html,
body {
    height: 100%;
    margin: 0;
    padding: 0;
}

/* APP LAYOUT */
.app-wrapper {
    min-height: 100vh;
    display: flex;
    flex-direction: column;
}

/* MAIN CONTENT AREA */
.app-content {
    flex: 1;
    /* center content */
    display: flex;
    justify-content: center;
    align-items: center;
    /* keep bootstrap container width */
    width: 100%;
    /* prevent navbar overlap */
    padding-top: 90px;
    padding-bottom: 20px;
}

/* FOOTER STAYS BOTTOM */
footer {
    margin-top: auto;
}

/* BIG SCREENS */
@media (min-width: 992px) {
    .app-content {
        min-height: calc(100vh - 170px);
    }
}

/* MOBILE/TABLET */
@media (max-width: 991px) {
    .app-content {
        min-height: calc(100vh - 150px);
    }
}

/* CENTER WRAPPER ONLY */
#exeview {
    width: 100%;
    display: flex;
    justify-content: center;
}

.icon-btn {
    width: 46px;
    height: 46px;
    border: none;
    border-radius: 12px;
    background: #fff;
    color: #4facfe;
    display: flex;
    align-items: center;
    justify-content: center;
    box-shadow: 0 3px 10px rgba(0,0,0,0.1);
    cursor: pointer;
    transition: 0.2s ease;
    outline: none;
}