Gradient palette editor — #d03e3d to #3560ff

/* https://grabient.com/_gJ0gJniqlgHZgGviolgL6gL5gBigMvgJHgHd?style=linearGradient&steps=7&angle=270 */

background: linear-gradient(270deg, #d03e3d 0.000%, #ff8123 16.667%, #ffd626 33.333%, #c8ff45 50.000%, #6bf981 66.667%, #2db3d9 83.333%, #3560ff 100.000%);

<svg xmlns="http://www.w3.org/2000/svg" width="800" height="400" viewBox="0 0 800 400" preserveAspectRatio="none">
            <!-- https://grabient.com/_gJ0gJniqlgHZgGviolgL6gL5gBigMvgJHgHd?style=linearGradient&steps=7&angle=270 -->
            <defs>
              <linearGradient id="gradient" x1="1.000" y1="0.500" x2="0.000" y2="0.500">
        <stop offset="0.000" stop-color="#d03e3d" /><stop offset="0.167" stop-color="#ff8123" /><stop offset="0.333" stop-color="#ffd626" /><stop offset="0.500" stop-color="#c8ff45" /><stop offset="0.667" stop-color="#6bf981" /><stop offset="0.833" stop-color="#2db3d9" /><stop offset="1.000" stop-color="#3560ff" />
              </linearGradient>
            </defs>
            <rect x="0" y="0" width="800" height="400" fill="url(#gradient)" />
          </svg>

["#d03e3d", "#ff8123", "#ffd626", "#c8ff45", "#6bf981", "#2db3d9", "#3560ff"]

// https://grabient.com/_gJ0gJniqlgHZgGviolgL6gL5gBigMvgJHgHd?style=linearGradient&steps=7&angle=270
// cosine gradient palette — https://iquilezles.org/articles/palettes/
const float STEPS = 7.0;
const float ANGLE = 270.0;

vec3 palette(float t) {
    vec3 a = vec3(0.628, 0.615, 10.917);
    vec3 b = vec3(0.473, 0.431, 10.789);
    vec3 c = vec3(0.762, 0.761, 0.098);
    vec3 d = vec3(0.815, 0.583, 0.477);
    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);
}

[
  [0.628, 0.615, 10.917],
  [0.473, 0.431, 10.789],
  [0.762, 0.761, 0.098],
  [0.815, 0.583, 0.477]
]