Gradient palette editor — #492359 to #0a3bb3

/* https://grabient.com/_gGygEKgFfgG4gCHgF9gLcgTsgMrgK4gHBgD7?style=linearGradient&steps=8&angle=180 */

background: linear-gradient(180deg, #492359 0.000%, #922c18 14.286%, #cc5000 28.571%, #df660a 42.857%, #c35544 57.143%, #843088 71.429%, #3d22b5 85.714%, #0a3bb3 100.000%);

<svg xmlns="http://www.w3.org/2000/svg" width="800" height="400" viewBox="0 0 800 400" preserveAspectRatio="none">
            <!-- https://grabient.com/_gGygEKgFfgG4gCHgF9gLcgTsgMrgK4gHBgD7?style=linearGradient&steps=8&angle=180 -->
            <defs>
              <linearGradient id="gradient" x1="0.500" y1="0.000" x2="0.500" y2="1.000">
        <stop offset="0.000" stop-color="#492359" /><stop offset="0.143" stop-color="#922c18" /><stop offset="0.286" stop-color="#cc5000" /><stop offset="0.429" stop-color="#df660a" /><stop offset="0.571" stop-color="#c35544" /><stop offset="0.714" stop-color="#843088" /><stop offset="0.857" stop-color="#3d22b5" /><stop offset="1.000" stop-color="#0a3bb3" />
              </linearGradient>
            </defs>
            <rect x="0" y="0" width="800" height="400" fill="url(#gradient)" />
          </svg>

["#492359", "#922c18", "#cc5000", "#df660a", "#c35544", "#843088", "#3d22b5", "#0a3bb3"]

// https://grabient.com/_gGygEKgFfgG4gCHgF9gLcgTsgMrgK4gHBgD7?style=linearGradient&steps=8&angle=180
// cosine gradient palette — https://iquilezles.org/articles/palettes/
const float STEPS = 8.0;
const float ANGLE = 180.0;

vec3 palette(float t) {
    vec3 a = vec3(0.434, 0.266, 0.351);
    vec3 b = vec3(0.440, 0.135, 0.381);
    vec3 c = vec3(0.732, 1.260, 0.811);
    vec3 d = vec3(0.696, 0.449, 0.251);
    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);
}

[
  [0.434, 0.266, 0.351],
  [0.440, 0.135, 0.381],
  [0.732, 1.260, 0.811],
  [0.696, 0.449, 0.251]
]