:root{
    --background: linear-gradient(45deg, rgba(0,255,255,1) 0%, rgba(255,255,255,1) 50%, rgba(255,0,255,1) 100%);
    --background-color: #f5f5f5;
    --text-color: #333;
    --header-footer-background-color: rgb(0,0,0,.25);
    --header-footer-text-color: #fff;
    --input-background-color: #fff;
    --container-background-color: #dfdfdf;
    --tab-active-background-color: #efefef;
    --tab-inactive-background-color: #c5c5c5;
    --button-background-color: #007bff;
    --button-background: linear-gradient(45deg, rgba(0,255,255,.5) 0%, rgba(255,255,255,.5) 50%, rgba(255,0,255,.5) 100%);
    --button-hover-background-color: #0069d9;
    --button-hover-background: linear-gradient(45deg, rgba(0,255,255,1) 0%, rgba(255,255,255,1) 50%, rgba(255,0,255,1) 100%);
    --button-active-background-color: #0051a8;
    --button-active-background: linear-gradient(45deg, rgba(0,255,255,.25) 0%, rgba(255,255,255,1) 50%, rgba(255,0,255,.25) 100%);
    --button-text-color: var(--text-color);
    --border: .1rem solid #c5c5c5;
    --border-radius: 0.25rem;
    --shadow: 0 0 1rem rgba(0, 0, 0, 0.1);
}

* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

body {
    font-family: sans-serif;
    background: var(--background-color);
    background: var(--background);
    background-position: top left;
    background-size: 100vw 100vh;
    background-attachment: fixed;
    color: var(--text-color);
    display: grid;
    grid-template-rows: min-content 1fr min-content;
    height: 100vh;
    position: relative;
}

header {
    background: var(--header-footer-background-color);
    color: var(--header-footer-text-color);
    text-align: center;
    display: flex;
    flex-direction: row;
    justify-content: center;
    align-content: center;
    align-items: center;
    gap: 1rem;
    height: 6rem;
}

.logo {
    width: 4rem;
    vertical-align: middle;
    opacity: .75;
}

h1 {
    font-size: 2rem;
}

main {
    width: 90vw;
    max-width: 40rem;
    margin: 2rem auto;
    background: var(--container-background-color);
    padding: 2rem;
    border-radius: var(--border-radius);
    box-shadow: var(--shadow);
}

section {
    margin-bottom: 1rem;
}

form {
    display: flex;
    flex-direction: column;
}

label {
    margin-bottom: .5rem;
    font-weight: bold;
}

input, textarea {
    margin-top: .5rem;
    padding: 1rem;
    color: var(--text-color);
    border: var(--border);
    border-radius: var(--border-radius);
    background-color: var(--input-background-color);
    font-size: 1.25rem;
}

button, input[type="submit"] {
    background: var(--button-background-color);
    background: var(--button-background);
    color: var(--button-text-color);
    border: var(--border);
    border-radius: var(--border-radius);
    margin-top: .5rem;
    padding: 1rem;
    font-size: 1rem;
    font-weight: bold;
    cursor: pointer;
}

button:hover, input[type="submit"]:hover {
    background: var(--button-hover-background-color);
    background: var(--button-hover-background);
}

button:active, input[type="submit"]:active {
    background: var(--button-active-background-color);
    background: var(--button-active-background);
}

button svg {
    fill: currentColor;
}

input:disabled {
    opacity: .5;
}

dialog {
    width: 90vw;
    max-width: 45rem;
    margin: 2rem auto;
    background: var(--container-background-color);
    color: var(--text-color);
    padding: 20px;
    border: 1px solid var(--secondary-color);
    border-radius: var(--border-radius);
    box-shadow: var(--shadow);
    margin: 50vh auto 0;
    transform: translatey(-50%);
}

dialog::backdrop {
    background: rgba(128, 128, 128, 0.5);
}

p {
    margin: 1rem;
}

hr {
    margin: 1rem 0;
}

a {
    color: var(--text-color);
    text-decoration: none;
}

a:hover {
    text-decoration: underline;
}

a:active {
    color: var(--button-active-background-color);
}

#spinner-dialog {
    text-align: center;
    margin-top: 0;
    transform: translatey(0);
}

#spinner-dialog[open] {
    animation-name: show-spinner;
    animation-duration: .5s;
    animation-fill-mode: forwards;
}

#spinner-dialog.hide {
    animation-name: hide-spinner;
    animation-duration: .5s;
    animation-fill-mode: forwards;
}

@keyframes show-spinner {
    from {transform: translatey(-100%);}
    to {transform: translatey(0);}
}

@keyframes hide-spinner {
    from {transform: translatey(0);}
    to {transform: translatey(-100%);}
}

footer {
    width: 100%;
    padding: 1rem 0;
    background: var(--header-footer-background-color);
    color: var(--header-footer-text-color);
    text-align: center;
}

menu.tabs {
    margin: 2rem 0 0;
}
menu.tabs ul {
    display: flex;
    list-style: none;
    margin-bottom: 1rem;
}

menu.tabs ul li {
    margin-right: 1rem;
}

menu.tabs ul li a {
    padding: 1rem;
    border: var(--border);
    border-radius: var(--border-radius) var(--border-radius) 0 0;
    text-decoration: none;
    color: var(--text-color);
    border-bottom: 0;
    background-color: var(--tab-inactive-background-color);
}

menu.tabs ul li a.active {
    background: var(--tab-active-background-color);
    font-weight: bold;
}

menu.tabs ul li a:hover {
    background: var(--tab-active-background-color); 
}

menu.tabs ul li a.active:hover {
    background: var(--tab-active-background-color);
}

.tab-content {
    display: none;
    margin-top: -.1rem;
    border: var(--border);
    border-radius: 0 var(--border-radius) var(--border-radius) var(--border-radius);
    padding: 2rem;
}

.tab-content.active {
    display: block;
    background-color: var(--tab-active-background-color);
}

@media (prefers-color-scheme: dark) {

    :root {
        --background: linear-gradient(45deg, rgba(0,255,255,1) 0%, rgba(0,0,0,1) 50%, rgba(255,0,255,1) 100%);
        --background-color: #333;
        --text-color: #f5f5f5;
        --header-footer-text-color: #fff;
        --input-background-color: #444;
        --container-background-color: #444;
        --tab-active-background-color: #555;
        --tab-inactive-background-color: #666;
        --button-background-color: #014288;
        --button-background: linear-gradient(45deg, rgba(0,255,255,.5) 0%, rgba(0,0,0,.5) 50%, rgba(255,0,255,.5) 100%);
        --button-hover-background-color:#0069d9;
        --button-hover-background: linear-gradient(45deg, rgba(0,255,255,1) 0%, rgba(0,0,0,1) 50%, rgba(255,0,255,1) 100%);
        --button-active-background-color: #0051a8;
        --button-active-background: linear-gradient(45deg, rgba(0,255,255,.25) 0%, rgba(0,0,0,1) 50%, rgba(255,0,255,.25) 100%);
        --button-text-color: #fff;
        --border: .1rem solid #666;
        --border-radius: 0.25rem;
        --shadow: 0 0 1rem rgba(0, 0, 0, 0.1);
    }
}