/* Buttons */
.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 8px;
    padding: 10px 24px;
    border: none;
    border-radius: var(--radius-md);
    font-size: var(--font-size-base);
    font-weight: 500;
    cursor: pointer;
    transition: background var(--transition-fast), opacity var(--transition-fast);
    outline: none;
}

.btn:disabled {
    opacity: 0.5;
    cursor: not-allowed;
}

.btn-primary {
    background: var(--color-primary);
    color: #fff;
}

.btn-primary:hover:not(:disabled) {
    background: var(--color-primary-dark);
}

.btn-secondary {
    background: var(--color-bg);
    color: var(--color-text);
}

.btn-secondary:hover:not(:disabled) {
    background: var(--color-border);
}

.btn-danger {
    background: var(--color-danger);
    color: #fff;
}

.btn-icon {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    width: 40px;
    height: 40px;
    border: none;
    border-radius: var(--radius-full);
    background: transparent;
    color: var(--color-text-secondary);
    cursor: pointer;
    transition: background var(--transition-fast);
}

.btn-icon:hover {
    background: var(--color-hover);
}

.btn-icon svg {
    width: 24px;
    height: 24px;
}

/* Inputs */
.input-group {
    display: flex;
    flex-direction: column;
    gap: 6px;
}

.input-group label {
    font-size: var(--font-size-sm);
    color: var(--color-text-secondary);
    font-weight: 500;
}

.input {
    width: 100%;
    padding: 10px 14px;
    border: 1px solid var(--color-border);
    border-radius: var(--radius-md);
    font-size: var(--font-size-base);
    color: var(--color-text);
    background: var(--color-surface);
    outline: none;
    transition: border-color var(--transition-fast);
}

.input:focus {
    border-color: var(--color-primary-light);
}

.input-search {
    background: var(--color-bg);
    border: none;
    border-radius: var(--radius-md);
    padding: 8px 12px 8px 36px;
}

/* Avatar */
.avatar {
    width: var(--avatar-size);
    height: var(--avatar-size);
    border-radius: var(--radius-full);
    background: var(--color-primary-light);
    color: #fff;
    display: flex;
    align-items: center;
    justify-content: center;
    font-weight: 600;
    font-size: var(--font-size-lg);
    flex-shrink: 0;
    overflow: hidden;
    text-transform: uppercase;
}

.avatar img {
    width: 100%;
    height: 100%;
    object-fit: cover;
}

.avatar-sm {
    width: var(--avatar-size-sm);
    height: var(--avatar-size-sm);
    font-size: var(--font-size-sm);
}

.avatar-lg {
    width: var(--avatar-size-lg);
    height: var(--avatar-size-lg);
    font-size: var(--font-size-xl);
}

/* Presence dot */
.presence-dot {
    width: 10px;
    height: 10px;
    border-radius: var(--radius-full);
    border: 2px solid var(--color-surface);
    position: absolute;
    bottom: 0;
    right: 0;
}

.presence-dot.online { background: var(--color-online); }
.presence-dot.offline { background: var(--color-offline); }

/* Badge */
.badge {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    min-width: 20px;
    height: 20px;
    padding: 0 6px;
    border-radius: 10px;
    background: var(--color-secondary);
    color: #fff;
    font-size: var(--font-size-xs);
    font-weight: 600;
}

/* Modal */
.modal-overlay {
    position: fixed;
    inset: 0;
    background: rgba(0,0,0,0.5);
    display: flex;
    align-items: center;
    justify-content: center;
    z-index: var(--z-modal);
    padding: 20px;
}

.modal {
    background: var(--color-surface);
    border-radius: var(--radius-lg);
    width: 100%;
    max-width: 440px;
    max-height: 80vh;
    overflow: hidden;
    display: flex;
    flex-direction: column;
    box-shadow: var(--shadow-lg);
}

.modal-header {
    display: flex;
    align-items: center;
    gap: 16px;
    padding: 16px 20px;
    background: var(--color-primary);
    color: #fff;
}

.modal-header h3 {
    flex: 1;
    font-size: var(--font-size-lg);
    font-weight: 500;
}

.modal-body {
    padding: 20px;
    overflow-y: auto;
    flex: 1;
}

.modal-footer {
    padding: 12px 20px;
    display: flex;
    justify-content: flex-end;
    gap: 8px;
    border-top: 1px solid var(--color-border);
}

/* Toast */
.toast {
    position: fixed;
    bottom: 20px;
    left: 50%;
    transform: translateX(-50%);
    background: var(--color-text);
    color: #fff;
    padding: 10px 20px;
    border-radius: var(--radius-md);
    font-size: var(--font-size-sm);
    z-index: var(--z-toast);
    animation: toastIn 0.3s ease, toastOut 0.3s ease 2.7s;
}

@keyframes toastIn {
    from { opacity: 0; transform: translateX(-50%) translateY(20px); }
    to { opacity: 1; transform: translateX(-50%) translateY(0); }
}

@keyframes toastOut {
    from { opacity: 1; }
    to { opacity: 0; }
}

/* Spinner */
.spinner {
    width: 24px;
    height: 24px;
    border: 3px solid var(--color-border);
    border-top-color: var(--color-primary);
    border-radius: var(--radius-full);
    animation: spin 0.6s linear infinite;
}

@keyframes spin {
    to { transform: rotate(360deg); }
}

/* Empty state */
.empty-state {
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    height: 100%;
    gap: 12px;
    color: var(--color-text-secondary);
    padding: 40px;
    text-align: center;
}

.empty-state-icon {
    color: var(--color-border);
}

.empty-state h2 {
    font-size: var(--font-size-xl);
    color: var(--color-text);
    font-weight: 500;
}

.empty-state p {
    font-size: var(--font-size-base);
}

/* Dropdown / Context menu */
.context-menu {
    position: fixed;
    background: var(--color-surface);
    border-radius: var(--radius-md);
    box-shadow: var(--shadow-lg);
    min-width: 180px;
    padding: 6px 0;
    z-index: var(--z-modal);
}

.context-menu-item {
    display: flex;
    align-items: center;
    gap: 12px;
    padding: 10px 20px;
    cursor: pointer;
    font-size: var(--font-size-base);
    color: var(--color-text);
    transition: background var(--transition-fast);
}

.context-menu-item:hover {
    background: var(--color-hover);
}

.context-menu-item.danger {
    color: var(--color-danger);
}

/* FAB (Floating Action Button) */
.fab {
    position: absolute;
    bottom: 20px;
    right: 20px;
    width: 56px;
    height: 56px;
    border-radius: var(--radius-full);
    background: var(--color-secondary);
    color: #fff;
    border: none;
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    box-shadow: var(--shadow-md);
    transition: background var(--transition-fast);
}

.fab:hover {
    background: #20c15e;
}

.fab svg {
    width: 24px;
    height: 24px;
}