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

html, body {
    width: 100%;
    height: 100%;
    background: #000;
    overflow: hidden;
    font-family: 'Helvetica Neue', Arial, sans-serif;
}

#caption-canvas {
    width: 100vw;
    height: 100vh;
    display: block;
    background: #000;
    object-fit: contain;
}

.overlay {
    position: fixed;
    inset: 0;
    display: flex;
    align-items: center;
    justify-content: center;
    background: rgba(0, 0, 0, 0.65);
    z-index: 10;
}

.overlay-card {
    background: #0f172a;
    color: #f8fafc;
    padding: 32px;
    border-radius: 16px;
    width: min(420px, 90vw);
    box-shadow: 0 20px 40px rgba(0, 0, 0, 0.4);
    text-align: center;
}

.overlay-card h1 {
    font-size: 1.6rem;
    margin-bottom: 12px;
}

.overlay-card p {
    font-size: 0.95rem;
    margin-bottom: 20px;
    color: rgba(248, 250, 252, 0.8);
}

.overlay-card input {
    width: 100%;
    padding: 12px;
    border-radius: 10px;
    border: 1px solid rgba(148, 163, 184, 0.5);
    background: #0b1220;
    color: #f8fafc;
    font-size: 1rem;
    margin-bottom: 16px;
}

.overlay-card .btn {
    width: 100%;
    padding: 12px;
    border-radius: 10px;
    border: none;
    background: #22c55e;
    color: #0f172a;
    font-weight: 700;
    font-size: 1rem;
    cursor: pointer;
}

.overlay-card .btn:hover {
    background: #16a34a;
}

.hidden {
    display: none;
}