return None
 
-    # 先清一下 NaN
     d = df.dropna(subset=["Lon", "Lat"]).copy()
     if d.empty:
         return None
 
-    # 數值化
     d["Magnitude"] = pd.to_numeric(d["Magnitude"], errors="coerce").fillna(0).clip(lower=0)
     d["Depth_km"]  = pd.to_numeric(d["Depth_km"], errors="coerce").fillna(0)
 
@@ -204,8 +211,9 @@ def plot_map_path(df):
         fig = pygmt.Figure()
         fig.coast(
             region=region, projection="M12c",
-            land="lightgray", water="white",
-            shorelines="0.5p,black", borders="1/0.6p,black",
+            resolution="i",                 # 中解析度海岸線
+            land="lightgray", water="lightblue",
+            shorelines="0.8p,black", borders="1/0.6p,black",
             frame=["WSen", "xaf", "yaf"]
         )
         fig.plot(
@@ -220,7 +228,7 @@ def plot_map_path(df):
         fig.savefig(outpath, dpi=220)
         return outpath
 
-    # --- Matplotlib 備援（自動範圍 + 簡易海岸線無法；以格線為主） ---
+    # --- Matplotlib 備援（自動範圍，無海岸線） ---
     region = _auto_region_from_df(d, pad=0.5)
     lon_min, lon_max, lat_min, lat_max = region