basic.css

.computed {
  /* Identify tests */
  --prop-001: fluid(640px 32px, 1440px 64px);
  --prop-002: fluid(640px 64px, 1440px 32px);
  --prop-003: fluid(640px -32px, 1440px 64px);
  --prop-004: fluid(1440px 64px, 640px 32px);
  --prop-005: fluid(640px 32px, 640px 32px);
  --prop-006: fluid(640px 32px, 1440px 32px);
  --prop-007: fluid(40rem 32px, 90rem 64px);
  --prop-008: fluid(640px 2rem, 1440px 4rem);
  --prop-009: fluid(40rem 2rem, 90rem 4rem);
  --prop-010: fluid(768px 24px, 1024px 32px);

  /* Nesting */
  --prop-011: calc(fluid(640px 32px, 1440px 64px) * -1);

  /* Separated list */
  --prop-012: fluid(640px 32px, 1440px 64px) fluid(640px 32px, 1440px 64px),
    fluid(640px 32px, 1440px 64px);

  /* 'viewportWidths' option */
  --prop-013: fluid(sm 32px, 2xl 64px);
  --prop-014: fluid(32px, 64px);
}

.invalid {
  /* Syntax checking */
  --prop-001: fluid();
  --prop-002: fluid(640px calc(16px * 2), 1440px 64px);
  --prop-003: fluid(640px [32px], 1440px 64px);

  /* General tests */
  --prop-004: fluid(640px 32px, 1024px 48px, 1440px 64px);
  --prop-005: fluid(-640px 32px, 1440px 64px);
  --prop-006: fluid(640px 32px, 90rem 64px);
  --prop-007: fluid(640px 32px, 1440px 4rem);
  --prop-008: fluid(640px 32px, 640px 64px);
}