.reveal section {
    font-size: 80%;
}
.reveal .qrcode {
    display: inline-block;
}
.reveal .qrcode img {
    margin: 18px 0 0 4px;
}
/* simple message-bubble styles for .session .right and .left */
.reveal .session {
    display: flex;
    flex-direction: column;
    gap: 0.5em;
    margin: 0.6em auto;
    width: 100%;
    max-width: 800px;
    align-items: stretch;
}
.reveal .session .left,
.reveal .session .right {
    display: inline-block;
    max-width: 75%;
    padding: 0.6em 0.9em;
    border-radius: 12px;
    line-height: 1.35;
    word-wrap: break-word;
    box-shadow: 0 1px 3px rgba(0,0,0,0.08);
    font-size: 0.95em;
}
/* left-aligned (assistant/response) */
.reveal .session .left {
    background: #f4f4f6;
    color: #111;
    align-self: flex-start;
    border-bottom-left-radius: 6px;
}
/* right-aligned (student/request) */
.reveal .session .right {
    background: #0b74de;
    color: #fff;
    align-self: flex-end;
    border-bottom-right-radius: 6px;
}

/* typewriter effect for session fragments */
.reveal .session .fragment.fragment-typing {
    color: transparent !important;
}
.reveal .session .fragment.fragment-typing .fragment-char {
    color: transparent;
    transition: color 0.1s linear;
}
.reveal .session .fragment.fragment-typing .fragment-char.is-visible {
    color: var(--fragment-color, inherit);
}

.reveal .icon-transition {
    position: relative;
    width: min(360px, 80vw);
    min-height: 220px;
    margin: 0.75em auto 0;
    display: flex;
    align-items: center;
    justify-content: center;
}
.reveal .icon-transition__image {
    width: 100%;
    height: auto;
    display: block;
    transition: opacity 0.6s ease;
}
.reveal .icon-transition__question {
    position: absolute;
    inset: 0;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: clamp(4rem, 10vw, 6.5rem);
    font-weight: 700;
    color: #6a2bd2;
    text-shadow: 0 8px 26px rgba(0, 0, 0, 0.25);
    pointer-events: none;
}

.reveal a.brand-link {
    position: relative;
    color: #6a2bd2;
    font-weight: 600;
    text-decoration: none;
    animation: brandGlow 3s ease-in-out infinite;
}
.reveal a.brand-link::after {
    content: "";
    position: absolute;
    inset: -10px;
    border-radius: 999px;
    box-shadow: 0 0 30px rgba(106, 43, 210, 0.35), 0 0 55px rgba(106, 43, 210, 0.25);
    opacity: 0;
    transition: opacity 0.3s ease;
    pointer-events: none;
}
.reveal a.brand-link:hover::after,
.reveal a.brand-link:focus-visible::after {
    opacity: 1;
}

@keyframes brandGlow {
    0% { text-shadow: 0 0 12px rgba(106, 43, 210, 0.45), 0 0 28px rgba(106, 43, 210, 0.25); }
    50% { text-shadow: 0 0 28px rgba(106, 43, 210, 0.75), 0 0 55px rgba(106, 43, 210, 0.4); }
    100% { text-shadow: 0 0 12px rgba(106, 43, 210, 0.45), 0 0 28px rgba(106, 43, 210, 0.25); }
}