.form-group {
    display: flex;
    flex-direction: column;
    gap: var(--space-1);
}

.form-label {
    font-size: var(--font-size-sm);
    font-weight: var(--font-weight-medium);
    color: var(--color-text);
}

.form-input {
    padding: var(--space-2) var(--space-3);
    background: var(--color-surface-raised);
    border: 1px solid var(--color-border);
    border-radius: var(--radius-md);
    font-size: var(--font-size-base);
    color: var(--color-text);
    transition: border-color var(--transition-fast), box-shadow var(--transition-fast);
    inline-size: 100%;
}

.form-input::placeholder {
    color: var(--color-text-tertiary);
}

.form-input:focus {
    outline: none;
    border-color: var(--color-border-focus);
    box-shadow: 0 0 0 3px var(--color-accent-bg);
}

.form-input--error {
    border-color: var(--color-error);
}

.form-input--error:focus {
    box-shadow: 0 0 0 3px var(--color-error-bg);
}

.form-error {
    font-size: var(--font-size-xs);
    color: var(--color-error);
}

.form-checkbox {
    display: flex;
    align-items: center;
    gap: var(--space-2);
    font-size: var(--font-size-sm);
    cursor: pointer;
}

.form-checkbox input[type="checkbox"] {
    inline-size: 16px;
    block-size: 16px;
    accent-color: var(--color-accent);
    cursor: pointer;
}

.form-password-wrapper {
    position: relative;
}

.form-password-toggle {
    position: absolute;
    inset-block-start: 50%;
    inset-inline-end: var(--space-3);
    transform: translateY(-50%);
    color: var(--color-text-tertiary);
    cursor: pointer;
    padding: var(--space-1);
}

.form-password-toggle:hover {
    color: var(--color-text-secondary);
}

/* --- Buttons --- */

.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: var(--space-2);
    padding: var(--space-2) var(--space-5);
    font-size: var(--font-size-base);
    font-weight: var(--font-weight-medium);
    border-radius: var(--radius-md);
    transition: background var(--transition-fast), color var(--transition-fast), opacity var(--transition-fast);
    cursor: pointer;
    border: none;
    min-block-size: 44px;
}

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

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

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

.btn--primary:active:not(:disabled) {
    background: var(--color-accent-active);
}

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

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

.btn--full {
    inline-size: 100%;
}

.btn__spinner {
    inline-size: 16px;
    block-size: 16px;
    border: 2px solid rgba(255, 255, 255, 0.3);
    border-block-start-color: #fff;
    border-radius: 50%;
    animation: btn-spin 0.6s linear infinite;
}

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