/* https://grabient.com/_gYcgIXe87ga2gFihRqgBogbQgBngIlgIYgO1?style=linearGradient&steps=7&angle=135 */

background: linear-gradient(135deg, #0030aa 0.000%, #00b2d0 16.667%, #14cbe7 33.333%, #2e3dee 50.000%, #4c6ce6 66.667%, #6ee2ce 83.333%, #9478a7 100.000%);

<svg xmlns="http://www.w3.org/2000/svg" width="800" height="400" viewBox="0 0 800 400" preserveAspectRatio="none">
            <!-- https://grabient.com/_gYcgIXe87ga2gFihRqgBogbQgBngIlgIYgO1?style=linearGradient&steps=7&angle=135 -->
            <defs>
              <linearGradient id="gradient" x1="0.146" y1="0.146" x2="0.854" y2="0.854">
        <stop offset="0.000" stop-color="#0030aa" /><stop offset="0.167" stop-color="#00b2d0" /><stop offset="0.333" stop-color="#14cbe7" /><stop offset="0.500" stop-color="#2e3dee" /><stop offset="0.667" stop-color="#4c6ce6" /><stop offset="0.833" stop-color="#6ee2ce" /><stop offset="1.000" stop-color="#9478a7" />
              </linearGradient>
            </defs>
            <rect x="0" y="0" width="800" height="400" fill="url(#gradient)" />
          </svg>

["#0030aa", "#00b2d0", "#14cbe7", "#2e3dee", "#4c6ce6", "#6ee2ce", "#9478a7"]

// https://grabient.com/_gYcgIXe87ga2gFihRqgBogbQgBngIlgIYgO1?style=linearGradient&steps=7&angle=135
// cosine gradient palette — https://iquilezles.org/articles/palettes/
const float STEPS = 7.0;
const float ANGLE = 135.0;

vec3 palette(float t) {
    vec3 a = vec3(1.564, 0.535, -4.293);
    vec3 b = vec3(1.718, 0.354, 5.226);
    vec3 c = vec3(0.104, 1.744, 0.103);
    vec3 d = vec3(0.549, 0.536, 0.949);
    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);
}

[
  [1.564, 0.535, -4.293],
  [1.718, 0.354, 5.226],
  [0.104, 1.744, 0.103],
  [0.549, 0.536, 0.949]
]

Gradient palette editor — #0030aa to #9478a7