"""新闻文案清洗：剥离「放宽窗口」类凑数前缀。"""

from __future__ import annotations

import re

_RELAX_PREFIX = re.compile(
    r"^(?:放宽窗口|放宽至[^：:]*)\s*[:：]\s*",
    re.UNICODE,
)


def strip_relax_window_prefix(text: str) -> str:
    """去掉开头的「放宽窗口：」/「放宽至…：」前缀。"""
    raw = (text or "").strip()
    if not raw:
        return ""
    return _RELAX_PREFIX.sub("", raw, count=1).strip()