Add Dark Mode Support Using prefers-color-scheme

[caneabi]

Add support for light and dark themes using the CSS prefers-color-scheme media query. This will enable the application to automatically adapt to the user's OS or browser theme preference.

The implementation should use CSS variables (--custom-variable-name) to define theme-specific colors and styles. These variables will be scoped under the :root selector for both prefers-color-scheme: light and prefers-color-scheme: dark.

Below is a proof-of-concept (code is bad and i did not impliment every element)

/* Default light theme */
@media (prefers-color-scheme: light){
:root {
  --bg-color: hsl(206, 12%, 95%);
  --text-color: hsl(200, 35%, 25%);
  --color-primary: hsl(207, 90%, 54%);
  --outline-color: hsl(188, 100%, 54%);
  --button-bg: linear-gradient(to right, #e0e0e0, #bdbdbd);
  --button-bg-box-shadow-color: rgba(160, 160, 160, 0.5);
  --button-bg-primary: linear-gradient(to right, hsl(207, 90%, 61%), hsl(218, 100%, 58%));
  --button-bg-primary-box-shadow-color: hsla(207, 90%, 61%, 0.5);
  --button-bg-secondary: linear-gradient(to right, hsl(262, 47%, 55%), hsl(265, 100%, 46%));
  --button-bg-secondary-box-shadow-color: hsla(258, 58%, 42%, 0.5);
  --button-bg-danger: linear-gradient(to right, hsl(0, 84%, 58%), hsl(0, 78%, 50%));
  --button-bg-danger-box-shadow-color: hsla(0, 58%, 42%, 0.5);
  --button-bg-success: linear-gradient(to right, hsl(130, 58%, 45%), hsl(130, 67%, 45%));
  --button-bg-success-box-shadow-color: hsla(128, 80%, 48%, 0.5);
  --button-action-shadow-color: hsla(200, 15%, 60%, 0.12);
  --underline-color: hsl(200, 35%, 65%);
  --secondary-text-color: hsl(200, 14%, 60%);
  --send-icon-hover-color: hsl(262, 52%, 47%);
  --send-spinner-icon-color: hsl(200, 15%, 70%);
  --success-icon-color: hsl(144, 40%, 57%);
  --error-icon-color: hsl(0, 86%, 63%);
  --copy-icon-color: hsl(144, 40%, 57%);
  --copy-icon-bg-color: hsl(144, 100%, 96%);
  --copy-icon-shadow-color: hsla(200, 15%, 60%, 0.12);
  --focus-outline-color: hsla(207, 90%, 61%, 0.5);
  --checkbox-bg-color: hsl(262, 47%, 63%);
  --input-shadow-color: hsla(200, 15%, 70%, 0.2);
  --input-hover-shadow-color: hsla(200, 15%, 70%, 0.4);
  --input-label-color: hsl(200, 35%, 25%);
  --table-bg-color: hsl(200, 12%, 95%);
  --table-shadow-color: hsla(200, 20%, 70%, 0.3);
  --table-tr-border-color: hsl(200, 14%, 94%);
  --table-tr-hover-bg-color: hsl(200, 14%, 98%);
  --table-head-tr-border-color: hsl(200, 14%, 90%);
  --table-status-gray-bg-color: hsl(200, 12%, 95%);
  --keyframe-slidey-offset: 0;
  --stats-bg: #19212d;
  --hr-color: #fff;
  --button-bg-color: #fff;
  --button-bg-hover-color: hsl(217.25, 85.85%, 50%);
  --button-text-color: #000;
}
}
/* Dark theme */
@media (prefers-color-scheme: dark) {
  :root {
    --bg-color: #101827;
    --text-color: #f8fafc;
    --color-primary: hsl(207, 90%, 61%);
    --outline-color: hsl(207, 90%, 54%);
    --button-bg: linear-gradient(to right, #2d3748, #4a5568);
    --button-bg-box-shadow-color: rgba(45, 55, 72, 0.5);
    --button-bg-primary: linear-gradient(to right, hsl(207, 90%, 48%), hsl(218, 90%, 40%));
    --button-bg-primary-box-shadow-color: hsla(207, 90%, 48%, 0.5);
    --button-bg-secondary: linear-gradient(to right, hsl(262, 47%, 45%), hsl(265, 100%, 40%));
    --button-bg-secondary-box-shadow-color: hsla(258, 58%, 32%, 0.5);
    --button-bg-danger: linear-gradient(to right, hsl(0, 84%, 48%), hsl(0, 78%, 40%));
    --button-bg-danger-box-shadow-color: hsla(0, 58%, 32%, 0.5);
    --button-bg-success: linear-gradient(to right, hsl(130, 58%, 35%), hsl(130, 67%, 35%));
    --button-bg-success-box-shadow-color: hsla(128, 80%, 38%, 0.5);
    --button-action-shadow-color: hsla(200, 15%, 30%, 0.12);
    --underline-color: hsl(200, 35%, 40%);
    --secondary-text-color: hsl(200, 14%, 50%);
    --send-icon-hover-color: hsl(262, 52%, 37%);
    --send-spinner-icon-color: hsl(200, 15%, 50%);
    --success-icon-color: hsl(144, 40%, 47%);
    --error-icon-color: hsl(0, 86%, 53%);
    --copy-icon-color: hsl(144, 40%, 47%);
    --copy-icon-bg-color: hsl(144, 100%, 86%);
    --copy-icon-shadow-color: hsla(200, 15%, 30%, 0.12);
    --focus-outline-color: hsla(207, 90%, 48%, 0.5);
    --checkbox-bg-color: hsl(262, 47%, 53%);
    --input-shadow-color: hsla(219.13, 41.82%, 10.78%, 1);
    --input-hover-shadow-color: hsla(200, 15%, 50%, 0.4);
    --input-label-color: #f8fafc;
    --table-bg-color: #1F2937;
    --table-shadow-color: hsla(200, 20%, 40%, 0.3);
    --table-tr-border-color: #374151;
	--table-tr-hover-bg-color: #27303f;
    --table-tr-bg-color: #27303f;
    --table-head-tr-border-color: #2d3748;
    --table-status-gray-bg-color: #1F2937;
	--stats-bg: #19212d;
    --hr-color: hsl(217.25, 85.85%, 58.43%);
    --button-bg-color: hsl(217.25, 85.85%, 58.43%);
    --button-bg-hover-color: hsl(217.25, 85.85%, 50%);
    --button-text-color: #ffffff;
  }
}

