/* Button */
.btn {
    width: 100%;
    padding: .75rem 1rem;
    background: var(--accent);
    color: #000;
    font-weight: 700;
    font-size: 1rem;
    border: none;
    border-radius: var(--radius);
    cursor: pointer;
    transition: opacity .15s;
    display: flex;
    align-items: center;
    justify-content: center;
    gap: .4rem;
}

.btn:hover { opacity: .75; }
.btn:disabled { opacity: .4; cursor: not-allowed; }

.btn--ghost {
    background: var(--surface-2);
    border: 1px solid var(--border);
    color: var(--text);
}

/* Full-width bar under a card that opens a secondary panel, such as the progress
   breakdown or an event's measurement details. Also styles a <summary>. */
.panel-toggle {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: .5rem;
    width: 100%;
    background: var(--surface);
    border: 1px solid var(--border);
    border-radius: 8px;
    padding: .6rem;
    color: var(--text);
    font-size: .85rem;
    font-weight: 600;
    cursor: pointer;
    list-style: none;
    transition: border-color .15s;
}

.panel-toggle::-webkit-details-marker {
    display: none;
}

.panel-toggle:hover {
    border-color: var(--text-muted);
}