Jekyll config.yml在解析块映射时未找到预期的密钥

我在命令行终端收到此错误：

在第18行第7列解析块映射时未找到预期的密钥

我的jekyll _config.yml YAML文件如下所示：

title: Oliver Williams - Portfolio
url: "http://yourdomain.com" # the base hostname & protocol for your site

# Build settings
markdown: kramdown
permalink: /:title

defaults:
  -
    scope:
      path: "" # an empty string here means all files in the project
      type: "posts" # previously `post` in Jekyll 2.2.
    values:
      layout: "post"

       -
    scope:
      path: "" # an empty string here means all files in the project
      type: "pages" 
    values:
      layout: "page"