/* https://grabient.com/_gKUgJcfRrgFkgFUg-WgLGgIfgBngFxgLLgOm?style=linearGradient&steps=6&angle=270 */

background: linear-gradient(270deg, #6b87af 0.000%, #4ec1dc 20.000%, #74e9f9 40.000%, #c2eeff 60.000%, #fccdff 80.000%, #f896ea 100.000%);

<svg xmlns="http://www.w3.org/2000/svg" width="800" height="400" viewBox="0 0 800 400" preserveAspectRatio="none">
            <!-- https://grabient.com/_gKUgJcfRrgFkgFUg-WgLGgIfgBngFxgLLgOm?style=linearGradient&steps=6&angle=270 -->
            <defs>
              <linearGradient id="gradient" x1="1.000" y1="0.500" x2="0.000" y2="0.500">
        <stop offset="0.000" stop-color="#6b87af" /><stop offset="0.200" stop-color="#4ec1dc" /><stop offset="0.400" stop-color="#74e9f9" /><stop offset="0.600" stop-color="#c2eeff" /><stop offset="0.800" stop-color="#fccdff" /><stop offset="1.000" stop-color="#f896ea" />
              </linearGradient>
            </defs>
            <rect x="0" y="0" width="800" height="400" fill="url(#gradient)" />
          </svg>

["#6b87af", "#4ec1dc", "#74e9f9", "#c2eeff", "#fccdff", "#f896ea"]

// https://grabient.com/_gKUgJcfRrgFkgFUg-WgLGgIfgBngFxgLLgOm?style=linearGradient&steps=6&angle=270
// cosine gradient palette — https://iquilezles.org/articles/palettes/
const float STEPS = 6.0;
const float ANGLE = 270.0;

vec3 palette(float t) {
    vec3 a = vec3(0.660, 0.604, -2.965);
    vec3 b = vec3(0.356, 0.340, 3.990);
    vec3 c = vec3(0.710, 0.543, 0.103);
    vec3 d = vec3(0.369, 0.715, 0.934);
    return a + b * cos(6.283185 * (c * t + d));
}

// N stops sampled from the palette, blended like the CSS gradient
vec3 stops(float t) {
    float n = STEPS - 1.0;
    float x = clamp(t, 0.0, 1.0) * n;
    return mix(palette(floor(x) / n), palette(min(floor(x) + 1.0, n) / n), fract(x));
}

void mainImage(out vec4 fragColor, in vec2 fragCoord) {
    vec2 p = fragCoord - 0.5 * iResolution.xy;
    // CSS angle: 0 = up, clockwise; span = CSS gradient-line length
    vec2 dir = vec2(sin(radians(ANGLE)), cos(radians(ANGLE)));
    float len = abs(iResolution.x * dir.x) + abs(iResolution.y * dir.y);
    float t = dot(p, dir) / len + 0.5;
    fragColor = vec4(stops(t), 1.0);
}

[
  [0.660, 0.604, -2.965],
  [0.356, 0.340, 3.990],
  [0.710, 0.543, 0.103],
  [0.369, 0.715, 0.934]
]

Gradient palette editor — #6b87af to #f896ea