css: Use SCSS nesting for `.screen .line`.
css: Use SCSS nesting for `.screen .line`.

zulip/zulip,punchagan/zulip,showell/zulip,hackerkid/zulip,hackerkid/zulip,rht/zulip,brainwane/zulip,showell/zulip,kou/zulip,showell/zulip,andersk/zulip,andersk/zulip,brainwane/zulip,hackerkid/zulip,showell/zulip,kou/zulip,brainwane/zulip,eeshangarg/zulip,kou/zulip,punchagan/zulip,eeshangarg/zulip,eeshangarg/zulip,brainwane/zulip,kou/zulip,showell/zulip,brainwane/zulip,zulip/zulip,andersk/zulip,eeshangarg/zulip,rht/zulip,punchagan/zulip,rht/zulip,andersk/zulip,rht/zulip,andersk/zulip,eeshangarg/zulip,punchagan/zulip,hackerkid/zulip,rht/zulip,zulip/zulip,punchagan/zulip,zulip/zulip,showell/zulip,brainwane/zulip,eeshangarg/zulip,showell/zulip,punchagan/zulip,eeshangarg/zulip,rht/zulip,rht/zulip,zulip/zulip,zulip/zulip,hackerkid/zulip,kou/zulip,kou/zulip,hackerkid/zulip,andersk/zulip,andersk/zulip,kou/zulip,brainwane/zulip,punchagan/zulip,zulip/zulip,hackerkid/zulip