style.css

/*
 * Globals
 */

/* Links */
a,
a:focus,
a:hover {
    color: #fff;
}

/* Rounded circle image */
.cirleimage {
    border-radius: 50%;
}

/* Custom default button */
.btn-secondary,
.btn-secondary:hover,
.btn-secondary:focus {
    color: #333;
    text-shadow: none; /* Prevent inheritance from `body` */
    background-color: #fff;
    border: .05rem solid #fff;
}

/*
 * Base structure
 */

html,
body {
    height: 100%;
    background-color: #21446b;
}

body {
    color: #fff;
    text-align: center;
    text-shadow: 0 .05rem .1rem rgba(0, 0, 0, .5);
}

/* Extra markup and styles for table-esque vertical and horizontal centering */
.site-wrapper {
    display: table;
    width: 100%;
    height: 100%; /* For at least Firefox */
    min-height: 100%;
    -webkit-box-shadow: inset 0 0 5rem rgba(0, 0, 0, .5);
    box-shadow: inset 0 0 5rem rgba(0, 0, 0, .5);
}

.site-wrapper-inner {
    display: table-cell;
    vertical-align: top;
}

.cover-container {
    margin-right: auto;
    margin-left: auto;
}

/* Padding for spacing */
.inner {
    padding: 2rem;
}

/*
 * Header
 */

.masthead {
    margin-bottom: 2rem;
}

.masthead-brand {
    margin-bottom: 0;
}

.nav-masthead .nav-link {
    padding: .25rem 0;
    font-weight: bold;
    color: rgba(255, 255, 255, .5);
    background-color: transparent;
    border-bottom: .25rem solid transparent;
}

.nav-masthead .nav-link:hover,
.nav-masthead .nav-link:focus {
    border-bottom-color: rgba(255, 255, 255, .25);
}

.nav-masthead .nav-link + .nav-link {
    margin-left: 1rem;
}

.nav-masthead .active {
    color: #fff;
    border-bottom-color: #fff;
}

@media (min-width: 48em) {
    .masthead-brand {
        float: left;
    }

    .nav-masthead {
        float: right;
    }
}

/*
 * Cover
 */

.cover {
    padding: 0 1.5rem;
}

.cover .btn-lg {
    padding: .75rem 1.25rem;
    font-weight: bold;
}

/*
 * Footer
 */

.mastfoot {
    color: rgba(255, 255, 255, .5);
}

/*
 * Affix and center
 */

@media (min-width: 40em) {
    /* Pull out the header and footer */
    .masthead {
        position: fixed;
        top: 0;
    }

    .mastfoot {
        position: fixed;
        bottom: 0;
    }

    /* Start the vertical centering */
    .site-wrapper-inner {
        vertical-align: middle;
    }

    /* Handle the widths */
    .masthead,
    .mastfoot,
    .cover-container {
        width: 100%; /* Must be percentage or pixels for horizontal alignment */
    }
}

@media (min-width: 62em) {
    .masthead,
    .mastfoot,
    .cover-container {
        width: 42rem;
    }
}