diff --git a/main.go b/main.go
index 49f4dee..5a92567 100644
--- a/main.go
+++ b/main.go
@@ -1,7 +1,50 @@
 package main
 
-import "fmt"
+import (
+	"fmt"
+	"net/http"
+	"time"
+)
+
+// ParseRetryAfter handles both integer seconds and HTTP-date format in Retry-After header.
+// The bug: only integer seconds are parsed; HTTP-date format is ignored, causing incorrect retry timing.
+// Fix: Detect format and parse accordingly.
+func ParseRetryAfter(header string) time.Duration {
+	if header == "" {
+		return 0
+	}
+
+	// Try parsing as integer seconds
+	var seconds int
+	if _, err := fmt.Sscanf(header, "%d", &seconds); err == nil {
+		return time.Duration(seconds) * time.Second
+	}
+
+	// Try parsing as HTTP-date format (RFC1123)
+	t, err := time.Parse(http.TimeFormat, header)
+	if err != nil {
+		// Try RFC850
+		t, err = time.Parse(time.RFC850, header)
+	}
+	if err != nil {
+		// Try ANSI C asRFC822Z
+		t, err = time.Parse(time.RFC822Z, header)
+	}
+	if err != nil {
+		return 0 // unparseable, no retry delay
+	}
+
+	delay := time.Until(t)
+	if delay < 0 {
+		return 0
+	}
+	return delay
+}
 
 func main() {
-	fmt.Println("Hello, Bounty Hunter!")
+	tests := []string{"120", "Wed, 21 Oct 2026 07:28:00 GMT", "invalid"}
+	for _, t := range tests {
+		d := ParseRetryAfter(t)
+		fmt.Printf("Retry-After: %q -> %v\n", t, d)
+	}
 }