/* ----- FLOATING BUTTON (theme switch) based on float-btn style ----- */
.float-theme-btn {
    position: fixed;
    bottom: 2rem;
    right: 2rem;
    width: 3.75rem;
    height: 3.75rem;
    border-radius: 9999px;
    background-color: var(--float-bg);
    border: 1px solid var(--float-border);
    box-shadow: 0 10px 25px -5px var(--shadow-color);
    display: flex;
    align-items: center;
    justify-content: center;
    cursor: pointer;
    transition: all 0.25s cubic-bezier(0.2, 0.9, 0.3, 1.1);
    z-index: 9999;
    backdrop-filter: blur(8px);
    /* start visible — different from back-to-top, always there */
    opacity: 1;
    visibility: visible;
}

.float-theme-btn:hover {
    background-color: var(--accent-gold);
    border-color: var(--accent-gold);
    transform: translateY(-6px) scale(1.03);
    box-shadow: 0 20px 28px -10px rgba(198,167,94,0.4);
}

/* icon styling */
.float-theme-btn svg {
    width: 1.8rem;
    height: 1.8rem;
    stroke: var(--float-icon);
    stroke-width: 2;
    fill: none;
    stroke-linecap: round;
    stroke-linejoin: round;
    transition: all 0.2s;
}

.float-theme-btn:hover svg {
    stroke: #ffffff;  /* white on hover */
    transform: rotate(15deg) scale(1.05);
}

/* tooltip (same style as back-to-top) */
.float-tooltip {
    position: absolute;
    right: 4.5rem;
    background: #1e293b;
    color: white;
    font-size: 0.7rem;
    font-weight: 500;
    padding: 0.3rem 0.8rem;
    border-radius: 2rem;
    white-space: nowrap;
    opacity: 0;
    pointer-events: none;
    transition: opacity 0.15s;
    box-shadow: 0 4px 12px rgba(0,0,0,0.15);
}

.float-theme-btn:hover .float-tooltip {
    opacity: 1;
}