:root {
    --primary-color: #337ab7;
    --success-color: darkgreen;
    --warn-color: darkorange;
    --danger-color: red;
    --info-color: #5bc0de;
    --primary-font: system-ui;
    --secondary-font: sans-serif;
    --card-bg-color: #F5F5F5;
    --black-025: hsl(210, 8%, 97.5%);
    --black-050: hsl(210, 8%, 95%);
    --black-075: hsl(210, 8%, 90%);
    --black-100: hsl(210, 8%, 85%);
    --black-150: hsl(210, 8%, 80%);
    --black-200: hsl(210, 8%, 75%);
    --black-300: hsl(210, 8%, 65%);
    --black-350: hsl(210, 8%, 60%);
    --black-400: hsl(210, 8%, 55%);
    --black-500: hsl(210, 8%, 45%);
    --black-600: hsl(210, 8%, 35%);
    --black-700: hsl(210, 8%, 25%);
    --black-750: hsl(210, 8%, 20%);
    --black-800: hsl(210, 8%, 15%);
    --black-900: hsl(210, 8%, 5%);
}

html {
    font-family: var(--primary-font);
}

.main {
    justify-content: space-between;
    margin: 0 24px;
    gap: 24px;
}

p,
h1,
h2,
h3,
h4,
h5 {
    font-family: var(--secondary-font);
}

.label {
    padding: 2px 4px;
    border-radius: 4px;
}

.label.label-info {
    background-color: var(--info-color);
}

@keyframes spinner {
    to {
        transform: rotate(360deg);
    }
}

.spinner:after {
    content: '';
    box-sizing: border-box;
    position: relative;
    display: inline-flex;
    width: 12px;
    height: 12px;
    border-radius: 50%;
    border-top: 2px solid #07d;
    border-right: 2px solid transparent;
    animation: spinner .6s linear infinite;
}

.fx {
    display: flex;
    flex-wrap: wrap;
}

.card {
    background-color: var(--card-bg-color);
    border: 1px solid lightgrey;
    padding: 12px;
    width: 300px;
    opacity: 0.3;
    border-radius: 4px;
}

.card.activated {
    opacity: 1;
}

.card.fastest {
    outline: 2px solid green;
    outline-offset: -2px;
    position: relative;
}

.card.fastest::after {
    content: '✓';
    position: absolute;
    top: 8px;
    right: 8px;
    width: 32px;
    height: 32px;
    background-color: green;
    color: white;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 20px;
    font-weight: bold;
    box-shadow: 0 2px 4px rgba(0, 0, 0, 0.2);
    z-index: 10;
}

.card .card-header {
    line-height: 1.2em;
    font-size: 0.9em;
    height: 30px;
    overflow: hidden;
    font-family: monospace;
}

.card .card-title {
    line-height: 1.2em;
    font-size: 1.2em;
    font-weight: 600;
    border-bottom: 1px solid #BDBDBD;
}

.server-uris.card-body .server-uri {
    margin-bottom: 12px;
    background-color: white;
    padding: 4px;
    border-radius: 4px;
}

.server-uris.card-body .server-uri .uri {
    font-size: 12px;
}

.server-uris.card-body .server-uri .speed {
    font-size: 12px;
}

.success {
    color: var(--success-color);
}

.failure {
    color: var(--danger-color);
}

.text-muted {
    color: var(--black-600);
}

.text-center {
    text-align: center;
}

.btn {
    border: 1px solid var(--primary-color);
    color: var(--primary-color);
    height: 16px;
    padding: 0 8px;
    border-radius: 4px;
    margin-left: 4px;
    font-size: 12px;
    background-color: transparent;
    cursor: pointer;
    transition: all 0.2s ease-in-out;
    box-shadow: 0 1px 3px rgba(51, 122, 183, 0.1);
    font-weight: 500;
    text-decoration: none;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    min-width: 20px;
}

.btn:hover {
    background-color: var(--primary-color);
    color: #fff;
    transform: translateY(-1px);
    box-shadow: 0 3px 6px rgba(51, 122, 183, 0.3);
}

.btn:active {
    transform: translateY(0);
    box-shadow: 0 1px 3px rgba(51, 122, 183, 0.2);
}

.btn.disabled,
.btn[disabled],
fieldset[disabled] .action-btn {
    cursor: not-allowed;
    filter: alpha(opacity=65);
    opacity: .65;
    box-shadow: none;
}

.hidden {
    display: none;
}

.alert-danger {
    border: 1px solid var(--danger-color);
    background-color: lightsalmon;
}

.alert-info {
    background-color: var(--info-color);
}

.server-heading-info {
    font-size: 32px;
    display: flex;
    flex-direction: column;
    gap: 2px;
    align-items: center;
    justify-content: center;
}