table tr {
  flex: 1 1 auto;
  background-color: var(--table-tr-bg-color);
}

.stats-period {
  background-color: var(--stats-bg);
}

/* Horizontal rule (hr) styling */
hr {
  background-color: var(--hr-color);
  border-width: 2px;
}

/* Button styles */
.button, button.nav {
  background-color: var(--button-bg-color);
  color: var(--button-text-color);
  border: none;
  padding: 10px 20px;
  border-radius: 5px;
  cursor: pointer;
  transition: background-color 0.3s ease, color 0.3s ease;
}

a.button, button {
	 color: var(--button-text-color);
}

table .tab a {
	background-color: var(--button-bg-color);
}
@media (prefers-color-scheme: dark) {
table .tab a.active{
background-color: #3366b9;
}

button.nav:disabled {
 background-color: #3366b9;
}
}

/* Button hover effect */
.button:hover {
  background-color: var(--button-bg-hover-color);
}

/* Optional: Focus outline for buttons */
.button:focus {
  outline: 2px solid var(--hr-color);
}

#main-table-wrapper table tbody td.right-fade:after {
visibility: hidden;
}

@media (prefers-color-scheme: dark) {
	input[type="text"], input[type="email"], input[type="password"] {
background-color: color(srgb 0.1499 0.1854 0.2443);
border-bottom: 5px solid #262f3e;
		color: var(--text-color);
	}
}

table {
	background-color: var(--table-bg-color);
}

#main-table-wrapper table button.nav {
  background-color: var(--button-bg-color);
  color: var(--button-text-color);
}

#stats {
	background-color: var(--table-bg-color);
}

#main-table-wrapper table tr.edit {
	background-color: var(--table-bg-color);
}

.dialog .box {
	background-color: var(--bg-color);
}

@media (prefers-color-scheme: dark) {
input[type="text"]:focus, input[type="email"]:focus, input[type="password"]:focus {
	box-shadow: 0 20px 35px hsla(248.08, 90.48%, 11.55%, 0.4);
}
}