:root {
    /* CSS Custom Properties for easy theming */
    --ttcgpt-bg-color: #f8fafc;
    --ttcgpt-hover-color: #ffffff;
    --ttcgpt-text-color: #0f172a;
    --ttcgpt-button-size: 48px;
    --ttcgpt-right-offset: 20px;
    --ttcgpt-border-radius: 24px;
    --ttcgpt-z-index: 99999;
}

@keyframes ttcgpt-premium-glow {
    0% { box-shadow: 0 4px 15px rgba(0, 0, 0, 0.1), 0 0 10px rgba(255, 255, 255, 0.1); }
    50% { box-shadow: 0 8px 25px rgba(0, 0, 0, 0.2), 0 0 25px rgba(255, 255, 255, 0.4); }
    100% { box-shadow: 0 4px 15px rgba(0, 0, 0, 0.1), 0 0 10px rgba(255, 255, 255, 0.1); }
}

.ttcgpt-floating-button {
    position: fixed;
    top: calc(50% - 100px);
    right: var(--ttcgpt-right-offset);
    transform: translateY(-50%);
    z-index: var(--ttcgpt-z-index);
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 8px;
    background-color: var(--ttcgpt-bg-color);
    color: var(--ttcgpt-text-color);
    border: 1px solid rgba(255, 255, 255, 0.5);
    border-radius: var(--ttcgpt-border-radius);
    height: var(--ttcgpt-button-size);
    padding: 0 20px;
    cursor: pointer;
    transition: transform 0.2s ease, background-color 0.2s ease;
    text-decoration: none;
    pointer-events: auto;
    animation: ttcgpt-premium-glow 3s infinite ease-in-out;
}

.ttcgpt-floating-button:hover,
.ttcgpt-floating-button:focus {
    background-color: var(--ttcgpt-hover-color);
    transform: translateY(calc(-50% - 3px)) scale(1.02);
    outline: none;
}

.ttcgpt-floating-button:active {
    transform: translateY(-50%) scale(0.98);
}

.ttcgpt-icon {
    flex-shrink: 0;
    width: 20px;
    height: 20px;
}

.ttcgpt-label {
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
    font-size: 15px;
    font-weight: 500;
    line-height: 1;
}

/* Mobile: Collapse to compact circular icon-only button */
@media (max-width: 768px) {
    .ttcgpt-floating-button {
        width: var(--ttcgpt-button-size);
        padding: 0;
        border-radius: 50%;
        gap: 0;
    }
    .ttcgpt-label {
        display: none;
    }
}