Rainbow dark teal to deep sea blue to purplish gray to drab gradient palette editor

/* https://grabient.com/_doogD5gF5ihFgGcgBqgBmgBogOhgOXgLsgJK */

background: linear-gradient(90deg, #003e49 0.000%, #004a5f 16.667%, #2d5576 33.333%, #70607a 50.000%, #966b68 66.667%, #9e754f 83.333%, #887e45 100.000%);

<svg xmlns="http://www.w3.org/2000/svg" width="800" height="400" viewBox="0 0 800 400" preserveAspectRatio="none">
            <!-- https://grabient.com/_doogD5gF5ihFgGcgBqgBmgBogOhgOXgLsgJK -->
            <defs>
              <linearGradient id="gradient" x1="0.000" y1="0.500" x2="1.000" y2="0.500">
        <stop offset="0.000" stop-color="#003e49" /><stop offset="0.167" stop-color="#004a5f" /><stop offset="0.333" stop-color="#2d5576" /><stop offset="0.500" stop-color="#70607a" /><stop offset="0.667" stop-color="#966b68" /><stop offset="0.833" stop-color="#9e754f" /><stop offset="1.000" stop-color="#887e45" />
              </linearGradient>
            </defs>
            <rect x="0" y="0" width="800" height="400" fill="url(#gradient)" />
          </svg>

["#003e49", "#004a5f", "#2d5576", "#70607a", "#966b68", "#9e754f", "#887e45"]

// https://grabient.com/_doogD5gF5ihFgGcgBqgBmgBogOhgOXgLsgJK
// 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(-9.688, 0.249, 0.377);
    vec3 b = vec3(10.309, 0.412, 0.106);
    vec3 c = vec3(0.102, 0.104, 0.929);
    vec3 d = vec3(0.919, 0.748, 0.586);
    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);
}

[
  [-9.688, 0.249, 0.377],
  [10.309, 0.412, 0.106],
  [0.102, 0.104, 0.929],
  [0.919, 0.748, 0.586]
]