Dark dusky purple to marine gradient palette editor

/* https://grabient.com/_gDUgDXgEagEsgCogDygFjgGlgFRgBKgOUgNS?style=linearGradient&steps=4&angle=0 */

background: linear-gradient(0deg, #7a5c6c 0.000%, #515f84 33.333%, #1a457f 66.667%, #002160 100.000%);

<svg xmlns="http://www.w3.org/2000/svg" width="800" height="400" viewBox="0 0 800 400" preserveAspectRatio="none">
            <!-- https://grabient.com/_gDUgDXgEagEsgCogDygFjgGlgFRgBKgOUgNS?style=linearGradient&steps=4&angle=0 -->
            <defs>
              <linearGradient id="gradient" x1="0.500" y1="1.000" x2="0.500" y2="0.000">
        <stop offset="0.000" stop-color="#7a5c6c" /><stop offset="0.333" stop-color="#515f84" /><stop offset="0.667" stop-color="#1a457f" /><stop offset="1.000" stop-color="#002160" />
              </linearGradient>
            </defs>
            <rect x="0" y="0" width="800" height="400" fill="url(#gradient)" />
          </svg>

["#7a5c6c", "#515f84", "#1a457f", "#002160"]

// https://grabient.com/_gDUgDXgEagEsgCogDygFjgGlgFRgBKgOUgNS?style=linearGradient&steps=4&angle=0
// cosine gradient palette — https://iquilezles.org/articles/palettes/
const float STEPS = 4.0;
const float ANGLE = 0.0;

vec3 palette(float t) {
    vec3 a = vec3(0.212, 0.215, 0.282);
    vec3 b = vec3(0.300, 0.168, 0.242);
    vec3 c = vec3(0.355, 0.421, 0.337);
    vec3 d = vec3(0.074, 0.916, 0.850);
    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);
}

[
  [0.212, 0.215, 0.282],
  [0.300, 0.168, 0.242],
  [0.355, 0.421, 0.337],
  [0.074, 0.916, 0.850]
]