/* https://grabient.com/_gKZgj5gCjgJ-giGgAxgCGgBggLzgJ9gHzgFY?style=linearGradient&steps=6&angle=315 */

background: linear-gradient(315deg, #401d23 0.000%, #56211d 20.000%, #6e2d22 40.000%, #88402d 60.000%, #a45b35 80.000%, #bf7e34 100.000%);

<svg xmlns="http://www.w3.org/2000/svg" width="800" height="400" viewBox="0 0 800 400" preserveAspectRatio="none">
            <!-- https://grabient.com/_gKZgj5gCjgJ-giGgAxgCGgBggLzgJ9gHzgFY?style=linearGradient&steps=6&angle=315 -->
            <defs>
              <linearGradient id="gradient" x1="0.854" y1="0.854" x2="0.146" y2="0.146">
        <stop offset="0.000" stop-color="#401d23" /><stop offset="0.200" stop-color="#56211d" /><stop offset="0.400" stop-color="#6e2d22" /><stop offset="0.600" stop-color="#88402d" /><stop offset="0.800" stop-color="#a45b35" /><stop offset="1.000" stop-color="#bf7e34" />
              </linearGradient>
            </defs>
            <rect x="0" y="0" width="800" height="400" fill="url(#gradient)" />
          </svg>

["#401d23", "#56211d", "#6e2d22", "#88402d", "#a45b35", "#bf7e34"]

// https://grabient.com/_gKZgj5gCjgJ-giGgAxgCGgBggLzgJ9gHzgFY?style=linearGradient&steps=6&angle=315
// cosine gradient palette — https://iquilezles.org/articles/palettes/
const float STEPS = 6.0;
const float ANGLE = 315.0;

vec3 palette(float t) {
    vec3 a = vec3(0.665, 2.297, 0.163);
    vec3 b = vec3(0.638, 2.182, 0.049);
    vec3 c = vec3(0.134, 0.096, 0.755);
    vec3 d = vec3(0.637, 0.499, 0.344);
    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);
}

[
  [0.665, 2.297, 0.163],
  [0.638, 2.182, 0.049],
  [0.134, 0.096, 0.755],
  [0.637, 0.499, 0.344]
]

Gradient palette editor — #401d23 to #bf7e34