Dark blue gray to sand to cobalt blue gradient palette editor

/* https://grabient.com/_gHDgFCgFSgHygHOgFVgPbgQigKugGSgErgEp */

background: linear-gradient(90deg, #0b2e3d 0.000%, #00000c 16.667%, #640e00 33.333%, #d88a1f 50.000%, #e9c859 66.667%, #878491 83.333%, #1209ad 100.000%);

<svg xmlns="http://www.w3.org/2000/svg" width="800" height="400" viewBox="0 0 800 400" preserveAspectRatio="none">
            <!-- https://grabient.com/_gHDgFCgFSgHygHOgFVgPbgQigKugGSgErgEp -->
            <defs>
              <linearGradient id="gradient" x1="0.000" y1="0.500" x2="1.000" y2="0.500">
        <stop offset="0.000" stop-color="#0b2e3d" /><stop offset="0.167" stop-color="#00000c" /><stop offset="0.333" stop-color="#640e00" /><stop offset="0.500" stop-color="#d88a1f" /><stop offset="0.667" stop-color="#e9c859" /><stop offset="0.833" stop-color="#878491" /><stop offset="1.000" stop-color="#1209ad" />
              </linearGradient>
            </defs>
            <rect x="0" y="0" width="800" height="400" fill="url(#gradient)" />
          </svg>

["#0b2e3d", "#00000c", "#640e00", "#d88a1f", "#e9c859", "#878491", "#1209ad"]

// https://grabient.com/_gHDgFCgFSgHygHOgFVgPbgQigKugGSgErgEp
// cosine gradient palette — https://iquilezles.org/articles/palettes/
const float STEPS = 7.0;
const float ANGLE = 90.0;

vec3 palette(float t) {
    vec3 a = vec3(0.451, 0.322, 0.338);
    vec3 b = vec3(0.498, 0.462, 0.341);
    vec3 c = vec3(0.987, 1.058, 0.686);
    vec3 d = vec3(0.402, 0.299, 0.297);
    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);
}

[
  [0.451, 0.322, 0.338],
  [0.498, 0.462, 0.341],
  [0.987, 1.058, 0.686],
  [0.402, 0.299, 0.297]
]